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JULY 2019
Xplore Space A WORLD SPACE CLUB PUBLICATION
Apollo 50 Special Edition. It's finally landed... the World Space Club Apollo 50 collectors magazine. Packed with awesome mission profiles & behind the scenes exclusives.
Free! 'We came in peace for all mankind'
Features Table of contents 1. Features 2. Letter from the editor 3. Project Mercury - America's first astronauts 5. Project Gemini - Rendezvous... in space! 6. The journey to Apollo - Learning from tragedy 7. Apollo 7 - Around the world in 90 minutes 9. Apollo 8 - From the Earth to the Moon 10. Apollo 8 - Christmas Eve transmission 11. Apollo 9 - Flight of the Spider 12. Apollo 9 - In their own words... 13. Apollo 10 - "Tell the world we have arrived" 24. Apollo 10 - In their own words... 15. Apollo 11 - We chose to go to the Moon 16. Apollo 11 - Meet the astronauts 17. Apollo 11 - Chance favours the prepared 18. Apollo 11 - Mission control 19. Apollo 11 - Countdown to launch 20. Apollo 11 - Dawn at the Cape 21. Apollo 11 - Mission highlights from Apollo 11 25. Apollo 11 - In their own words... 27. Apollo 11 - From Apollo to Earth 28. Apollo 11 - Space rocks 29. Apollo 12 - Lightning, science, and art 32. From reality to imagination - Alan Bean 33. Apollo 13 - "Houston, we've had a problem" 36. Apollo 14 - A golf course like no other 37. Apollo 15 - To drive across another world 38. Apollo 16 - The Lunar Grand Prix 39. Apollo 17 - The last Apollo mission 40. The end of Apollo - Dawn of the post-pioneering age 41. The future - Dawn of the expansion age 42. Journey to the Moon - Three page graphic story 45. The mighty Saturn V - In their own words... 46. Meet the most powerful rocket ever built 47. Apollo CSM/LEM 48. CSM?LEM Diagrams (By Clarence @aerospace_guy) 49. Space suit - The A7L 50. A new generation of space suit technology 51. Have you joined World Space Club yet? 52. Xplore Space Vol. 2
By Clarence, @aerospace_guy Š World Space Club
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Xplore Space World Space Club Magazine
Letter from the editor: Welcome to the first ever edition of Xplore Space Magazine! Well, we really couldn't have picked a more exciting and historic month to launch! When I was set the challenge of producing a special technical edition Apollo 50 magazine for World Space Club, I had no idea quite what I was taking on. This was my first venture into writing and editing a magazine, and it has certainly been a steep learning curve! Perhaps the hardest challenge was not deciding what to put in this edition, but what to leave out. Thanks to NASA's incredible stock of free resources, there is far too much interesting content to share about this historic mission to fit into any one magazine.
The other hard challenge was how to pitch the articles to best please our members. World Space Club is run by young people who are passionate about space, for young people who are passionate about space. However we're all interested in different aspects and disciplines of space, and we're all at different stages in our learning. I'm a 14-year-old future engineer and mission planner and I suspect you will guess that as you read most of the articles! For future magazines, we would love to receive contributions from other World Space Club members, reflecting a variety of space interests, backgrounds, and styles. Please visit worldspaceclub.com if you would like to get involved with, and contribute to the magazine in the future. Finally, I'd like to wish you a great Apollo 50, and I hope you enjoy reading this magazine, and reliving this extraordinary moment in human history through some of the great images and resources that NASA has shared with us all. - Clarence Editor at Xplore Space Magazine, World Space Club You can find me on Twitter at @aerospace_guy
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Project Mercury America's first astronauts
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Our voyage to the Moon started long before Apollo 11 left the launch pad. Even before Kennedy gave that famous speech, NASA had conducted a test flight of a spacecraft called Mercury, that put Alan Shepard into space as America's first astronaut. Later, a slightly modified version of Mercury, paired with a bigger rocket, would make John Glenn the first American to orbit the Earth. But to get to the Moon, we By Clarence, @aerospace_guy Š World Space Club would need to do more than just reach orbit...
Originally known as Project Astronaut, the Mercury program was America's way of putting humans in space during the very early 1960s. An evolution of the US Air Force's Man In Space Soonest program, it was created in October 1958, 6 days after the formation of NASA, and consisted of 20 uncrewed flights, and 6 crewed ones. The Mercury spacecraft was a fairly simple one person capsule, cone shaped with a heat shield on the blunt end, and recovery and space navigational instruments attached to its top. To control its orientation, it was equipped with several tiny rocket motors, called Reaction Control System (RCS) thrusters. Affixed to the base of it was a small retro rocket to de-orbit the spacecraft. To get into space, Mercury capsules were launched atop one of two types of rocket. The first, the Redstone, was basically just a modified ballistic missile from WWII. This rocket could place the capsule in space, but only on a short hop out of the atmosphere lasting a few dosen minutes. The second rocket NASA used was a type of Intercontinental Ballistic Missile (ICBM) called Atlas. The Atlas rocket was designed to lob nuclear warheads across the planet, but it could also be used for more peaceful purposes, specifically, it had the capability to place a Mercury capsule into Earth orbit. Once in Earth orbit, the capsule and its occupant would stay in space for days, before firing the retro-motor and returning to Earth.
At first 17 uncrewed test flights of the spacecraft were performed. Six of these were using a rocket called Little Joe, which only ever flew without an astronaut aboard, and didn't reach space. The Mercury capsule had a small rocket motor atop it to pull it away from an exploding launch vehicle, and in order to test this system, Little Joe rockets were used to fire the unmanned Mercury capsule up to altitude, and the Launch Escape System (LES) was then activated. The other 11 uncrewed tests were made up of 4 atop Redstone boosters, 3 of which were successful. And the rest were atop Atlas rockets. Then, on the 18th mission, astronaut and test pilot Alan Shepard became the first American in space on the 6th of May, 1961, riding atop MercuryRedstone (MR) 3. Followed by MR 4, another suborbital flight, this time with Gus Grissom inside. The next three missions were uncrewed, and then there was Mercury-Atlas 6, 7, 8, and 9, carrying John Glen, Scott Carpenter, Wally Schirra, and Gordon Cooper into orbit. In 1963, the program was cancelled, and NASA's attention turned to their next projects, Gemini and Apollo.
By Clarence, @aerospace_guy Š World Space Club
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Project Gemini Rendezvous... in space!
Compared to Mercury, Gemini was a more capable spacecraft, similar to Mercury in many ways, but able to carry two people, and able to rendezvous and dock with other spacecraft. There were 12 Gemini missions, 8 of which were crewed. Most notably, Gemini 8 was the first to dock with another spacecraft, a (uncrewed) modified Agena upper stage. The mission almost resulted in disaster when a thruster got stuck on, but commander Neil Armstrong and pilot David Scott's quick thinking and extraordinary skills saved the mission. Also notable were the earlier Gemini 6 and 7 missions, which met up in orbit (but did not dock), becoming the first rendezvous between two crewed spacecraft. The first crewed Gemini mission, Gemini 4, was also the first mission to support a spacewalk by an American, Ed White. By the time the age of Apollo came around, Gemini had proven most of the capabilities that would be needed on a Lunar mission. Some people even suggested using a modified Gemini to fly to the Moon, but Apollo easily won out.
Top left: Buzz Aldrin on Gemini 12 Top right: The launch of Gemini 4 Middle right: Gemini 7 as seen from Gemini 6 Bottom right: John F Kennedy tours
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By Clarence, @aerospace_guy Š World Space Club
The journey to Apollo Learning From Tragedy
"Yes, Apollo 1 did cause three deaths, but I believe it saved more than three later" - Michael Collins, CSM Pilot, Apollo 11 The Apollo 11 crew left a medallion on the Lunar surface honoring their friends on Apollo 1. Development for Apollo was going well. The Command Module and Service Module, the main components of the Apollo spacecraft, had been proven in ground based testing, and had even flown to space on short uncrewed hops above the atmosphere, riding atop Apollo 1 mission patch Saturn I rockets, the predecessor to the Saturn V rocket that would launch Apollo to the Moon. NASA considered the Apollo spacecraft ready for crewed flight, and so the Apollo 1 mission was drawn up, to place a crewed Apollo Command and Service Module into Low Earth Orbit (LEO). However, on January the 27th, 1967, a flash fire in the Apollo 1 Command Module during a ground test caused a complete transformation in the approach to the Apollo program. A faulty electrical system in the Command Module, paired with the high oxygen environment, made even the aluminum burn. Three brave astronauts, Gus Grissom, Ed White, and Roger Chaffy, could not be saved once the fire had started, and shock swept through NASA. It could have been a tragedy that destroyed the Apollo program, but everyone at NASA was united in not allowing their friends and colleagues to have died in vain. Instead, hard lessons were learnt, The launch of Apollo 4 and extensive redesigns, and a new reinforced determination to succeed powered the Apollo program forward to eventual success. Following the fire the Apollo Command Module was completely redesigned. The Block I version was scrapped in favor of the Block II, and the electrical systems were completely rebuilt. The old hatch had an overcomplicated latching system, and opened inwards. After Apollo 1 capsule hatches were never designed like that again. The most important thing the investigation had found however, was that a 100% pure oxygen environment can make even aluminum burn. NASA immediately changed the atmospheric composition and pressure inside the spacecraft, switching to a mix of Nitrogen and Oxygen. The mission schedule was also redesigned. Apollos 2 and 3, seeing as they were dependent on Apollo 1, were removed from the The Launch of Apollo 5 flight plan, and instead, a much more cautious approach was taken. Apollo 4 was the first uncrewed test of the Saturn V rocket, and Apollo 5 was the first uncrewed test of the Lunar Excursion Module (LEM), the spacecraft that would journey with the Command and Service Modules to the Moon, and make the journey to the Moon's surface and back. Apollo 4 went mostly smoothly, but there were some problems, that meant NASA would need to do another uncrewed test of the Saturn V before it would be rated for crewed flight. Apollo 5 launched on a smaller rocket, the Saturn IB, a derivative of the Saturn I mentioned previously. The LEM performed well enough to be man-rated without another uncrewed test, but the descent stage did show some problems. Apollo 6 was the second uncrewed test of the Saturn V. It did not go well. The rocket almost shock itself apart, and barely got to The launch of Apollo 6 orbit. Nevertheless, the information learned was enough to not have to do a third uncrewed test. By Clarence, @aerospace_guy Š World Space Club
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Apollo 7 Around the world in 90 minutes
On a bright clear morning on the 11 of October 1968, after the traditional astronauts breakfast of steak and eggs, at Space Launch Complex 34, Cape Kennedy, three astronauts climbed into their Apollo 7 Command Module and blasted off into the sky atop a pillar of orange flames. The crewed Apollo program had just taken off. 7
By Clarence, @aerospace_guy Š World Space Club
The goal of the mission was to demonstrate the Apollo Command Service Module (CSM)’s performance with crew aboard. The CSM had been flown uncrewed before, but there was always a chance something might fail on an actual mission, and so an all up test of the CSM in Low Earth Orbit (LEO) was needed. For the mission, test pilots Commander Walter Schirra, Command Module Pilot Donn Eisele and Lunar Module Pilot R. Walter Cunningham were selected. They were going to be the first to fly the Apollo spacecraft, and to prepare them they had spent over 600 hours in the simulator with over 725 manual controls, practicing for almost every conceivable situation they could find themselves in. For this mission a Saturn IB rocket was chosen, because its larger sister the Saturn V was still in testing, and even if it wasn’t, a Saturn V would be unnecessary for simply sending a CSM into LEO. The Saturn IB rocket performed excellently, and two and a half minutes after liftoff the first stage was jettisoned, and the second stage was fired. This was the first time astronauts had flown on a spacecraft propelled by liquid hydrogen. Ten and a half minutes after liftoff the S-IVB second stage stage shutdown and the first Apollo crew had reached orbit. Once in orbit, the CSM separated from the now almost empty S-IVB rocket stage, and Schirra fired the CSM's Reaction Control System (RCS) thrusters to pull 15 meters ahead of the S-IVB. The small amount of unused fuel in the S-IVB was now vented. This was essential to make sure the S-IVB was safe to use as a test target for rendezvous manoeuvres. For this to work, the hydrogen and oxygen in the S-IVB were vented separately to insure they wouldn't ignite. By the next day, the two had drifted over 130 kilometres apart. To practice rendezvousing with another spacecraft, the CSM fired its RCS jets to manoeuvre back towards the S-IVB.
There was just one problem though: the crew couldn't find it! To reduce the mass of the CSM, docking radar hadn't been installed and the astronauts were expected to find it by optical instruments and the computer. As it turned out however, the computer on the Apollo 7 spacecraft didn’t work like it did in the simulator. Instead of tracking the rendezvous target during the four minutes it took to make a calculation, it gave up. Sometimes the computer would calculate the position of a landmark on Earth and declare that it was 1000 meters underwater. This meant that until the computer was fixed, the crew had to rely on star charts, and the sextant, being backed up by simply looking out the window. After spending a while searching, the CSM finally found the S-IVB and approached within 21 meters. Cunningham reported the panels on the S-IVB’s that would house the Lunar Excursion Module (LEM) had not fully deployed. This mishap would could have been a cause of concern on a mission that had carried a LEM (Apollo 7 didn’t however, so for this mission it was fine), and the panels would be completely jettisoned on future missions. After the rendezvous simulations, it was time to test the Service Propulsion System (SPS) engine. This was a crucial system on a Lunar mission, if It didn’t ignite the astronauts would be stranded. On Apollo 7, the engine was fired 8 times, working almost perfectly. The Apollo CSM performed excellently. It operated for 10.8 days, which was longer than a journey to the Moon. With a few exceptions, the other systems in the spacecraft operated well. There were a few issues with the fuel cells, the windows were a bit foggy, the reentry battery chargers underperformed, and the cooling fans were too loud, but nothing of importance failed. That wasn’t to say the flight was easy however, in order to get as much done as possible the crew were working almost every single second for the first two days of the mission. "In orbit, our time line was rather condensed for the first two days; we were much too busy, in a sense, for a first flight. But our intent was to achieve as many objectives as we could so that, if anything went wrong and we had to come down, we could still move ahead to a lunar mission without having to repeat this flight." - Schirra, after the mission was over. After deorbiting, the Command Module separated from the Service Module, and reentered the Earths atmosphere. After spending 10 days in space, to everyones relief, the main parachutes deployed correctly, and the Command Module splashed down in the Atlantic southeast of Bermuda, less than 2 kilometres from the planned landing location. At first, when the Command Module splashed down it flipped over, but flotation bags affixed to its top inflated and turned it upright again. Apollo 7 was a complete success, the CSM was qualified for more missions, and it had paved the way for NASA’s next flight - around the Moon. By Clarence, @aerospace_guy © World Space Club
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Apollo 8 From the Earth to the Moon
Some people stay at home for Christmas, some people visit friends, some people go on holiday. In 1968, Frank Borman, James Lovell Jr. and William Anders spent Christmas on a working vacation around the Moon… and the whole world went with them. Apollo 8 was the first ever crewed Saturn V launch, and the first ever crewed circumlunar flight, a momentous moment in space history. However, it wasn’t always meant to be that way. Initially Apollo 8 was only intended to go into Low Earth Orbit (LEO), in order to conduct a crewed test of the spacecraft that would eventually land on the Moon, the Lunar Excursion Module (LEM), and the orbital mothership, the Command Service Module (CSM). However, the LEM was not ready. NASA, on a tight schedule, could have flown Apollo 8 in LEO without the LEM, essentially repeating Apollo 7, however that would have underutilized the potential of the mighty Saturn V. So instead, the Apollo team made a bold decision, and decided to launch the CSM without a LEM, but not merely into Earth Orbit, but instead all the way into Lunar. This change in plan transformed the mission into (at that time) the most extraordinary voyage in history. This would be the first time humans would fly around the Moon.
Key mission events: The launch was flawless, and two hours and fifty minutes later, for the first time in the program, Apollo 8 CAPCOM Michael Collins said “[Apollo 8] you are go for TLI” (Trans-Lunar injection, the manoeuvre used to send the spacecraft into a Lunar transfer orbit). The S-IVB third stage then re-ignited, and Apollo 8 was thrusted towards the Moon. Half an hour later, the CSM separated from the spent S-IVB third stage, and fired its reaction control system (RCS) thrusters to move away from the S-IVB, so that when it vented its remaining propellent it wouldn’t risk hitting the CSM. On their way to the Moon two midcourse correction burns were performed to test the Service Propulsion System (SPS) engine, which later would be used to enter and then break Lunar orbit. It was critical that the engine worked, and luckily, it did. As they started to round the Moon, the astronauts saw a sight nobody had ever seen before: the far side of the Moon. A few hours later they passed behind the Moon entirely and lost the signal back to Earth.
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By Clarence, @aerospace_guy © World Space Club
The first Lunar Orbit Insertion (LOI) burn, to place the CSM in Lunar orbit, took place at 69 hours, 8 minutes, 52 seconds after launch, lasted four minutes, and reduced the spacecraft's staggering 2.5 kilometres per second velocity by 0.9 kilometres per second, placing Apollo 8 in a 110 by 310 kilometre orbit around the Moon. At this point astronauts Frank Borman, James Lovell Jr. and William Anders became the first humans to orbit another celestial body. Later a second small burn was performed to circularise the orbit at 110 kilometres. While they were in Lunar orbit for 20 hours, the three astronauts worked constantly to photograph and map as much of the Lunar surface as possible in preparation for future landing missions. Additionally, six live telecasts were performed during the flight, two during translunar coast, two during Lunar orbit and two during transEarth coast. The telecasts were broadcast live to everywhere on Earth, and in Lunar orbit on Christmas Eve the crew read verses from the first chapter of Genesis, and wished viewers, "Good night, good luck, a Merry Christmas and God bless all of you, all of you on the good Earth.” "We came all this way to explore the moon, and the most important thing is that we discovered the Earth" The quality of the broadcasts was exceptional, many have said that after all the problems and terrible events on Earth that year, that short but wonderful broadcast from space to Earth “saved 1968”. While they were in Lunar orbit, the crew also took one of the most iconic photographs in history, showing not the Sun rising as were all used to seeing on Earth, but the spectacular beauty of our Earth rising over the Lunar horizon. 89 hours after launch, after their 10th Lunar orbit, the SPS engine ignited again to propel the CSM back to Earth. During the coast to Earth there were three planned mid-course corrections, however only one ended up being needed. 146 hours after launch the the Service Module was jettisoned, and the Command Module entered Earths atmosphere at terrifying 11 kilometres per second, faster than any crewed reentry before it, with temperatures on the heat shield reaching 3000 Kelvin (2730 Celsius). Luckily, the heat shield held, mission control breathed again, and the capsule splashed down in the Pacific at 10:51 am, 5 kilometres from the recovery ship USS Yorktown, 147 hours after launch. All of the objectives and goals were achieved. The Saturn V launch vehicle performed perfectly. The whole world celebrated with NASA; Apollo 8 had proven that humans could fly to the Moon. By Clarence, @aerospace_guy © World Space Club William Anders We are now approaching lunar sunrise, and for all the people back on Earth, the crew of Apollo 8 has a message that we would like to send to you. In the beginning God created the heaven and the earth. And the earth was without form, and void; and darkness was upon the face of the deep. And the Spirit of God moved upon the face of the waters. And God said, Let there be light: and there was light. And God saw the light, that it was good: and God divided the light from the darkness. James Lovell And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day. And God said, Let there be a firmament in the midst of the waters, and let it divide the waters from the waters. And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament: and it was so. And God called the firmament Heaven. And the evening and the morning were the second day. Frank Borman And God said, Let the waters under the heaven be gathered together unto one place, and let the dry land appear: and it was so. And God called the dry land Earth; and the gathering together of the waters called the Seas: and God saw that it was good.
And from the crew of Apollo 8, we close with good night, good luck, a Merry Christmas – and God bless all of you, all of you on the good Earth.
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Apollo 9 Flight of the Spider
With the success of Apollo 8, NASA was well on track to make the Moon landings. It would be hard however, they only had one year left to do it, but then they had never thought it would be easy! By February 1969 the Lunar Excursion Module (LEM) was finally ready for crewed flight, and on the 3rd of March, 1969, Apollo 9 blasted of from Cape Kennedy, and into Low Earth Orbit (LEO). The launch went well, and was similar to Apollo 8’s flight just over 3 months prior. Aboard were Commander James McDivitt, Command Module Pilot David Scott and Lunar Module Pilot Russell Schweickart. Apollo 9’s mission was to test out the, now ready, LEM in LEO in order to prove it was worthy of crewed flights to the Moon. Everything went according to plan. Once the S-IVB third stage burned out, and the Apollo stack reached orbit, the Command Service Module (CSM) separated from the SIVB, rotated 180 degrees, and docked to the LEM that had been stored inside its fairing during launch. The LEM then separated from the S-IVB, and the LEM and CSM used their reaction control system (RCS) thrusters to pull away from the spent S-IVB rocket stage. The CSM then briefly fired its Service Propulsion System (SPS) engine, both to stabilise its orbit, and to prove that the engine could be fired while the CSM and LEM were docked together without causing any damage. 3 days in, McDivitt and Schweickart put on spacesuits and traveled through the tunnel connecting the two spacecraft to the LEM to perform a systems checkout. The LEM’s descent engine was also fired, to prove that it worked. On day 4, Schweickart performed a half hour long EVA (spacewalk) testing the EVA mobility unit, including the portable life support system backpack. On day 5, a groundbreaking step was taken in spaceflight history when McDivitt and Schweickart boarded the LEM, and it then separated from the CSM. This was the first time astronauts had ever flown on a spacecraft not capable of returning to Earth, since the LEM had no heat shield or parachutes. If they failed to re-dock with the CSM they would not be able to return to Earth. Another example of the extraordinary bravery of all the pioneering Apollo (and earlier) astronauts, and cosmonauts.
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By Clarence, @aerospace_guy © World Space Club
The LEM’s descent engine was fired for 25 seconds, in order to circularise the LEM’s orbit. Four hours later the LEM descent stage was jettisoned for ignition of the ascent stage engine. This manoeuvre was all the more hair-raising because the ascent engine couldn’t be tested on the ground, and the first time it fired would be in space. Luckily the engine fired perfectly, and 6 hours later the CSM and LEM redocked to each other, McDivitt and Schweickart transferred to the CSM, and the LEM was jettisoned. Two telecasts were made to Earth from Apollo 9. The first, on March 5, lasted for almost seven minutes, while the second telecast on the following day lasted about 13 minutes. The crew also took multi-spectral terrain photos of the Earth. On the tenth day of the mission, after several firings of the SPS, the Apollo 9 CSM deorbited and the capsule safely splashed down in the Pacific, 241 hours after launch. NASA had successfully completed another invaluable step towards its goal - the Moon.
In their own words... Apollo 9 astronauts Rusty Schweickart, David Scott, and James McDivitt reflect upon their mission.
- Rusty Schweickart: “We were the first crew that was going to get a chance to fly this vehicle, and test this vehicle, that was going to take humans to the moon. We were very aware of the time pressure, and everything has to go right, if for sure we were going to meet Kennedy’s goal, getting to the Moon in that decade and back. Apollo 9 was an engineering mission, from beginning to end. We tested every possible thing that could be tested. The mission was completely dedicated to testing the systems, the engines, and guidance and navigation, all kinds of things that we could do in Earth orbit. “ - James McDivitt: “So when we first got into orbit we had a lot of stuff to do, and so we needed to make sure we had all the data we could get. The Lunar Module had to land on the Moon, I mean thats what it was designed for, and then it had to get back up to the Command Module so there was a ride home. “ - David Scott: “Its really very difficult to get the coordinate systems in you’re head, normally we dock looking out this way [points forwards], and for the docking with the Lunar module, you had to look up this way [points upwards], so the control systems didn’t operate they way it normally would. “ “It was the most complicated and messy system of springs and levers and latches, and unbelievably complex. “ - James McDivitt: “We depressurized both the Lunar Module and the Command Module and Rusty was going to get out and transfer over to the Command Module and we were doing that to see that it could be done..“ - Rusty Schweickart: “And partway up the front of the Lunar Module, making sure I could safely do that and not poke holes in the suit with the antennas and things, and everything was quiet, nobody was talking, that beautiful Earth out there, I mean that's where I really saw just the beauty of where I was. “ - James McDivitt: “Dave wanted to get out of the spacecraft too. Part of the mission was for him to open up the hatch, so we were all out there in a vacuum. “ - Rusty Schweickart: “Here we are at this historic moment, that we're all part off, not just the astronauts but everyone that's alive today, and we're all on this small planet of representatives of life, we're beginning to move out from this planet, which as far as we know contains all the life in our little corner of the universe. “ <the testing was successfully completed in Earth orbit> “And then it just worked beautifully, it was an amazing vehicle. “ - David Scott: “And it was a hell of a ride!”
By Clarence, @aerospace_guy © World Space Club
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Apollo 10 "Tell the world we have arrived" After the success that was Apollo 9, it looked like NASA was all ready for an actual landing mission. However, one more flight would have to take place first - an all up dress rehearsal of the landing in Low Lunar Orbit (LLO). This would be critical if the next mission - Apollo 11 - was to be successful. Apollo 10 lifted off from the Cape atop its Saturn V booster just like 8 and 9 had before it. Aboard were Commander Thomas Stafford, Command Module Pilot John Young and Lunar Module Pilot Eugene Cernan. After one and a half orbits, the S-IVB third stage re-ignited and Apollo 10 was sent onto a trajectory around the Moon, for the first time since Apollo 8. Twenty-five minutes later, the Command Service Module (CSM) separated for transposition and docking with the Lunar Excursion Module (LEM), similar to the manoeuvre that Apollo 9 had performed in Earth orbit. Three hours after launch the crew did a live TV transmission back to Earth, showing the docking process and the interior of the Command Module. An hour later, about four hours after launch, Apollo 10 separated from the S-IVB stage, which was followed by another 3 live telecasts. The launch had been very successful, and only one of four planned mid-course corrections were needed. Seventy-six hours into the flight, the spacecraft performed Lunar orbit insertion (LOI), firing the Service Propulsion System (SPS) engine, and a second SPS burn 4.5 hours later circularized the orbit at 150 kilometres. Stafford and Cernan crawled into the LEM, named Snoopy after one of the safety mascots, and 100 hours into the mission, undocked from the CSM. After briefly flying side by side with the CSM, the LEM ignited its descent motor, and in order to simulate the later Apollo 11 landing mission, began descending to the Lunar surface. The LEM flew over landing site 2 in the Sea of Tranquility. The landing radar was tested, providing both "high gate" and "low gate" data. The descent engine was then fired twice for 40 seconds, placing the LEM into a 30 by 500 kilometre orbit, so the LEM and its crew were just a mere 30 kilometres from the surface at the lowest point in their orbit. Take a moment to compare that to the 380,000 kilometres distance that the Moon is from Earth, and you can begin to imagine the excitement and awe that generated around the world in 1968. On the 14th orbit around the Moon, the descent stage of the LEM was detached, and the ascent stage engine ignited. So far all had been going well, but then suddenly a crisis occurred.
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By Clarence, @aerospace_guy Š World Space Club
The LEM started tumbling uncontrollably, threatening to crash into the Lunar surface. Not just the mission, but also the astronauts lives were in immanent danger. Luckily, under extreme pressure Cernan was able to wrestle back control of the tumbling craft, and saved the mission. According to Cernan the LEM tumbled end-over end eight times, and had it continued for even a few more seconds it would have been unrecoverable, and they would have crashed. This was the closest an Apollo mission would come to disaster until Apollo 13. The cause was a switch in the LEMâ&#x20AC;&#x2122;s cockpit set in the wrong position, which confused the guidance computer, taking the LEM out of abort mode. With the crisis averted, the LEM then rendezvoused with the CSM, using its reaction control system (RCS) thrusters to close in and dock, 106 hours into the flight. After Stafford and Cernan crawled back into the CSM, the LEM was jettisoned, and the rest of the time in Lunar orbit was spent photographing and mapping the surface. On the 31st orbit, the SPS engine was lit, and the CSM was thrown onto a course back to Earth. Only one mid-course correction was needed during the return. After the Command and Service modules separated, the Apollo 10 Command Module reentered the Earths atmosphere on the 26th of May, at the highest velocity of any crewed spacecraft, going over Mach 36 (0.0037% the speed of light), and splashed down in the Pacific. It's landing was within visual range of its primary recovery ship, the USS Princeton. Apollo 10 completed a flight of 192 hours, three minutes, 23 seconds, one minute, 24 seconds longer than planned. All of the goals of the mission had been achieved. Other than the brief crisis in the LEM, the mission was fully successful, and everything but the actual Moon landing itself had been practiced. The dress rehearsal was over...
In their own words...
“They give a silver snoopy excellence award, I wanted to honour the people that worked so hard, so we called it Snoopy. Well, you needed two names, so naturally the other one was Charlie Brown.
Apollo 10 astronaut Thomas Stafford reflects upon the mission that paved the way for Apollo 11. We are grateful to NASA for this interview.
You’re amazed by what you see [on the Moon]. The one thing that always amazed me were the size of the boulders. There were these gigantic craters, and down in the bottom, and up on the rim would be boulders. We were using Hasselblad cameras, the highest resolution available then, and radar was going. So radar map, photo map, and visual map. We’re coming down, going upside down and backwards to retrograde, I heard the thrusters start to fire. I heard this big bang, bang, bang. So, what I did, the staging switch was here [points with hand], I raised the thing, and boom! Stage it. And meanwhile, I went to hard stops. But I got it back under control, and we made the manoeuvre, came back, and did a perfect rendezvous. One thing people always ask ‘Were you frightened, were you scared?’ The answer is no. We were fighter pilots, test pilots, so we knew what risks were, you did everything you could to mitigate the risk, but there was a risk. We understood that. We had a series of debriefings with them [the Apollo 11 crew], because we had all the procedures worked out. In fact, I remember I went to Neil, I say ‘Buddy, here you are.’ ‘Heres all the techniques, all the procedures, down to the last 50,000 feet, and you take it from there!’ Powered descent, 50,000 feet up, its all done. So he just followed all the procedures we had.” - Thomas Stafford
By Clarence, @aerospace_guy © World Space Club
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Apollo 11 We choose to go to the Moon
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By Clarence, @aerospace_guy Š World Space Club
Meet The Astronauts Chosen... To Boldly Go Where No Man Has Gone Before Edwin 'Buzz' Aldrin Jr
Neil Armstrong
Michael Collins
Buzz Aldrin was born on January 20, 1930, in Montclair, New Jersey. His father, a colonel in the U.S. Air Force, encouraged his interest in flight.
Neil Armstrong was born in Wapakoneta, Ohio, on August 5, 1930. By age 22 he had flown 78 combat missions in the Korean War, he then finished college, & became an exceptional test pilot.
1930 was obviously a very good vintage for astronauts, as Michael Collins was also born on October 31, 1930 (in Rome, Italy). He became a fighter pilot, distinguished test pilot, & inspired by John Glenn, he was selected by NASA to be part of the third group of astronauts.
Aldrin became a fighter pilot & flew in the Korean War. In 1963 he was selected by NASA for the Gemini 12 mission. The first astronaut with a PHD, he was known as 'Doctor Rendezvous'. He was chosen as LEM pilot for Apollo 11. “I know the sky is not the limit, because there are footprints on the Moon—& I made some of them! So don’t allow anyone to denigrate or inhibit your lofty aspirations. Your dream can take you much higher and much farther than anyone ever thought possible! I know mine did.” Since Apollo, Buzz has become known not only as the Moon Man, but also the Mars Guy. He is working tirelessly to inspire a new generation to pick up the baton & not just get back to the Moon, but go onwards to Mars. He has also worked on developing a new type of spacecraft & trajectory to get to Mars, the Aldrin Cycler.
He later joined NACA, the organization that would become NASA, during which he flew X-15 rocketplanes. He joined the astronaut program in 1962 & was commander for his first mission, Gemini 8, in 1966. He was also spacecraft commander for Apollo 11. "It suddenly struck me that that tiny pea, pretty & blue, was the Earth. I put up my thumb and shut one eye, & my thumb blotted out the planet Earth. I didn't feel like a giant. I felt very, very small." "I just see it as a beginning, not just this flight but this program, which has really just been a very short piece of human history, an instant in history, the entire program is a beginning of a new age."
"By refocusing our space program on Mars for America's future, we can restore the sense of wonder & adventure in space exploration that we knew in the summer of 1969. We won the Moon race; now it's time for us to live & work on Mars, first on its moons & then on its surface."
Following Apollo, Neil returned to his passion of aeronautics, teaching at the University of Cincinnati, but after his years years as a fighter pilot, test pilot & Lunar pilot, he preferred upon retirement to fly gliders as he felt they gave him new challenges.
Buzz has an insatiable appetite for adventure & exploration. He's been to the bottom of the ocean to visit the Titanic, & explored both the North & South poles. His favorite thing to do on this planet is scuba diving, which is the closest feeling to being in space.
"Gliders, sail planes, they're wonderful flying machines. It's the closest you can come to being a bird."
His first spaceflight was the Gemini 10 mission, where he performed a spacewalk. He was the CSM pilot for Apollo 11. He was Capcom, the mission controller who communicated with astronauts in space, for Apollo 8. "We have taken to the Moon the wealth of this nation, the vision of its political leaders, the intelligence of its scientists, the dedication of its engineers, the careful craftsmanship of its workers, & the enthusiastic support of its people. We have brought back rocks, & I think it is a fair trade... Man has always gone where he has been able to go. It’s that simple. He will continue pushing back his frontier, no matter how far it may carry him from his homeland." "Well Apollo was designed to be a three man job, and the third which I perform is I think as important, no more so, no less so than the two positions. I think id be a fool if I said that I said I had the best seat of the three, but on the other hand I can say with complete candor and with complete honesty that I’m very happy to have the seat which I have, and to be doing the job that I intend too do." Michael Collins went on to become the Assistant Secretary of State for Public Affairs. He also become the third director of the Smithsonian museum, from 1971 to 1978.
By Clarence, @aerospace_guy © World Space Club
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Chance favours the prepared... Crew training for Apollo was more diverse than you might imagine. So, how do you prepare for a mission to somewhere no-one has ever been to before, with new and as of yet untested equipment? The Apollo crews had to train for every eventuality, in all sorts of terrain and conditions. The images on the left demonstrate just a few examples of the rigorous training routines the crews had to go through. The activities shown, in order of left to right and top to bottom are: Buzz Aldrin and Neil Armstrong participating in geology training. Apollo astronauts performing one of many training exercises in the desert. Buzz Aldrin and Neil Armstrong in a simulation of the Lunar surface. Buzz Aldrin training underwater for the Gemini 12 mission. Buzz was critical in developing the very concept of using the underwater environment as a simulator for zero-gravity. Neil Armstrong parachuting back down to Earth after ejecting from a Lunar Landing Research Vehicle (LLRV) that failed. Legend has it he went straight back to work afterwards, not worried by the incident despite having almost bit his tongue off. Neil Armstrong training with the cameras that would be used on the Moon. In his famous picture of Buzz on the Lunar surface you can see Neil in the reflection on Buzz's helmet. That is the only photograph of Neil on the Moon, as he was the cameraman. Neil Armstrong in an ejector seat about to perform high-g force training. The LLRV flying at an airport, not crashing this time. Buzz Aldrin training for his mission to the Moon in a zero-gravity aircraft. Neil Armstrong training in a LEM simulator. Apollo astronauts participating in splashdown training exercises. Michael Collins inside the Apollo Command Module looking at a checklist. Buzz Aldrin and Neil Armstrong inside a LEM simulator, practising landing on the Moon.
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By Clarence, @aerospace_guy Š World Space Club
And finally, John Young and Neil Armstrong in the jungle undergoing survival training, in case they landed on the wrong part of the Earth.
Mission control The hidden teams behind the entire Apollo program Over 400,000 engineers, scientists and technicians worked tirelessly behind the scenes to prepare for and support the Apollo 11 Moon landing. The learning curve for all those involved in this mission was steep. Many of the people involved had never had any experience of aerospace before, but they rose to the enormous and worthy challenge with huge enthusiasm, inspired by the mission's noble goals. They adapted and applied their own individual skill sets to the huge Apollo team's collective efforts, with magnificent results. Many of these individuals and sub-teams had to overcome huge technical challenges, bureaucratic problems and even tragedies. However, the Apollo program had exceptional managers, who did an incredible job of pulling everybody together and keeping everyone motivated. Throughout the flight of every mission, a vast team would be on standby, ready to offer advice & support when called upon by their line managers. Their line managers would then report to one of a series of system support rooms in Houston, which would then report directly, in turn, to one of 20 people in Mission Control (the Mission Operations Control Room, or MOCR). One person was in charge of each mission, and would receive this information from all the other 20 people in the MOCR. That was the person known by codename 'Flight'. And for Apollo 11, that person was Gene Kranz. It was thanks to all these incredible teams, working constantly to design, build, and support the spacecraft and the ground systems, and the Mission Control team, that Apollo 11 and all the other missions were successful. "We would like to give special thanks to all those Americans who built the spacecraft; who did the construction, design, the tests, and put their hearts and all their abilities into those craft. To those people tonight, we give a special thank you, and to all the other people that are listening and watching tonight, God bless you. Good night from Apollo 11." - Neil Armstrong, on the night before splashdown, July 23, 1963 Neil Armstrong: Engine arm is off. Houston, Tranquility Base here. The Eagle has landed. Charles Duke, Capsule Communicator: Roger, Tranquility. We copy you on the ground. You got a bunch of guys about to turn blue. We're breathing again. Thanks a lot. Buzz Aldrin: Thank you.
By Clarence, @aerospace_guy Š World Space Club
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Countdown to Launch In their own words... From imagination to reality... "Over 100 years ago a science fiction writer [Jules Verne] imagined that men from planet Earth would one day make footprints on the Moon. The science fiction of yesterday has become the modern history of today. That great father of modern science fiction did not precisely describe this mighty Saturn [V]. Verneâ&#x20AC;&#x2122;s projectile satellite was not nearly as sophisticated as the Apollo spacecraft, though Verneâ&#x20AC;&#x2122;s vehicle did take 3 men around the Moon in greater luxury. Can you believe that Verne propelled his earliest astronauts from Florida too? He even mentions Cape Canaveral as being the ideal latitude for Lunar launching. He gave us a vision of the space age over 100 years ago."
"You take a gamble when you tell the whole world your plans, the global audience had witnessed all our early failures, but when and if you do achieve, the whole world shares in the achievement. We knew the world was watching and listening and waiting with us. We knew we had the sympathetic thoughts of many and millions prayed." Reflections on the night before the launch... "Verne would have loved to see the Cape that day July 15th, 1969, the day before Armstrong Collins and Aldrin were going to blast off from the Earth on their journey to the Moon. His prophetic book forecast countless spectators, though he might not have visualized that a small resort like Cocoa Beach would play host to more than a million guests... The giant Saturn had not slept that night. Neither had any of the hundreds of loyal attendants, the scientists and engineers, the skilled technicians that made up the uniquely professional Apollo launch team. The leading actors in this most impressive pageant made their entrances, dressed in expertly designed costumes so vital to the success of each mans performance. The curtain was going up on what was truly the greatest show on Earth, before the largest single audience ever assembled.... In the minds of many was the emerging concept of a new era for mankind on planet Earth. Apollo in the distant past had represented dawn... " - Wernher Von Braun
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By Clarence, @aerospace_guy Š World Space Club
Dawn at the cape, July 16th, 1969. "Apollo Saturn launch control. Shortly we'll expect that astronauts Neil Armstrong and Michael Collins to come across swing arm 9, the Apollo access arm, and proceed to the white room, and extend life support to the spacecraft. The third member of the crew, astronaut Edwin [Buzz] Aldrin will be the last one to board the spacecraft, he will stand by in the elevator, & sit in a chair while his two comrades board the spacecraft. This is launch control." "Just a short while ago launch operations manager Paul Donnelly, who checked in with the crew at the spacecraft wished the crew good luck and Godspeed on behalf of the launch crew here in the firing room. The astronauts reported back "Thank you very much, we know it will be a good flight". We are still counting and we are go on the Apollo 11 count at this time. This is Kennedy launch control." "This is Apollo Saturn launch control, we are at T-10 minutes and counting, T-10 on the countdown for Apollo 11, all elements of the count still proceeding satisfactorily at this time. At this point in the countdown the prime crew for the mission, astronauts Neil Armstrong, Mike Collins and Buzz Aldrin are busy in their spacecraft at the 320 foot level above the launch pad here at complex 39." "The spacecraft is now on full internal power, on the power of its fuel cells. Up to this time been sharing the load of the spacecraft power with an external power source. We've also been keeping a close eye on the Lunar Module which will have the callsign 'Eagle' once it separates from the spacecraft in Lunar orbit. We've now powered down the Eagle and the Eagle is reported go for launch. The astronauts reported that the astronauts have armed their rotational hand controllers, and we are continuing to count. We are still go with Apollo 11 at this time. This is Kennedy launch control." "T-35 seconds and counting, countdown smooth at this time. T-30 seconds and counting, were on full internal power with the launch vehicle, Apollo 11 still go at this time." "20 seconds and counting. T-15 seconds, guidance is internal" "12" "11" "10" "9" "Ignition sequence start." "6" "5" "4" "3" "2" "1" "0" "All engines running. Liftoff, we have a liftoff! 32 minutes past the hour, liftoff on Apollo 11." By Clarence, @aerospace_guy Š World Space Club
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Mission highlights from Apollo 11 At first, the Saturn V rises of the launch pad slowly, its engines barely putting out enough thrust to lift its massive weight upwards. But soon it starts to gain velocity, flying higher and faster. As the rocket thunders upwards, spectators miles away began to hear the enormous sound of its engines rolling over them, the shockwaves traveling at the speed of sound having taken this long to reach them. Shortly after leaving the pad, the rocket rolls to face the correct direction, and starts to pitch over 9.6 seconds after launch. As the rocket brakes the sound barrier, shockwaves of condensation can be seen forming around it. Two minutes and 5.6 seconds after liftoff the center of the five F-1 engines on the S-IC first stage is shut down to reduce acceleration. 25.4 seconds later the rest of the engines on the S-IC shut down, and the rocket goes silent. Said silence doesn't last long, as 0.7 seconds later explosive bolts cut lose the S-IC and small rockets ignite to pull apart the two craft, the acceleration they cause forcing propellents to rush to the base of their fuel tanks and into feed lines. Seconds later, ignition commands are sent to the 5 J-2 engines, and they light up, propelling the S-II second stage higher and faster. 30 seconds later, the interstage skirt that shrouded the J-2 engines during launch is commanded to detach, and 5.6 seconds after that the Launch Escape Tower is jettisoned. Eight minutes and 40 seconds later, the S-II shuts down, and is cut loose. Once again small rocket motors fire to push away the spent stage and settle the propellents, and the S-IVB third stageâ&#x20AC;&#x2122;s single J-2 engine ignites. Finally, 11 minutes and 21 seconds after the rocket left the pad, the J-2 engine cuts off, and two small finecontrolled rocket motors fire for 28 seconds, pushing the Apollo stack the final few meters per second into Low Earth Orbit (LEO). Two and a half hours later, after a comprehensive checkout of the vehicles systems, preparations begin for re-starting the S-IVB. Two hours, 50 minutes and 38.4 seconds after launch the spacecraft lights up the J-2 and begins the Trans-Lunar Injection (TLI) burn, to send them onwards to the Moon. 5 Minutes later, the engine stops firing, with a Lunar flyby trajectory established. Twenty minutes after that, the S-IVB is cut loose. As the Command Service Module (CSM) named Columbia slowly drifts away from the S-IVB, it fires its Reaction Control System (RCS) thrusters to stabilize its relative movement, and begins to rotate 180 degrees around. It approaches the Lunar Excursion Module, nestled atop the S-IVB, and previously mounted below the CSM in a shroud until only a few minutes ago, when said shroud was jettisoned to detach the CSM. Columbia slowly moves in and docks to the LEM. About an hour later, explosive bolts sever the links holding the LEM to the S-IVBâ&#x20AC;&#x2122;s mounting adapter, and Columbia fires its RCS to extract the LEM, named Eagle, from the S-IVB. Around 30 hours after launch, three sequential TV telecasts are performed, during the last of which the astronauts perform an inspection of the LEM.
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By Clarence, @aerospace_guy Š World Space Club
Eighty hours, 11 minutes and 36.75 seconds after liftoff, Apollo 11 is at perilune (the point in its flyby trajectory [or orbit] closest to the Moons surface), and the Service Propulsion System (SPS) engine on Columbia fires, and cuts off 357.5 seconds later. Columbia and Eagle have just been placed in Lunar orbit. An hour later, Buzz Aldrin and Neil Armstrong leave Columbia and enter the LEM, and begin prepping for the descent. One hundred hours and 12 minutes after launch the Eagle and Columbia undock. Michael Collins, still in the CSM, fires Columbia’s RCS thrusters to back away, and Neil rotates the Eagle 360 degrees so that Mike can perform a visual inspection. The LEM looks fine, and so 24 minutes and 14 seconds later, Neil adjusts the LEM’s attitude to point away from its direction of movement, the Eagle’s descent engine ignites, slowing it down, and the vehicle starts falling towards the Moon. Just under an hour later the landing radar switches on, and 102 hours, 33 minutes and 5.01 seconds after launch the LEM descent motor ignites again, and powered descent begins. Four minutes and 40 seconds after Powered Descent Initiation (PDI), the Eagle rolls onto its back, so Neil and Buzz are facing upwards, with their legs pointing almost horizontally, in the direction of movement. Shortly after however, a problem appears. Inside the LEM’s cabin, alarms start going off...
By Clarence, @aerospace_guy © World Space Club
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The Apollo Guidance Computer (AGC) has a limited amount of Rapid Access Memory (RAM), or memory that can be rewritten. This RAM is used to run programs, and what programs will run, and in what order, is decided by the computer on a priority based system, with higher priority programs going first. The MIT engineers that built the AGC designed it to never run out of storage space for running programs, based on what programs they expected the computer to be running at any one point in the mission. But during the descent, an extra program is running in the AGC, slowly using up storage space. Back when Eagle undocked from Columba, the crew turned on the rendezvous radar to track the CSM’s position. This was only going to be used in an emergency, if they needed to abort and wanted to know where the CSM was during the ascent. They had made sure to switch the rendezvous radar onto a mode that shouldn’t have been sending data on the CSMs position unless it was needed, but unknown to them, it was sending data anyway, due to problems in the computers power supply effecting the system. This had slowly started filling the AGC’s RAM banks with useless information, and that had started getting in the way of running other programs vital to the landing. This has triggered the alarm, a 1202 program alarm signaling there is no more available memory to be specific, which is currently blaring though the cabin. The AGC, realizing it’s overflowing with data, shuts down all of its programs and reboots, fast enough not to lose stored information vital to the landing. Houston tells them they are go for continuing the descent. A few minutes later, enough data has accumulated to make the same thing happen again, with Buzz noticing a correlation between the 1202 alarm and a 16/68 code that was entered into the computer at the time. Realizing that the Verb 16 Noun 68 code, the one you punch into the computer to get it to display range to the landing site and velocity, was probably the last straw pushing the AGC over the edge, he decides in future to ask Houston for the data, and not call it up from the computer. But they aren't out of the woods yet. A few minutes later, a third alarm goes off - This time a 1201 alarm, signifying the AGC has run out of core sets to compute things. Houston again told Eagle that they are go for the landing. The 1202 alarm then came back, going off two more times. Each time the computer rebooted, wiping all unneeded data.
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By Clarence, @aerospace_guy © World Space Club
Eight minutes and 30 seconds after PDI the AGC switches to Program 64, pitching the Eagle forwards into a more upright position, and allowing Neil and Buzz to see the landing site. They are way off target, but not quite in unmapped territory yet, and the descent continues. Ten minutes and 10 seconds after PDI, the Eagle is headed towards an area covered in huge boulders, and Neil sends the AGC into Program 66, giving him full control of the spacecraft, and he begins pitching forward to maintain altitude and clear the boulder field. At this point they are about 150 meters above the surface. Eleven minutes and 53 seconds after PDI, flight calls 60 seconds to 'bingo', the point at which they run out of fuel and have to abort. Twenty meters above the surface the LEM’s descent engine starts kicking up a substantial amount of dust. With just 18 seconds to bingo, Buzz calls “Contact light", as a 1.5 meter long probe mounted to the landing legs makes contact with the Moon, lighting an indicator inside the cabin. Neil cuts the engine, and the LEM settles onto the Lunar surface at 20:17 GMT, 102 hours, 45 minutes, and 43 seconds after launch. Three and a half hours after the Eagle touched down, Neil and Buzz start preparing to exit the LEM. The preparations take several hours. At 2:39 on the 21st of July, Neil opens the Eagles hatch and starts to climb through and onto the ladder. As he descends, he pulls an o-ring to his left, which triggers a mechanism to deploy a TV camera nestled in a compartment on the side of the LEM, which now swings outwards and activates...
Neil proceeds to step further down the ladder, and stops just short of the surface, examining it, and judging the depth of the fine dust that coats it. Finally, at 2:56 GMT and 15 seconds, Neil Armstrong steps off the base of the ladder, saying the words “Thats one small step for a man, one giant leap for mankind”. As he walks away from the base of the ladder, Neil performs a short visual inspection of the Eagle’s descent stage, and collects a contingency sample of the surface, in case they need to abort quickly. Nineteen minutes later, he is joined by Buzz Aldrin, and they perform a more detailed inspection of the LEM. They then proceed to read the plaque on the LEM’s descent stage, and set up the US flag. At 3:48 GMT and 30 seconds, president Nixon calls Neil and Buzz, congratulating them, and saying he is looking forwards to meeting them on the recovery ship. The astronauts then proceed to set up three Lunar surface experiments, two of which will stay on the Moons surface after they leave. One of them, the Lunar Retroreflector, is still operating even now, 50 years later (admittedly said experiment has no electronics or other fragile components). By 5:09 GMT, both Neil and Buzz are inside the LEM again, and prepare for liftoff. Buzz says: "Houston, Roger. We're number one on the runway." At exactly 17:54 GMT, the Eagle’s ascent stage motor fires, and connections to the descent stage are severed. The Eagle rises off the Lunar surface, and begins pitching over to enter orbit. Seven minutes and 15 seconds later, the Eagle is in a stable orbit and the motor cuts off. Whilst orbiting the Moon, the Eagle performs several burns to correct its orbit and rendezvous with Columbia. At 21:35 GMT, the CSM docks to the LEM, and Buzz and Neil transfer back to the Columbia, rejoining Mike, who has this entire time been taking photographs of the Lunar surface in preparation for future landings. Mike is overjoyed to be reunited safely with his colleagues, he didn't want to have to return to Earth without them. The Eagle is jettisoned 2 hours and 6 minutes later, and Columbia fires its RCS to back away from the discarded LEM. Trans-Earth injection starts at 4:55 GMT and 42 seconds, on the 22nd of July, lasting 2 minutes and 31 seconds. During the coast back home to Earth, only one mid-course correction is needed. Three live telecasts are also performed during trans-Earth coast. As Columbia approaches the Earths atmosphere, the crew preps for CM/SM separation. At 16:21 GMT and 12 seconds, on the 24th of July, electrical signals are sent to pyrotechnic devices commanding them to fire, and to detach the umbilical connectors running between the two craft. The Service Module is cut free, and fires its RCS jets to back away from the Command Module which fires its own thrusters to align for atmospheric entry, which occurs at 16:35 GMT. The Command Module breaks through Earth’s atmosphere at 11 kilometres per second, generating temperatures over 2970 Kelvin, or 2700 degrees Celsius. This creates a wave of plasma around the Command Module that blocks communications for several minutes. Finally, at 6:44 GMT the drogue parachutes deploy, shortly followed by the main chutes. Columbia splashes down at 16:50 GMT and 35 seconds, 195 hours, 18 minutes and 35 seconds after liftoff, and is quickly recovered by the recovery ship USS Hornet, less than an hour later.
By Clarence, @aerospace_guy © World Space Club
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One Small Step
In their own words... “Mr Armstrong I do realize that when you were on the Moon you had very little time for gazing upwards, but could you tell us something about what the sky actually looks like from the Moon? The Sun, the Earth the stars if any, and so on. The sky is a deep black, when viewed from the moon as it is when viewed from cislunar space, the space between the Earth and the Moon. The Earth is the only visible object other than the sun that can be seen although there’ve been some reports of seeing planets. I myself did not see planets from the surface, but I suspect they might be visible. The Earth is quite beautiful from space, and from the Moon, it looks quite small and quite remote but it’s very blue and covered with er white lace and of the clouds and the continents are clearly seen although they have very little colour from that distance.” - Neil Armstrong talking to Sir Patrick Moore (on Sky at Night, BBC)
“We had some difficulties in perception of distance, for example our television camera, we judged to be from the cockpit of the lunar module only about fifty to sixty feet away, yet we knew that we had pulled it out to the full extension of the one hundred foot cable. Similarly we had difficulty guessing how far the hills out on the horizon might be. Peculiar phenomenon is the closeness of the horizon due to the greater curvature of the Moon than we have here on Earth of course four times greater, and the fact that, it is an irregular surface with crater rims overlying other crater rims.
“I just see it as a beginning, not just this flight but this program, which has really just been a very short piece of human history, an instant in history, the entire program is a beginning of a new age.”
You can’t see the real horizon you’re seeing hills that are somewhat closer to you. There was, a large crater which we overflew during our final approach which was .. had hills of the order of a hundred feet in height, and we were only eleven, twelve hundred feet west of that hill and we couldn’t see a hundred foot high hill from eleven to twelve hundred feet away.” - Neil Armstrong
- Neil Armstrong
30 seconds. <of fuel left> - Capcom Forward drift? - Armstrong Yes. - Aldrin Okay. - Aldrin
I'm at the foot of the ladder. The LM footpads are only depressed in the surface about 1 or 2 inches, although the surface appears to be very, very fine grained, as you get close to it. It's almost like a powder. [The] ground mass is very fine.
Contact light. <Indicating the LEM had landed> - Aldrin
Okay. I'm going to step off the LM now.
Okay. Engine stop. ACA - out of detent. - Aldrin Out of detent. - Armstrong Mode control - both auto. Descent engine command override - off. Engine arm - off. 413 is in. - Aldrin We copy you down, Eagle. - Capcom
That's one small step for [a] man; one giant leap for mankind. Yes, the surface is fine and powdery. I can kick it up loosely with my toe. It does adhere in fine layers, like powdered charcoal, to the sole and sides of my boots. I only go in a small fraction of an inch, maybe an eighth of an inch, but I can see the footprints of my boots and the treads in the fine, sandy particles.
Houston, Tranquility Base here. The Eagle has landed. Armstrong Roger, Tranquility. We copy you on the ground. You got a bunch of guys about to turn blue. We're breathing again. Thanks a lot. Capcom
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By Clarence, @aerospace_guy © World Space Club
In their own words... Magnificent Desolation “I think I'd heard the word magnificent. I can't say that that just popped into my mind. It's in the radio transmissions from Neil. I probably said beautiful, beautiful — and then he said magnificent, isn't it? And that's when maybe I responded with magnificent desolation. Now, however that came about, the meaning that was really behind that without being put into words at the time was humanity's progress to reach a point where we leave the earth and we go to that object in the sky called the moon and we walk around on it. I mean, that's a tribute to the progress, to the achievements of the human race, and it's so magnificent that we were a part of that, But looking out at the lifelessness of the scenery doing the magnificence of being there it was at such a lifeless, desolate place that I couldn't imagine any place more typical of desolation with just gray, shades of gray and a black sky and a brilliant sun and no atmosphere. And these things are in your head and radiation from the sun. It's just not a very hospitable place. And, the most important — it hasn't changed in hundreds of thousands of years. What we're looking at just a little bit more dust has accumulated. But it's been that same way for such a long time.” - Buzz Aldrin
“There were more people paying attention to the two of us, the three of us, than is usually the case when people move away from home, we tend to forget about them. But they were sure paying attention to us now, we sensed that.
Beautiful view! - Aldrin Isn't that something! Magnificent sight out here. - Armstrong
Magnificent desolation. - Aldrin [Steps onto Lunar surface] Looks like the secondary strut had a little thermal effects on it right here, Neil. - Aldrin Yes. I noticed that. That seems to be the worst, although similar effects are all around. - Armstrong [Garbled] very fine powder, isn't it? - Aldrin Isn't it fine? - Armstrong
It was such a unique opportunity that was presented to a group of us who came along as pilots, to be given the opportunity to go into space, and to go and maybe land on the Moon. What a wonderful thing that I’m here, that the two of us are doing what we were trained to do. What a magnificent achievement it has been for humanity, to come down from the tress, rummage around, as creatures invent wheels, dig things out of the ground and get metal, melt it, and fly airplanes and cars and rockets, we are walking on the Moon! What a marvelous evolution we’ve been able to achieve as creatures, from an object in space called a planet. It was sufficient demonstration of our capability, we learned quite a lot out of going to the Moon, and it is now appropriate to build on that early venture to our neighbor, and now to go to a much more bigger, a much grander objective, of another planet in our solar system. And not just to visit a couple times, but to set up a sustainable presence. Eventually humans will leave the Sun and the solar system and go to other stars. Eventually, not in my life time or yours, but we’ll learn how do do that! - Buzz Aldrin
By Clarence, @aerospace_guy © World Space Club
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From Apollo to Earth The story of the Parkes radio antenna
The Parkes radio observatory is one of the lesser known aspects of the Apollo missions, but if not for Parkes millions around the world would not have been able to watch the Moon landings live on TV. Positioned in south-eastern Australia, the radio observatory was built in 1961 and designed to search the heavens, looking mostly at other stars and galaxies. However, for the Moon landings NASA approached the Parkes team to use the telescope to receive signals from Apollo 11, since they had no other such antennas in the southern hemisphere large enough to receive video transmissions. Despite 110 kph wind gusts on the day of the landing, well over what it was designed to handle, the dish did not falter once, providing a clear signal through the entire event. It was so successful, that not only is it still in use by NASA today, NASAs Deep Space Network antennas were based of of its design. On a less serious note, in 1998 while performing astronomical observations, it detected Perytons, fast bursts of radio signals. Initially, they were thought to be signals from another galaxy... turns out they were actually caused by someone opening the door of a microwave oven. By Clarence, @aerospace_guy Š World Space Club
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Space Rocks Funny smells, potentially flammable Moon dust, and Soviet robotic sample return probes. Of all the things you usually associate with the Moon, a funny smell isn’t one of them. But thanks to the extremely fine dust that coats its entire surface, many Apollo astronauts reported smelling an ash-like oder in the Lunar Excursion Module. Harrison Schmitt said that it “Smells like someone’s been firing a carbine in here.” NASA, as it turns out, had actually considered the Lunar dust - but for a different reason. An astrophysicists at Cornell University named Thomas Gold had warned NASA that the dust had not encountered oxygen for so long it might be chemically reactive to it. If the LEM was pressurised and there was still Moon dust in it, the dust might spark or even explode. “A late-July fireworks display on the Moon was not something advisable,” Buzz Aldrin commented. So, Apollo 11 took precautions. When they came back into the LEM, Armstrong placed a small amount of dirt on the floor of the LEM, and slowly let oxygen back in. If the dust started to smoulder or spark, he would depressurise and get rid of the dust. Luckily however, nothing happened, and the dust wasn’t reactive. Thats not to say the dust wasn’t a nuisance though. It was so fine it ate away at your lungs and eyes. In fact, some astronauts when spending the night on the Moon slept in their helmets and gloves, in part to avoid breathing in the dust floating around. By the time that the rocks and dust had been returned to the Earth, the smell had disappeared. Since then, no one has been able to figure out what caused it. “Very distinctive smell, I’ll never forget. And I’ve never smelled it again since then.” - Apollo 12 commander Pete Conrad
Just before Apollo 11 lifted of on July 16, on July 13 another rocket bound for the Moon was launched - this time with CCCP written on the side of it. Luna 15 was a Soviet uncrewed probe that was supposed to land on the Moon, scoop up some rocks, and return to Earth, delivering its samples to scientists back home before Apollo 11. Unfortunately, things didn't go to plan. Even with the Soviet scientists spending a day longer than planned to choose a landing site, they still failed to identify a huge mountain in its flight path, which Luna 15 crashed into during descent. While the Soviet's probe intended to return less than a kilogram had crashed, Apollo 11 was already on its way home with over 21.5 kg of samples. All was not for nothing however, as it actually sparked the beginning of a longstanding cooperation between the US and USSR space programs. During the ordeal, NASA had for the first time, directly contacted members of the Soviet space program, and inquired about Luna 15's orbit. Amazingly, the Soviets responded, detailing its orbital parameters, and saying that it wouldn't come near Apollo 11.
By Clarence, @aerospace_guy © World Space Club
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The entire focus of the Apollo program, up to and including Apollo 11, had been to win the space race, and demonstrate the Apollo spacecraft and systems.
Apollo 12
Sure, Apollo 11 had done some science, but its primary goal was to prove that Apollo could land and take off from the Moon.
Lightning, science, and art
Apollo 12 however, that was where the scientific side of things started to get really interesting...
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By Clarence, @aerospace_guy Š World Space Club
We'd done it! Humans had landed on the Moon and gotten back safely. NASA had achieved Kennedy's goal and ensured that the first flag planted on the Moon was the American Stars and Stripes. However, for the visionary scientists and engineers behind Apollo, this was just the beginning. The space race may have funded the program, but there were still much greater goals to achieve... for the benefit of all mankind. On the 14th of November, 1969, the Saturn V rocket carrying the Apollo 12 Command Service Module (CSM), Lunar Excursion Module (LEM), and astronauts Commander Charles “Pete” Conrad Jr, Command Module Pilot Richard F. Gordon Jr, and Lunar Module Pilot Alan Bean blasted off from Cape Kennedy atop a long pillar of orange flames and white smoke. However, the day chosen for launch was not clear, and Apollo 12 flew through a rain cloud above the launch pad. Only 36 seconds into the flight, a bolt of lightning struck the Saturn V, tracing down the exhaust plume into the launch tower, with the rocket essentially having acted as the biggest lightning rod in history. The protective systems in the vehicles fuel cells, which supply power, detected an overload and took the cells offline, as well as many of the instruments in the Command Module. This left the Apollo spacecraft relying entirely on battery power, which couldn’t keep up with the energy requirements needed. One of the AC inverters dropped offline, which resulted in a cascade of failures that lit most of the warning lights in the Command Module and caused much of the instrumentation to fail. Then, 52 seconds into the flight, the rocket was struck by lightning a second time. The data mission control was receiving was chaotic, the astronauts and mission control had no idea what was going on, and if they didn’t figure out soon, the mission would have to be aborted, with the Launch Escape System (LES) pulling the capsule clear of the rocket.
Just as they were preparing to abort, one of the flight controllers, EECOM John Aaron, recognized the pattern of distorted telemetry data from an earlier simulation, and made the call "Flight, EECOM. Try SCE to Aux". Most of the guys in both mission control and the spacecraft had no idea what that meant, but Lunar Module Pilot Alan Bean did. He had been in a simulation once where the same failure had occurred, and thanks to his outstanding memory he was able to locate the switch. He reached over and hit the switch. Almost immediately the Command Module’s computer rebooted, and the telemetry uplink was restored. The quick thinking on the part of Aaron later earned him a reputation as a "steely-eyed missile man". The computer that had dropped out as a result of the lightning strike was the one in the Command Module which controls the Apollo spacecraft, however the computer controlling the Saturn V launch vehicle was positioned in the SIVB third stage, and in a testament to IBM engineering, didn’t fail when the rocket was struck by lightning. If it had, the vehicle wouldn’t have been able to stay on course while the astronauts and mission controllers tried to restore the Command Module’s computer, and the mission would have been aborted. In spite of its dramatic start, the rest of the launch was successful, and after 3 telecasts on the way to the Moon the CSM fired its Service Propulsion System (SPS) engine, and entered Lunar orbit on November 18th. The same day, Conrad and Bean entered the LEM and a telecast to Earth was made of the separation of the CSM and LEM, happening 107 hours after launch. On the 19th off November, 109 and a half hours into the mission, the LEM began powered descent. Apollo 11 had missed its landing site by several kilometres, but that was fine since it hadn't been aiming for anything in particular. Apollo 12 didn’t have that luxury. Their landing target was the Surveyor 3, an uncrewed probe that had been sent to the Moon in 1967, and as such they would have to land within a kilometre or so of it.
By Clarence, @aerospace_guy © World Space Club
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Impressively, the landing was perfect, touching down just 183 meters from Surveyor 3 on a area of the Moon's surface known as the Ocean of Storms, 110 hours and 32 minutes into the flight. Three hours after the landing and before the first extravehicular activity (EVA), or Moonwalk began, Richard Gordon orbiting 110 kilometres up in the CSM named ‘Yankee Clipper’, saw both the LEM named ‘Intrepid’ and Surveyor through the use of a 28-power sextant telescope.
Rocks returned: - 34.35 kilograms in total were returned - Two Apollo Lunar Sample Return Containers (ALSRC) (shown above) were used on each mission. This was in order to protect them during the flight. Made from Aluminum with a triple seal, and an aluminum mesh liner, the 'rock box' as astronauts called it, was closed under a vacuum on the Lunar surface so that dust and bacteria in the air wouldn't contaminate them during the return flight. Editors note: Yes, we agree. A replica of that as a lunch box would be awesome. Earth Orbit / Lunar Orbit Experiments: 1. Cosmic Ray Detector (helmets) 2. Multispectral Photography 3. Candidate Exploration Sites Lunar Mission Conrad was the first to go on EVA, and 115 hours and 10 minutes after liftoff an American astronaut was once again walking on the Moon. He was shortly followed by Bean, and together they logged about 3 hours on the surface. During the EVA, Conrad collected samples and set up an S-Band antenna and a solar wind experiment, while Bean set up a colour TV camera on a tripod. However, in the process of setting up the camera Bean accidentally pointed it at the sun, which burnt out the sensor. Yes, that’s an actual thing that happened - Astronauts (occasionally) make mistakes too! The Apollo Lunar Surface Experiment Package (ALSEP) instrumentation and SNAP-27 RTG (scientific experiments that would be left on the surface) were set up a hundred or so meters from the LEM. After the EVA was complete, Conrad and Bean entered the LEM and ate, recharged their backpacks, and slept for around 5 hours.
4. Photography from CM
On November the 20th, an hour and a half earlier than originally planned, Conrad and Bean began the second EVA. During this EVA, they collected around about 40 kilograms of dirt and rock samples. The astronauts also walked to the nearby Surveyor 3 lander, and removed various components from it of return to Earth, most notably the TV camera. They then returned to the LEM and concluded the second EVA 135 hours and 20 minutes after launch.
3. Lunar Surface Magnetometer
About 6 hours later, on the same day, the LEM’s ascent engine fired and the vehicle rose from the Moons surface, to rejoin Gordon and the CSM orbiting above. Once Conrad and Bean had transferred into the CSM, the LEM was undocked and preprogrammed to fire its engine to crash into the Moon, where a seismometer left on the Lunar surface would measure the impact. While orbiting the Moon, a heavy schedule of photographing and mapping the Lunar surface occurred aboard the CSM. Conrad and Bean returned to the CSM, the SPS was ignited and the CSM was placed on an orbital path that would return it to Earth. The return flight was mostly smooth and uneventful, with one course correction and a live telecast. On the 24th of November, the second Moon landing mission came to a close as the Command Module parachuted down to the Pacific, where the USS Hornet was waiting to recover them and give them a ride home!
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By Clarence, @aerospace_guy © World Space Club
5. Selenodetic Reference Point Update Apollo Lunar Surface Experiments Package (ALSEP): 1. Lunar Dust Detector 2. Passive Seismic Experiment
4. Solar Wind Spectrometer 5. Suprathermal Ion Detector 6. Cold Cathode Ion Gauge
From reality to imagination Alan Bean; the Apollo astronaut who put the A into STEAM By Clarence, @aerospace_guy Š World Space Club
In their own words...
We were happy. We practiced this many times on Earth, we were good at it. So we get on the Moon, We're here! It's time to do it. I reach in this little bag to get the timer. I cant find it. It's too dark, the shadows on the Moon are much darker because theres no atmosphere to bounce the light around. And I'm looking in there, and the Lunar dirt has covered this chrome release, and I cant find it. So I get down on my knees and I'm pulling out sample bags to try and find it. I cant find it.
"This is one of my favorite paintings, because this is Pete Conrad on the Moon, and this is me. And we were there! Our primary mission was to land near this Surveyor spacecraft, that had landed inside this crater some 33 months earlier. When we got there we were going to cut of the TV camera, by the way you can see its missing back there, there's the cables, and then when we got finished with that we were going to take our Hasselblad camera off our chest, take it over here and put it on this little carrier where we carried experiments and rocks, and put a self timer on it and take our picture. And we thought, boy if we do this were going to be on the cover of Life Magazine.
Artwork copyright of Alan Bean. Interview by @gleopold1
We didn't take picture but I thought, not at that time but when I left NASA to become an artist, "I'm going to do that painting", and this is just how we would have done it, it would be wonderful if it had, and I titles the painting "Fabulous photo we never took"."
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Apollo 13 "Houston, we've had a problem" Apollo 13. You’ve seen the movie... but don’t skip this article!
Launch... at 13:13 hours
Over 400,000 people were critically involved in the Apollo program, working behind the scenes to ensure that humans got to the Moon. Understandably, it's the brave and intrepid astronauts that everyone remembers and focuses on, but one mission changed all that. In Apollo 13, the amazing teams at mission control came under the spotlight, and the world saw what an incredible ground support team can do.
On the 11th of April, 1970, at the stranger than fiction - but absolutely true time of 13:13 (in Houston) Apollo 13 lifted of from the Cape. The launch and ascent went smoothly, and although the center engine of the S-II second stage shut down early, it still made it to orbit, and from there, the S-IVB third stage re-ignited to propel the spacecraft to the Moon. Two days in, the mission was still looking like the smoothest flight of the program.
The problems started early.
Fifty-five hours into the flight the crew wrapped up a 49 minute long telecast, with Lovell saying, "This is the crew of Apollo 13 wishing everybody there a nice evening, and we're just about ready to close out our inspection of Aquarius and get back for a pleasant evening in Odyssey. Good night."
Apollo 13 was supposed to unfold just like the Apollo 11 and 12 missions that came before it. The crew selected for the mission were Commander James A. Lovell Jr (Tom Hanks), Lunar Module Pilot Fred W. Haise Jr, and Command Module Pilot Ken Mattingly. However, before the mission even began, problems started to arise. A few days before the launch, backup Lunar Excursion Module pilot Charles Duke accidentally exposed the crew to German measles. Command Module Pilot Ken Mattingly had no immunity to measles and was replaced by backup command module pilot, John Swigert. However, Mattingly would later fly as Command Module Pilot on Apollo 16. There were technical problems too, the Apollo Command Service Module (CSM) had two liquid oxygen tanks that along with hydrogen tanks would supply three fuel cells. Previously the No. 2 oxygen tank was installed in Apollo 10, but in the process of removing it for modifications it was damaged. When it was repaired the oxygen tank was placed in Apollo 13’s Service Module, and tested. During these tests the tanks are half emptied. The No. 1 tank emptied fine, however the No. 2 tank, the one that had been previously damaged, only drained to 92% capacity. In order to try and fix this, engineers tried blasting gaseous oxygen through the tank’s vent line to expel the liquid oxygen, but it didn’t work. Testing was temporarily halted to write a report and resumed on the 27th of March. Again, No. 1 was fine, but the No. 2 tank didn’t empty. After consolidating with the contractor and some NASA personal, it was decided to try and boil off the liquid oxygen, by using the tanks internal heater. This worked, but the oxygen took 8 hours to dissipate, during which 65 volts of electricity was passing through the heater, which due to a manufacturing oversight hadn’t been upgraded to be able to handle that high a voltage. As such, the tank was damaged in the process. Nevertheless, the damage went unnoticed and the tank was installed on Apollo 13.
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Nine minutes later, a huge bang shook the spacecraft. Multiple alarms went off, and Swigert trying to make sense of the situation radioed the famous phrase, "Houston, we've had a problem.” Lovell came on radio and informed ground control that they have a main bus B undervolt, and they lost the pressure reading on oxygen tank two, while tank one was falling rapidly. Two of the three fuel cells had also dropped out, leaving the Command Module without most of its power. Thirteen minutes after the initial failure, yes that is another strange but true fact, amidst trying to figure out what was happening, Lovell looked out his left-hand window, and told Houston “We are venting something out into the... into space”. They realised it was the oxygen from tank one, but were unsure where the leak had occurred. In actual fact the compromised tank two had exploded and shrapnel had damaged the lines and valves running into tank one. The pressure in oxygen tank one continued to decrease, and the crew were unable to stop it. Realising the CSM was about to be out of liquid oxygen which supplies the fuel cells, and as a result, out of power, with only 15 minutes of energy left in the CSM, active Capcom Lousma told the crew to make their way into the Lunar Excursion Module (LEM), which was soon to be the only source of power, and as such, life support for the crew. Haise and Lovell quickly transferred over, leaving Swigert to perform the last chores in the Command Module. However, the LEM was currently powered down, and usually it took a long time to power up. The crew had to figure out, not only how to power it up within 15 minutes, but how to transfer the data from the CSM’s soon-to-beout-of-power guidance computer into the LEM’s guidance computer, translating all of the figures in the process to account for the fact the two spacecraft weren’t facing the same direction. By Clarence, @aerospace_guy © World Space Club
Thanks to the extraordinary efforts of both the crew and everyone on the ground checking their math, the LEM was powered up and the data transferred just in time. The LEM had effectively become a lifeboat. The goal of the mission now was to get the crew back to Earth alive. The first problem they faced were consumables; the LEM was designed for a 45 hour long mission to the Moon’s surface and back, and that needed to be stretched to 90. The supply of oxygen wasn’t a problem, the oxygen tanks of the LEM were more than enough for the return. Unfortunately, that oxygen couldn’t be transferred into the CSM’s fuel cells to make power, so it was only useful to breathe. Water however, that was a problem. Mission control estimated that they would run out of water about five hours before reentry. However, data from Apollo 11, which had not sent its discarded LEM ascent stage crashing into the moon as in later Apollo missions, showed that its systems could survive seven or eight hours without its water cooling systems active. Power was also a problem, and without the fuel cells they couldn’t make any more. There were 2,181 ampere hours in the LEM batteries. In order make it all the way to reentry they would need to figure out how to get the power requirements of the spacecraft below that which you would need to run a vacuum cleaner. Amazingly, mission control figured out how to do it in record time. Even so, by the end of the mission only about 20% of the power in the LEM’s batteries remained.
There was also one electrical close call during the mission - one of the Command Module batteries vented with such force that it momentarily dropped off the power buses. Had the battery actually failed, there would have not been enough power to return to Earth. However, above all else the one problem that is remembered most is the lack of scrubbers to remove carbon dioxide from the air. In order to remove carbon dioxide from the spacecraft, they used CO2 scrubbers, which needed lithium hydroxide canisters to function. They had enough lithium hydroxide canisters to survive the trip back, but there was a problem. The LEM and CSM had independent scrubber systems, and the one in the CSM was nonfunctional due to the lack of power. The one in the LEM took round cylinder shaped lithium hydroxide canisters, and the lithium hydroxide canisters in the Command Module were square shaped. In order to return to Earth, the crew along with mission control would literally have to figure out how to put a square peg in a round hole. Luckily, mission control found a solution, and instructed Apollo 13 to construct a contraption using plastic bags, duct tape, hoses from the space suits, and even the front page of the flight manual! Yes, you heard it right, duct tape - to quote Andy Weir’s brilliant novel ‘The Martian’; “Duct tape is magic and should be worshipped”. When it was assembled it would hopefully allow the square lithium hydroxide canisters to be plugged into the scrubbers in the LEM. The contraption worked, and soon carbon dioxide levels were back within acceptable limits. By Clarence, @aerospace_guy © World Space Club
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Consumables like power, water, oxygen, and CO2 scrubbers were not the only problems however. When power was lost in the CSM, the guidance programs had to be transferred to the LEM. This was completed successfully, and allowed them to fire the LEM’s descent engine around the far side of the Moon to adjust their trajectory back to Earth. After the burn was completed, the guidance computer was shut down to save power. After all, it’s not like they would need to do a second engine burn, right? So, during their coast to Earth they realised they were slightly off course and would need to do a second engine burn.
To add even more to the list of problems, the Command Module had water condensation all along every surface, and behind the control panels along the electronic systems, threatening to short circuit something. Thankfully though, thanks to the safeguards built into the capsule after Apollo 1, the power up of the Command Module didn’t result in a short. Lovell later said about the reentry; "The droplets [of water condensation] furnished one sensation as we decelerated in the atmosphere: it rained inside the CM."
The guidance computer was offline however, and powering it up would require them to know their location and orientation in space, which they couldn’t figure out because the amount of debris around the vehicle messed with their star observations. And so, they would have to figure out how to do the burn without the guidance computer. Luckily, the burn in question had to be performed with the vehicle facing away from the Earth, and so by keeping the Earth in there downwards facing windows in the LEM they knew they were pointing the right way. And so, the LEM descent engine was fired, and the crucial burn was carried out successfully. On top of all that, there was also the fact that the lack of power available meant the heaters had to be shut down, meaning for most of the return the temperature inside the craft was a chilly 3 degrees Celsius. But above everything else, the most impressive achievement of mission control was just how quickly they developed procedures for powering up the CSM after its long period without power. The Service Module was dead, and so the energy to power up the Command Module would have to come from the Command Modules three reentry batteries. The batteries alone didn’t have enough power, and so they had to come up with a plan to transfer some power to the CSM from the LEM. Usually it would take three months to write the documents for this. The flight controllers did it in three days.
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Four hours before reentry, the Service Module was jettisoned. Mission control had insisted on keeping it attached up to that point because everyone feared what the cold of space might do to an un-sheltered heat shield. This allowed the crew to take photos of the side of the Service module as it floated away, revealing the extent of the damage. An entire side of the module had been blown out, from the engine right up to the heat shield. Three hours later, the LEM (named ‘Aquarius’) was detached, to burn up in Earths atmosphere. During reentry plasma around the spacecraft blocks communication. During the reentry of Apollo 13, this ‘plasma blackout’ lasted a few minutes longer than expected, which coupled with concerns about the heat shield being damaged in the Service Modules explosion, caused a lot of anxiety in mission control. However, in the end it was fine, with the Command Module splashing down safely in the Pacific, near Samoa. Although, nobody ever figured out what caused the blackout during reentry to last as long as it did. After the incident occurred, an accident review board was created. After a long and intensive investigation, the cause of the explosion was found. In 1965, Apollo 13’s CSM had been improved to be able to handle 65 volts in the tanks heaters, as opposed to 28 volts. However, the thermostatic switches in the tanks were not upgraded, and due to being exposed to the high voltage over a long period of time they welded shut, and the nearby wiring started to melt. All of this combined essentially made it a potential bomb the next time it was filled with liquid oxygen. That bomb went off on April 13 (I'm not even going to bother to point it out this time), 1970 - 320,000 kilometres from Earth. By Clarence, @aerospace_guy © World Space Club
Apollo 14 A golf course like no other On February the 6th, 1971, Apollo 14 lifted off from Cape Kennedy. This time NASA was back on form, and after entering Lunar orbit, on February the 5th, the Lunar Excursion Module (LEM) named Antares made the most precise landing in the entire program, touching down 30 or so meters from the target in the Fra Mario crater just about 200 kilometres from Apollo 12’s landing site. Just to reiterate that point, we managed to, using technologies from the 60’s, launch a tin can riding the shockwaves from a barely controlled explosion, from the Earth to the Moon 380,000 kilometres away, and then used another barely controlled explosion to cushion a landing only three bus-lengths from their target, with the crew alive and well! Having made a spectacular landing, due to some communications system problems, the first period of EVA began almost one hour later than scheduled with Commander Alan Shepard, who was also the first American in space in 1962 (in the Freedom 7 capsule) becoming the 5th man to set foot on the lunar surface 114 and a half hours after the mission began. The first of the two EVA’s included deploying the Apollo Lunar Surface Experiment Package (ALSEP) and lasted for four hours, 49 minutes. The second EVA on February 6th began when the LEM’s hatch was opened at 4:15 a.m. EST. During this EVA, Shepard and Edgar Mitchell moved more than a kilometre from their LEM, conducting selenological investigations, collecting samples and attempting to reach the rim of Cone Crater, approximately 100 meters above the landing site.
However, when they were about 50 to 75 meters from the crater rim they were advised by mission control to collect samples at that spot and begin their traverse back to the LEM. The second EVA lasted for four hours, 35 minutes, and Shepard set a new distance traveled record at approximately 3000 meters. During the second EVA, Shepard had also brought along a golf club, which he used to hit two golf balls over 200 meters. Never before in human history had someone traveled so far to visit a new golf course! Across both of the EVA’s, the astronauts collected 42 kilograms of rocks and soil samples for return to the Earth. As well as the surface experiments, Stuart Roosa orbiting in the Command Service Module (CSM) also did some great science during the period when the astronauts were on the surface. However he experienced a few problems with the Hycon Lunar Topographic Camera while trying to take photos of the Descartes area, the landing location that was planned for the Apollo 16 mission. After all of the surface activities were over, and it was time to return home, Antares lifted of from the Lunar surface right on schedule, and docked with the orbiting CSM. A few days after trans-Earth injection, the command module named Kitty Hawk splashed down safely in the Pacific Ocean at 4:05 p.m. EST Feb. 9, exactly nine days and two minutes after launch.
By Clarence, @aerospace_guy © World Space Club
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Apollo 15 To drive across another world Apollo 15 launched from Launch Complex 39 at Cape Canaveral at 9:34 a.m. EDT, only 187 milliseconds off schedule (but who’s counting), on a mission that would literally turn Jeremy Clarkson, Richard Hammond and James May green with envy! On July 30, 1971, David Scott and James Irwin flew their LEM named Falcon down to the Lunar surface at 6:16 p.m. EDT, at Hadley Rille about 450 meters north-east of the selected landing point near a crater named Salyut. The landing approach over the Apennine Range - one of the highest on the Moon - was at 26 degrees, the steepest yet encountered in an Apollo mission. But this time the crew didn't intend to explore on foot. This mission would take Lunar exploration up a gear. Apollo 15 was the Moon mission when the Dune Buggy had landed! Astronauts had wheels! Or more specifically, the Lunar Roving Vehicle (LRV). The LRV was used to explore a significant distance from the LEM, and they drove a total of over 27 kilometres in it. The LRV was actually capable of going much further distances than the astronauts with their mere mortal limbs could manage, however, NASA had a strict rule that prohibited driving any further away from the LEM than the crew could manage to walk back, as there were no Lunar tow-truck services available at that time! During three EVAs on the Lunar surface on July 31, and Aug. 1 and 2, Scott and Irwin completed a record 18 hours, 37 minutes of exploration. They also deployed the Apollo Lunar Surface Experiment Package (ALSEP), took a core sample from 3 meters beneath the surface, collected 77 kilograms of rocks, provided extensive oral descriptions and photographic documentation of geologic features in the vicinity of the landing site. On Aug. 2, the LEM Falcon fired its ascent stage engine and lifted off the Moon for its rendezvous with the Command Service Module (CSM) named Endeavor, leaving the Dune Buggy behind on the Moon, taking advantage of the free parking facilities. For the first time, the lunar liftoff was seen on Earth via the LRV’s television camera. The two spacecraft docked as Endeavor began its 50th lunar orbit, and later while orbiting the Moon, the Apollo CSM released a small satellite from its experiment bay, designed to monitor the Moon even after the CSM returned to Earth. On August 4th, a two and a half minute burn of the Service Propulsion System (SPS) engine put Endeavor back on a course for Earth. The next day, on August the 5th, Alfred Warden clambered out of the Command Module and down the side of the spacecraft to retrieve data from the CSM’s experiment bay, in the process conducting the first ever EVA in deep space. The EVA was completed in 18 minutes, despite one hour being scheduled in the flight plan. At 4:46 EDT on August the 7th, the Endeavor splashed down in the Pacific, ending the 12 day and 7-hour flight.
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By Clarence, @aerospace_guy © World Space Club
Apollo 16 The Lunar Grand Prix On the 16th of April, 1972, Apollo 16 lifted of the ground atop its Saturn V booster, and onwards towards the Moon. Despite minor problems with the Command Service Module (CSM), on the 20th of April the Lunar Excursion Module (LEM) carrying John Young and Charles Duke touched down at Descartes about 276 meters northwest of planned point at about 9:24 p.m. EST. During the 71 hours and two minutes surface stay, the astronauts explored the surrounding region on three EVAs totalling 20 hours, 14 minutes. On the first EVA the second Lunar Roving Vehicle (LRV, Apollo 15 being the first) was deployed, along with the Apollo Lunar Surface Experiment Package (ALSEP). Unfortunately the heat flow experiment was lost when Young tripped on an electronics cable, breaking it. The astronauts then drove over to a nearby large crater where they collected samples and photographed the area. On the return they drove south of the outbound track, towards Spook Crater where they took measurements with the Lunar portable magnetometer, took photographs, and gathered some surface samples. They then set up solar wind composition experiment at the ALSEP site before reentering the LEM. The time they had spent on EVA was seven hours and eleven minutes, with 4 kilometres of driving. During the first EVA, John Young performed a series of tests where he pushed the LRV to its absolute limits, performing s-turns and hard stops over rough terrain. This was later nicknamed the 'Lunar Grand Prix'. Their second EVA started with a drive to Stone Mountain in the Lunar rover, where they took both surface samples and core samples, along with a trench sample. They also gathered photos and pentameter readings, before then returning to LEM and finishing the second EVA after seven hours, twentythree minutes, and having traversed 10 kilometres in the LRV.
On the third and last EVA the astronauts drove north, towards North Ray Crater where ‘House Rock’ inside the crater rim, was sampled. When returning southwards, they stoped at ‘Shadow Rock’ to sample it as well. Finally, they stoped near the LEM to add further samples and core tubes to the collection. The last measurements of the Lunar portable magnetometer were gathered at the LRV’s parking site, as well as the last surface and rock samples. They then retrieved the solar wind composition and film from the far ultraviolet camera/spectroscope. The EVA was completed after five hours and 40 minutes. They had traversed 11.4 kilometres in the rover. Meanwhile in orbit Thomas Mattingly had cameras and Scientific Instrument Module (SIM) bay instruments operating during the surface stay of Young and Duke. The data he gathered verified data from Apollo 15 and provided information on lunar terrain not previously covered. On April the 23rd, at 8:26 p.m. EST the ascent stage of the LEM fired and it rose from the Lunar surface. After docking with the CSM, transferring over the samples, and having the LEM be jettisoned, the Service Propulsion System (SPS) engine fired and threw Apollo 16 back on a course to Earth. During the coast back, Mattingly took an 86 minute long EVA to retrieve data from the SIM bay. The capsule splashed sown in the Pacific just before 3 a.m. EST. The total time since launch was 265 hours, 51 minutes, and 5 seconds.
By Clarence, @aerospace_guy © World Space Club
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Apollo 17 The last Apollo mission
Think about this; just ten years earlier JFK had, under the advice and influence of Wernher Von Braun, set this seemingly impossible challenge, which many people even at NASA thought was never going to be completed in time. They knew it wasn’t going to be easy, that it would be hard, and it was... insanely hard. But with unwavering commitment the entire NASA team and the 400,000 people who worked on the missions overcame all of those challenges. Not only did they achieve their goal, but they managed from the terrible fate of the Apollo 1 crew, through to the safe touchdown and return of the Apollo 11 crew, to become so competent that by the time of the Apollo 17 mission NASA had truly started to make it look easy. Indeed, to the point where the author of this article finds himself writing that by Apollo 17, this incredible 380,000 kilometre journey from the Earth to the Moon was uneventful. I’m almost tempted to say nothing much happened. That's how far we had progressed in only one decade! It was at that point, when a mission to the Moon became seemingly routine, that space exploration had truly transcended from imagination to reality. Which makes it even more sad when you consider Apollo 17 was to be the last mission in the Apollo program. Despite getting this amazing ability to routinely travel to the Moon and back, the Apollo program was still cancelled due to budget cuts after just 5 Lunar landings. On December the 7th, 1972, at 12:33 a.m. EST the last Apollo mission thundered off the pad from Cape Kennedy. Riding atop the massive Saturn V booster were astronauts Commander Eugene A. Cernan, Lunar Module Pilot Harrison H. Schmitt, the first ever civilian scientist to fly on an Apollo mission, and Command Module Pilot Ronald E. Evans. After an 'uneventful' trip to the Moon, on the 11th of December, the Lunar Excursion Module (LEM) Challenger undocked and began its descent to the Lunar surface.
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At 7:54:57 p.m. December 11th, Challenger touched down on the Moon. Cernan and Schmitt performed three EVAs, lasting a total of 22 hours and 4 minutes. Schmitt, being a geologist, had some unique insights into preforming the scientific surface operations and deciding what rocks and surface samples to collect. On the 4th of December, at 5:40 a.m., a human stepped on the Moon for the last time in the Apollo program. Challengers ascent engine fired at 10:54 p.m., and the last Apollo LEM to land on the Lunar surface lifted off, and flew into orbit. The Command Service Module docked to the LEM at 1:10 a.m. The return flight, like the outwards one, was smooth and drama free, with Evans preforming a deep space EVA to retrieve data from the CSM’s instruments. On the 17th of December, 1972, at 2:25 p.m., the final Apollo mission came to a close as the Command Module splashed down in the Pacific, 6.4 kilometres from the recovery ship. A crucial part of space history, the pioneering age, had just come to a close. By Clarence, @aerospace_guy © World Space Club
The end of Apollo Dawn of the post-pioneering age
With the crew of Apollo 17 safely back on Earth, the last crewed Lunar spaceflight had ended, and with this last mission the pioneering age of spaceflight, - where we made more new developments and progress in a few short decades than we had in all the previous centuries combined - drew to a close, and the postpioneering age began. The Apollo program wasn't completely over yet, though. There was still some hardware left over, and while it wouldn't fly under the name Apollo, the Skylab space station did use Apollo Command Service Modules (CSMs), and a Saturn V. And then there was the Apollo-Soyuz test project, where an American Apollo CSM would dock to a Soviet Soyuz in Low Earth Orbit (LEO), becoming the first true international space mission. But, even if Apollo hardware prevailed for a few years, the glory days of the program were long in the past. By the 1980s, the Space Transportation System, also known as the space shuttle, was NASAs main and only way of putting crews into space. Originally intended to be reusable and cheap, the space shuttle was neither. The shuttle was good for building space stations, and even acting as a mini space station, but it never got to its full potential, and the shuttle derived heavy lift vehicles that promised to get us to Mars by 2000 never happened. The post-pioneering age did have a lot of successes, like the International Space Station, Hubble space telescope, and the many probes we have sent to Mars and the other planets. But it also marked the end of a brief period in human history when we had the capability to put humans on another world, and that capability is only just starting to return, a full 50 years later. We can only speculate upon what could have been achieved had the funding for Apollo not been cut. We like to imagine that we would have had Moon bases by now, and might have even pushed on to Mars, but we can't really know for sure. And even if that assumption is correct, it would have almost certainly come at the cost of most of our robotic missions to the outer planets, and maybe even the ISS. Whether or not that trade was worth it, we can never know (or agree on), but what we do know is that the excitement felt during that brief period, as well as the blazingly fast rate of innovation, was a shining example of humans at their best. By Clarence, @aerospace_guy Š World Space Club
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The future Dawn of the expansion age
In recent times things have been changing rapidly in the space industry. Private space companies, competing ultra-heavy lift vehicles, and a new goal to get back to the Moon by 2024. Humanity is just now reaching a point where it has the capability to start expanding exponentially beyond its home planet. As the coming years pass, we will almost certainly see a new golden, or perhaps even titanium, age of space exploration, cumulating in crewed voyages to the Moon, Mars, and beyond, and possibly even the creation of large scale settlements there. In our next edition of Xplore Space, we will be taking an in depth look at this topic, examining the different companies and technologies, rockets and programs, that will be used to continue expanding human space exploration into the future. Image Credit: James Vaughan / SpaceFlight Insider
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By Clarence, @aerospace_guy Š World Space Club
Image Credit: SpaceX
Extra
Journey to the Moon - Part 1
The five F-1 rocket engines on the Saturn V ignite, and the rocket ascends upwards, quickly gaining speed as it flies higher and higher through the atmosphere. Sitting atop it are astronauts Buzz Aldrin, Neil Armstrong, and Michael Collins.
Once the first stage of the Saturn V rocket is out of fuel, it no longer serves a purpose and it is cut loose, while the second stage ignites.
The Launch Escape System is a small rocket motor mounted above the capsule to pull it away from the rocket in an emergency. It is now no longer needed, and is jettisoned.
The second stage runs out of fuel and is cut loose, and the third stage ignites.
The third stage only needs to provide the final push to reach orbit, and shuts down with most of its fuel still left.
After a few hours, the third stage is relit and thrusts Apollo 11 onwards to the Moon, using up its remaining fuel.
The Command Service Module (CSM) with the crew inside separates from the third stage.
The CSM turns around, and faces the Lunar Excursion Module (LEM - named the Eagle) mounted atop the third stage.
The CSM moves forwards and docks to the LEM.
By Clarence, @aerospace_guy Š World Space Club
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Journey to the Moon - Part 2
The LEM and third stage separate, and the CSM pulls the LEM away from the third stage.
After coasting towards the Moon for 3 days, the CSM fires its Service Propulsion System (SPS) engine to enter Lunar orbit.
The CSM and LEM are now in Lunar orbit. Astronauts Buzz Aldrin and Neil Armstrong climb from the CSM into the LEM (leaving Michael Collins alone in the CSM) and begin to prepare for the landing.
The LEM and CSM separate from one anther, and the LEM prepares to de-orbit and land.
The LEM fires its engine and begins descending to the Lunar surface, specifically, a place called the Sea of Tranquility. During the descent, alarms start blearing inside the cabin, but with the help of mission control the problem is fixed and the descent continues.
The LEM hovers above the landing site for a while, searching for a place to set down that isn't covered in boulders and huge craters.
With only 18 seconds of fuel left for the descent, the LEM touches down on the Lunar surface. Buzz Aldrin speaks the first words from the Moon, "Contact light", with Neil Armstrong then saying "Houston, Tranquility base here, the Eagle has landed."
Neil Armstrong climb's down the ladder and steps onto the Moon, saying "Thats one small step for a man, one giant leap for mankind". He is shortly followed by Buzz Aldrin, and the two explore the Lunar surface, and raise the American flag.
After staying on the Moon for 20 hours, its time to return. Buzz Aldrin and Neil Armstrong climb back into the LEM and blast off into Lunar orbit.
By Clarence, @aerospace_guy Š World Space Club
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Journey to the Moon - Part 3
The LEM and CSM approach each other and dock.
Buzz Aldrin and Neil Armstrong climb back into the CSM and reunite with Michael Collins.
The LEM, its usefulness expended, is jettisoned.
The CSM fires its SPS engine and sets a course for Earth.
Three days later, the Service Module and Command Module separate from each other.
The Command Module re-enters the Earths atmosphere, going at an amazing 11 kilometres per second, so fast that temperatures reached thousands of Kelvin.
As the Command Module falls to Earth, the drogue parachutes deploy to slow it down.
Three main parachutes now deploy, further slowing its fall.
The Command Module splashes down in the Pacific, and Buzz Aldrin, Neil Armstrong and Michael Collins are recovered by the USS Hornet.
By Clarence, @aerospace_guy Š World Space Club
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In Their Own Words “And in those days we were just beginning to get into the Saturn program - that big rocket that made a lot of noise and got everyones attention. And so, once the President had made this commitment to go to the moon, we began to ground test our Saturn rockets, and my job was to take the press to the test site, and bring them up close and let them watch the test firing. I had this one reporter from New York, who came to see a test firing, and he setup his camera, he was going to record the entire test, and this was the closest I had ever brought a newsman to the test stand, and in fact I was told by my boss ‘bring the guy as close as you can because we want to really impress him’. So I did, we were about 2000 yards away from the Saturn test stand, and we were hooking up, and I began to explain to this reporter ‘look, were very close to this machine, and when this goes off you’re going to see a lot of flame, you’re going to feel a lot of vibration, you probably may want to go back further and get some shelter’. And he said ‘Young man, I’ve been all over the world, I’ve covered floods, I’ve covered tornados, I’ve covered war stories, I think I can handle this little rocket engine firing’. So, we waited for all the bells and whistles to go off, as they did in the test lab, warning everybody that we were about to fire, and sure enough they turned that big Saturn V booster on, and for a few seconds the flame just hangs there, and all of a sudden just blows out. The reporter not only knocked over his camera, but he ran across the cotton field, and did not get one foot of footage of the Saturn V test stand. I was able to go back and get some footage and give it to him. I never heard from him again, I don’t know wether he used it or not, but I know that was an interesting experience for our reporter that came to see our Saturn V test firing.“ - Ed Buckbee
The Mighty Saturn V It took a rocket as big as Saturn to get us to the Moon 45
By Clarence, @aerospace_guy © World Space Club
Trailblazer Margaret Brennecke was the first female welding engineer to work in the Materials and Processes L a b o r a t o r y a t N A S A’s Marshall Space Flight Center. She was an important member of the Saturn V team, making critical decisions on the selection of lightweight high-strength metals and welding techniques for the Saturn rocket stages. Brennecke's expertise was required to solve the problems of getting the required heat treatments, cold work, and metallographic structure to achieve high strength and reliability in thick aluminum welds of cryogenic fuel tanks. © NASA
Saturn V Meet the most powerful rocket ever built The mighty Saturn V. The biggest, most powerful, most capable rocket ever built. Taller than the Statue of Liberty, more powerful than 80 Hoover Dams, and capable of launching 140 tons, the weight of ten schoolbuses, into orbit. Propelling it’s first stage were 5 of the most powerful rocket engines ever conceived, each one eating through an incredible 5 tons of fuel per second. The fuel in question was RP-1, which is a highly refined type of kerosene, similar to the fuel used in jet aircraft. But fuel can’t ignite without oxygen, and there is no air in space. So the Saturn V carries its own oxygen along with it, in liquid form. The first stage contains 770,000 litres of RP-1 and 1,200,000 litres of liquid oxygen. But the Saturn V didn’t just have one stage. In fact, it had three. The first stage, called the SIC, was used to get the rocket going high and fast. Once its fuel ran out, it was cut loose and the second stage, called the S-II, ignited. The S-II was slightly shorter than the S-IC, and while it also had 5 engines, they were much less powerful. That got the rocket almost all the way to orbit, but it ran out of fuel just short, and after it two was cut loose the third stage, called the S-IVB, would give the vehicle the final push to reach orbital velocity. Unlike the first stage, the second and third stages were powered not by RP-1 and liquid oxygen, but by liquid hydrogen and liquid oxygen, and while that fuel type is considerably more difficult to handle than RP-1, since it need to be stored at very low temperatures, it does provide a significant increase in efficiency. Once in orbit, the third stage shut down, but since the S-IVB had only provided the very last push to orbit, it still had most of its propellent left. And so, a few hours later, the third stage would re-ignite and send itself and its payload, the Apollo spacecraft, onwards to the Moon. After a Trans-Lunar injection (TLI) burn of a few minutes, it would shut down once more, and be discarded, leaving the Apollo to continue onwards and complete its mission. All in all, the Saturn V flew 13 times only suffering one partial failure, on the uncrewed Apollo 6 mission, where vibrations, called Pogo oscillations caused by combustion instability, ruptured fuel lines in two of the second stage's engines, but the vehicle managed to limp to orbit nonetheless. The problem was almost completely fixed on future missions, although Apollo 13, in an event completely unrelated to the one you’re probably thinking of, did suffer from a less pronounced version of the same problem. The first 12 of those thirteen flights were on Apollo missions. First there was Apollo 4, an uncrewed test of the Saturn V with a dummy payload. The second flight, Apollo 6, was also an unmanned test. Apollo 8 was the first crewed flight, and it sent its crew in their Apollo spacecraft around the Moon. Apollo 9 was a crewed test of the Apollo lunar lander in Earth orbit, and Apollo 10 was a manned test of the Apollo lunar lander in Lunar orbit. Apollo 11, well, you already know about that one, as well as Apollos 12 through 17. The final and thirteenth Saturn V launch was a modified variant of the Saturn V, where the third stage was replaced with a space station, called Skylab, which it launched into Earth orbit. After Skylab, the Saturn V was retired due to budget cuts, and NASA began work on a more long term space launch architecture - the Space Shuttle, which could only go into Earth orbit. By Clarence, @aerospace_guy © World Space Club
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Apollo CSM/LEM We take a quick look at the Apollo Spacecraft Having a big rocket to get you on a course for the Moon is good, but useless without a spacecraft to make to journey in. And so, thats where Apollo comes in. The Apollo spacecraft had three major components, the Command Module (CM), the Service Module (SM), and the Lunar Excursion Module (LEM, sometimes referred to simply as the Lunar Module or LM). The CM was the capsule the astronauts lived in during the trip to the Moon and back. The SM contained the engines and fuel tanks to propel the Apollo spacecraft, as well as the life support systems supplying the CM. The LEM was a fully functioning spacecraft in its own right, which would make the perilous journey from Lunar orbit to the Moonâ&#x20AC;&#x2122;s surface, and back to Lunar orbit. During launch, the LEM would be stored in an adapter below the CM and SM combo (referred to as the Command Service Module, or CSM). When the Apollo spacecraft was on its way to the Moon, the CSM would separate, turn 180 degrees and dock to the LEM, before extracting it from the adapter. Once they arrived at the Moon, the SM would fire its engine, called the Service Propulsion System (SPS), to enter Lunar orbit. Two of the crew would transfer to the LEM, which would then undock, and land on the Moon. After a short stay on the surface, at most 2 days, the top portion of the LEM would lift of from the Lunar surface, and rendezvous and dock with the orbiting CSM. The crew would crawl back into the CM, and the LEM would be jettisoned. The SPS would again fire to send the CSM back to Earth. As it approached Earths atmosphere at a blazingly fast speed of several kilometres a second, the SM and CM would separate, and the CM would use its heat shield to protect itself as it re-enters the Earths atmosphere. Finally, a set of parachutes would deploy, and the astronauts would splashdown in the ocean, to be recovered. By Clarence, @aerospace_guy Š World Space Club
The Apollo CSM was manufactured by companies North American Aviation and North American Rockwell, and cost 3.7 billion dollars, about 39.3 billion in 2019, to develop and produce. The LEM was manufactured by the Grumman Aerospace Cooperation, and development and production cost 2.2 billion dollars, around 22.7 billion in 2019.
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Text & illustrations by Clarence, @aerospace_guy
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Space Suit The A7L - A new generation of Space Suit Technology An important component of the Apollo mission architecture was the space suit after all, the astronauts would need a way of exploring the Lunar surface beyond their Lunar Excursion Module (LEM). But designing a space suit is no easy task, and the Apollo space suit would be especially difficult. A space suit has a higher pressure on the inside than the outside so they have a tendency to ballon out and make it impossible to move - even if you make the limbs and torso out of a rigid material the joints are always very stiff due to the pressure differential. The spacesuits that would be worn on the Moon needed to be flexible and lightweight, but that wasn’t going to be easy. The contractor chosen to make the suits was the International Latex Corporation (ILC), which, while most well known at the time for producing women’s undergarments, had experience with constructing helmets and partial pressure suits for the Air Force and Navy, as well as experience working with rubber and similar materials. Each Apollo suit was constructed by a team of highly experienced and extremely talented seamstresses, who had to be very precise - any deformity in the suit larger than 0.7 millimetres could lead to catastrophic failure. They also had to invent new materials, like Beta cloth, an extremely temperature resistant fabric made of Teflon-coated glass microfibres that could resist over 800 Kelvin, which was required after the Apollo 1 fire. The biggest hurdle however was how to make the suit hold atmospheric pressure without ballooning out and becoming inflexible. In order to do this NASA and ILC engineers came up with a new idea, called the bellow joint. The suit would be made of a flexible material, and to prevent it from ballooning outwards it would have rigid metal rings positioned through the suit that held the material in the correct shape - and at the joints, there would be dozens of these rings close together. It worked, and the space suits that astronauts would later wear on the Moon would use this system. By Clarence, @aerospace_guy © World Space Club
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So, how does one go about donning (putting on) an Apollo spacesuit? Very carefully! Checking and double checking everything as you go. However, just in case of an emergency astronauts were trained to be able to don their suit in less than 5 minutes. LIke the rest of us, astronauts put their underwear on first. But Apollo briefs were nothing like our Calvin Kleins. Designed to be super absorbent, and snug, they also had built in urine collection devices. The next layer was a Liquid Cooling Garment (LCG). Basically, it was a space onesie that had a network of rubber pipes going through it. Through these pipes ice cold water was pumped, to cool the astronauts down. Attached to the LCG were biobelts, belts that had many electronic medial instruments attached to monitor the astronauts health. Undergarments on, it was now time to suit up! The Integrated Thermal Micrometeoroid Garment (ITMG) would be the next thing to don. The ITMG was basically the bulk of the space suit, and consisted of the main layer that would hold in pressure, and protect from micrometeorites. It also had several ports and bellow joints built into it. In order to don the ITMG, the astronaut would have to climb in through a zipper on the back, and it would be a very tight fit, requiring the astronaut to maneuver multiple limbs simultaneously. Once inside the ITMG, the astronaut would now start connecting all the various umbilical connectors between the LCG, the biobelt, and the ITMG. Once this is done, the astronaut would start to seal the suit, closing the large pressure zipper. With this completed, attaching all the accessories came next. The first one the astronaut would don is the Communications Carrier Assembly (CCA), also known as the Snoopy cap for its white and brown markings. The CCA was a headset that held microphones and speakers to allow the astronauts to talk to each other and to the Earth. Once that was done the astronaut has to put on his gloves. Two types of glove were available, IVA gloves for operations inside the spacecraft, and EVA gloves for operation on the Lunar surface. Next up, the helmet. The helmets for Apollo space suits were made of clear polycarbonate, and resembled fish-bowls. On the Lunar surface, a Lunar Extravehicular Visor Assembly (LEVA) was worn on top of the helmets. The LEVA consisted of a assembly that acted like a huge pair of sunglasses, protecting the astronaut from the extreme light from the sun. The next and last thing was the Portable Life Support System (PLSS) backpacks, which contained all of the systems the space suits needed to operate. By Clarence, @aerospace_guy Š World Space Club
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Have You Joined World Space Club Yet?
World Space Club is a new and exciting space club run by teenagers, but supported by some of the biggest names in space. It is aimed primarily towards young people still at school, or those just starting university, although there are no age restrictions and anyone can sign up for our free newsletter and magazine. We provide a global space hub through which talented young people who are passionate about space and STEAM can connect with one another, find mentors, connect with education providers and industry, form teams to take part in projects and competitions, and make friends and network with other WSC members all around the globe. World Space Club is free to join, and we do not charge for any of the courses or resources that we provide, including our quarterly magazine, Xplore Space. To join World Space Club, visit our website at worldspaceclub.com, and scroll down to the sign up section.
Xplore Space VOL. 02 A Sneak Peek At What's Coming Next...
