parsEc Black Holes for Beginners: They aren’t just giant space vacuums...
ICE IN SPACE The amazing properties of an everyday material!
8 MISSIONS TO SPACE
Missions that have shaped our view of the universe
LEARN HOW THE UNIVERSE BEGAN Explore different theories on the origins of the universe
Image Courtesy of Wikipedia
LETTER fRoM The EditoR Dear Reader, Astronomy is a field constantly modified by new findings, and it was also the one thing that all of the writers of this magazine had in common as we came together as a group. Coming to an agreement on things was the biggest challenge our editors faced this spring. Each person had distinct taste. For this issue of our magazine, we all pursued our own unique interests in the vast field of astronomy; and as a result, the topics of our magazine range from astrogeology to astrophysics in order to cater to all of our readers’ interests. From the minute we all met to collaborate on coming up with magazine theme, I had numerous doubts about how our magazine would turn out. Somehow though-through five months of arguing, shooting down ideas, and layout critiques-we managed to put together a a magazine that is interesting enough to to attract both non-space-enthusisasts and casual astronomers. Our goal is for this issue to leave readers a little bit less ignorant about astronomy. Of course, we owe all of our success to the professors and scientists who took time to answer our numerous questions and to explain complicated topics such as quantum mechanics to our amateur selves. Hopefully, you’ll be less amateur by the end of this issue too. Neha Sangana
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ContEnts 6 Michael Taleff
8 Coutesy of the Wikimedia Foundation
Gustavo Jaramillo
12 Coutesy of the Wikimedia Foundation
Gustavo Jaramillo
14 Coutesy of the Wikimedia Foundation
Neha Sangana
18 Coutesy of the Wikimedia Foundation
Neha Sangana
20 Coutesy of the Wikimedia Foundation
Shubhanga Ballal
24 Coutesy of the Wikimedia Foundation
Shubhanga Ballal
26 Coutesy of the Wikimedia Foundation
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Michael Taleff
revolutionary flybys and Orbiters
A guide to the the most important unmanned missions that have explored our solar system and beyond.
The origins of the Universe
The Origins of the Universe provides important views of theories that will predict the future of our universe.
The Life and death of a Star This step by step path provides an explanation of the various phases of life a star goes through from its birth to ultimate demise.
black Holes for beginners
Black Holes for Beginners provides readers with an overview of black holes, explaining everything one needs to know about these space monsters.
White Holes and Wormholes
This overview of white holes and wormholes looks at the charectoristics of these theoretical objects.
Exohunt: The Search for Another Earth Exohunt explains the various techiniques for finding these elusive bodies and the environments they may harbor.
deep Space Industries
Deep Space Industries is a new pioneering company which aims to extract valuable materials from the millions of asteroids in the solar system.
The key to Us: Extraterrestrial ICe Extraterrestrial Ice is an exciting field of astronomy where scientists can observe the properties of this solid and learn more about the solar system’s formation.
MAGAzinE StAff Neha Sangana Since Neha was 5 and playing ‘spaceship’ with her little brother, she always found astronomy really interesting. She decided pretty early on that she wanted to go into astronomy. As she grew older, theoretical topics in physics also intrigued her. In this issue, to combine these two interests, she centered her stories around astrophysics.
Gustavo Jaramillo Gustavo has a deep interest in astronomy mostly focusing on the unknown depths of the outer universe. Gustavo’s interest of astronomy developed at an early age, after witnessing a total lunar eclipse. Gustavo became intrigued with the change that the moon had presented. This curiosity grew and led to him to take multiple curriculums to advance his mind in astronomy. Overall his main focus is theoretical astronomy.
Michael Taleff Michael’s interest in space started when the New Horizons mission launched in 2006 on a long journey to Pluto. This monumental probe began an interest in space travel and man-made probes and satellites that he never lost. As Michael learned more and more, his interest only grew, eventually becoming part of the Magazine Group to express his interest in astronomy.
Shubhanga Ballal Shubhanga Ballal has always been interested in astronomy and earth science, and believes that exoplanets are the perfect merger of these two worlds. He has wanted to become an aerospace engineer (specifically working on rocket engine design/propulsion) ever since Elon Musk proved that you don’t have to work for an underfunded government agency such as NASA to be a rocket scientist. 4 - parsEc
Space propulsion Story and Art by Michael Taleff
These rocket engines are the vital pieces to man’s dreams to fly to the stars.
Solid Rocket Engines These powerful engines provide early power in a rocket launch. These rockets provide the extra energy a rocket needs to launch into space. Solid Rockets are not ideal in space however because their thrust cannot be cut off once the engine is started. The Space Shuttle Boosters used a combustible compound of Aluminum according to NASA.
Liquid Engines Liquid engines provide a grewat choce for space travel. They can be turned on and off and have their thrust adjusted, an ideal choice for precise rocket burns. Liquid engines usually burn a mixture of two compounds which are brought to a combustion chamber and are ignited, sending the rocket through space. According to NASA, Hydrogen and Oxygen are common fuels.
Nuclear Engines Nuclear rockets are one of the most efficient theoretical rockets out there. They have a series of decaying isotopes which produce heat. This heat excites a liquid, such as liquid Hydrogen, which is expelled out the back. Space agencies have yet to implement this futuristic engines but they are currently in testing.
Ion Engines Ion engines are the most efficient rocket engines in use. They are located on some deep space probes such as Dawn and Rosetta. Ion Engines use electricity to travel by exciting a substance such as Xenon according to NASA. The ESA is currently developing an even more efficient ion engine.
Solar Sails Solar sails are conceptual means of space travel. Large pieces of material capture solar wind and drive the spacecraft forward. To drive a space craft, huge sails are required but this method of travel is extremely efficient.
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Revolutionary flybys and Orbiters Story and Art by Michael Taleff Mission: planck
Launch: May 14, 2009 End Date: October 23, 2013 Distance: Lagrange Point (A point in space where an object stays in the same place relative to two bodies, in this case the Sun and the Earth) Summary: According to the European Space Agency, Planck is an ESA space telescope that observed the Cosmic Ray Microwave Background (CMBR) in an effort to understand the beginning and end of the universe.
Mission: Mars Reconaissance Orbiter
Launch: August 12, 2005 End Date: Ongoing Distance: Mars Orbit Summary: As part of NASA’s fleet of satellites orbiting Mars, NASA describes the Mars Reconaissance Orbiters main goal as searching for evidence for water on the surface. Along with this important research, the satellite will serve as a communication station for future missions.
Mars Reconaissance Orbiter
planck dawn
kepler
Mission: kepler
Launch: March 9, 2007 End Date: Ongoing Distance: Orbiting the Sun Summary: As one of the premier exoplanet telescopes, the Kepler Team has used the transit method of exoplanet search (a method involving measuring the decrease in light output from a star when an object passes in front of it) to discover over 1019 exoplanets. 6 - parsEc
Mission: dawn
Launch: September 27, 2007 End Date: Ongoing Distance: 4,400,000,000 km Summary: As the first space probe to visit a dwarf planet, NASA says Dawn fills a special role in NASA’s space fleet. It is equipped with scientific instruments to study the formation of the solar system by observing the protoplanets Ceres and Vesta.
Although thousands of missions have been launched to explore our enigmatic universe, a few key missions have taught the human race more than others. Through these revolutionary missions, humans understand more about our solar system and universe than ever before. Mission: Galileo
Launch: October 18, 1989 End Date: September 21, 2003 Distance: 4,631,778,000 km Summary: One of the most important missions to Jupiter, Galileo answered many of the questions left behind from Voyager, including extensive studies of Jupiter’s atmosphere and its moons, inlcuding Europa, on which it found a subsurface ocean according to NASA.
Mission: New Horizons
Launch: Janruary 19, 2006 End Date: Ongoing Distance: 5,000,000,000 km Summary: As the first man-made object to visit Pluto, the New Horizons team says the pianosized New Horizons probe contains valuable imstruments to examine this dwarf planet for the first time along with Clyde Tombaugh’s ashes, the discoverer of Pluto.
Galileo New Horizons
Voyager 2 Cassini
Mission: Cassini
Launch: October 15, 1997 End Date: Ongoing Distance: 3,218,688,000 km Summary: As the only spacecraft to orbit Saturn according to NASA, Cassini has discovered much of what is known of the ringed planet. Its trips to the moons and rings of Saturn has taught scientists much of what we know about them.
Mission: Voyager 2
Launch: August 20, 1977 End Date: Ongoing Distance: 7,100,000,000 km Summary: Voyager 2 was lauched to take advantage of a planetary alignment allowing it to visit all of the gas giants in a “Grand Tour”. As the only spacecraft that has visited Neptune and Uranus, it gave scienctists mush of the information that we know about these planets. parsEc- 7
THE ORiGiNS oF ThE UnivERSE By Gustavo Jaramillo
S
cientists estimate that the universe was created about 13.8 billion years ago. Recently the scientific community started to measure the distance between objects in the universe. Scientists compare these distances to those of the past and noticed the distances were getting larger. Through analysis of the data, scientists were able infer that the universe and all of the matter in the universe is expanding. Expansion shapes the universe, but as it happens it could theoretically tear the universe apart. Scientists are left with many theoretical scenarios due to their lack of information about the universe in general. Scientists are able to only predict the ultimate fate of the universe. After the many years that humans have studied space we still do not know the whole behavior of the fabric of space and time. Today, cosmology could potentially provide the answers to these pressing questions. Cosmologists collect information to unlock the mysteries of the universe and shed some light on the universe’s past and future. The most relevant question besides how was the universe created and how the universe will end is what causes the expansion of space? “In 1929, Edwin Hubble discovered that every galaxy was moving away from every other galaxy. This showed that the entire Universe was expanding, meaning everything must have been closer together in the past. His discovery completely revolutionized the way we thought about our place in the Universe”, said Jacob Hummel, a graduate at the University of Texas. For scientists to measure the expansion of space, they observe very bright objects
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such as other galaxies or stars. First scientists compare light from different stars to determine their relative distances, then when a star explodes, the star releases high amounts of light. The light is measured in red shift, which is a measurement of the waves’ expansion. The one main problem for scientists is that the universe is very vast and it is increasingly difficult to take measurements on the outer parts of the universe. The other problem for scientists is that there isn’t enough information collected on the distant past of the universe, but the Planck satellite is helping acquire information in the present. “Data from Planck recently helped us determine that the universe is closer to 13.8 billion years old, rather than 13.7 billion, as we previously thought. The other really interesting thing going on in cosmology right now is the study of what is called Dark Energy,” Hummel said. Dark Energy is a form of energy that allows the universe to expand and accelerates this expansion. Dark Matter is the hypothetical matter that makes up most of the universe. Dark Matter is very hard to detect because it is not reactive to light. Dark Energy and Dark Matter re-
main a mystery even though scientists believe they greatly influence our universe. ”It turns out that roughly 80% of the stuff in the universe isn’t normal matter like what you, me, the Earth, the Sun and every star in every galaxy are made of. Instead, most of the stuff in the Universe is actually composed of what we call Dark Matter,” Hummel said.
“ Da r k E n e r g y a c c e l e ra t e s th e u n i ve r s e a n d m ove s u s fa rth er away a n d re a l ly s e p a ra t e s u s f ro m e a c h o t h e r,“ -Hu m mel “Dark Matter makes up our universe and Dark Energy shapes our universe and together they make up the mysterious phenomenon we call our universe,” said Professor Robert Kirshner, a pro-
Picture Courtesy of NASA Image courtesy of NASA
This is an image of Cassiopeia A , a supernovae remnant in the constellation of Cassiopeia. This image combines different data acquired by the Spitzer , Hubble and Chandra observatories. Supernovae such as these helped scientists discover the acceleration of the universe.
fessor at Harvard University who participated in the development to help discover the universe’s expansion. The most prominent question for scientists is how was the universe created? The most popular theories include the Big Bang and the Big Bounce. The Big Bang states that the universe came from a single point that expanded to become our modern day universe. The Big Bounce theory is similar, but in this version a universe which had previously existed led to the creation of our universe. Hypothetically the pre existing universe had a collapse and from there it started to expand into our modern day universe. Other possible theories hint at the universe being eternal. The universe might be infinite in age and size. For now scientists can rule out Big Bounce it was discovered that the universe’s expansion is accelerating and the collapse of a previous universe would be highly unlikely mainly because Dark Energy overcomes gravity. Luckily, Dark Energy because it is so strong is not affected by gravity and prevents the universe from sinking on itself. While the Big Bounce appears flawed, Big Bang seems increasingly correct,“
The Universe formed in the Big Bang, Technology has definitely moved science in an incomprehensibly massive release closer into the past, but not the beginning. of energy. With so much energy in such In order to get the information that sciena tiny space, it was really hot, but things tist need, there would need to be very imcooled off as the Universe expanded and Imageportant Courtesyadvances. of NASA Kirshner is taking action got bigger. All the matter in the Universe in these new advances. Kirshner is particiwas also created in the Big Bang,” said pating to help build a telescope that is largHummel when questioned in his profes- er than any before here at the University sional opinion about which theory best of Texas.” We are looking to put bigger suited gathered evidence. It appeared instruments in space, even bigger than the that Hummel was not alone in his opin- Hubble telescope. I look forward to seeing ion as Szabo had the same to say.“If you our advancements in our coming decade,” want to know what theory fits the avail- said Kirshner. These new technological able evidence the best, it is the Big Bang advances really allow for a cosmologists Theory,” said Professor Thad Szabo, who to gather the information needed, and currently teaches at Cerritos College in the apart from that really makes a cosmolodepartment of Astronomy. gists job more exciting.. Because cosmology contains so many mysteries the disWith every new invention scientists are covery of something new is very exciting. able to move further into the past and the future. As I previously the Planck Technology may uncover the past, but is Satellite helped uncover the true age of not able to predict the future. Technolthe universe. Older devices had incor- ogy cannot uncover the future because rectly measured the universe’s age. Sci- the universe is too dynamic. The universe entists were missing 100 million years may change unexpectedly at any time and of our universe’s crucial early stages. change the validity of our predictions. “Astronomers have more information from “The Big Bang Theory and our current the past and from that they could make a understanding of particle physics can get prediction but when you are really makus to a time that is 10-43 seconds after The ing a prediction you need to be cautious Big Bang. That’s 0.000...001 seconds, about the future because nothing is yet dewhere there are 42 zeroes between the cided,” said Szabo. For today we can only decimal point and the one,” said Szabo. make predictions at best about tomorrow. parsEC -9
Image courtesy of the Chandra Observatory
Here is a picture of BP Psc, a red giant about 1,000 light years away. It recently consumed a star or nearby planet.
Image courtesy of NASA
Image Courtesy of NASA
The sun is a G-Type main sequence star. As the sun starts to run out of fuel new surprises arise for the human race.
Each prediction is characterized by its conditions. The Big Freeze depicts the universe will end as it expands forever until everything disappears. The Big Freeze is only possible if the universe keeps expanding and does not collapse due to gravity.
then gravity will take over and then the universe will start contracting. From there we will see the universe getting really dense,” Kirshner said. Kirshner believes that the universe will contract itself, but Szabo believes otherwise.
A rivaling theory to the Big Freeze is the Big Crunch. The Big Crunch suggests that the universe will keep expanding and eventually the universe due to gravity or another force will collapse into itself . The Big Crunch is only possible if the universe ceases to expand.
“Evidence points to the Universe being hotter and denser in the past. Thus, as time progresses, it should get colder and less dense.” - Szabo
The Big Rip rivals the Big Freeze and the Big Crunch as the most prominent theory. The Big Rip suggests that the universe will expand forever and create infinite distances between celestial objects. The universe will expand and will rip everything apart including the bonds of atoms till there is nothing. The universe will have to infinitely expand if this were to happen. “There is a possibility that the Dark Energy will be weaker over time and space will stop expanding and do the opposite. The universe will turn around and 10 - parsEc
“The universe will slowly lose the ability to make new stars, meaning that there will be less light as time passes,” Szabo said. Szabo described the basis of what the Big Freeze is and he isn’t the only one to agree with the Big Freeze.
“Well, since the expansion rate is accelerating, everything in the Universe will continue to move farther and farther apart while the stars slowly burn up all their fuel. Once those stars run out of fuel, they’ll die either by exploding as supernovae or turning into white dwarfs stars that slowly cool over many more billions of years. Basically, from here on out, the Universe will get ever more cold and dark, in what’s known as the Big Freeze,” said Hummel. Many people can agree to the Big Freeze because the universe is expanding, and the expansion is accelerating, showing that it overcomes gravity making a collapse unlikely. The universe may not end until a long time has passed. The nearest theory is the Big Rip and could possibly happen in 20 billion years. The universe has only been here 13.8 billion years, and there really should be no worries right now regarding the end of the universe. “More important for us, our Sun will run out of fuel in about 5 billion years and turn into a Red Giant star, which will swallow the Earth and destroy it,” said Hummel. Human kind does not need to worry too much about the universe’s fate. “We don’t know everything and we need to be modest about it because our picture has changed a lot over the years,”said Hummel. As our technology develops and our future presents more new advances cosmologists will find an answer to all our mysteries.
LASA Science Olympiad Explore the World of Science! Learn New Things! Travel the US! Eat Ice Cream! Come to Scio Today!
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lifE aND DEaTH Of a staR By Gustavo Jaramillo
All images Credited to NASA
Nebulas
Protostars are the second step into creating a Sun. Protostars are formed after the collapse of a Nebula. Protostars lack sufficient heat to begin fusion in their core. Protostars can be characterized by their protostellar disks which often affect the rotation of the star. A protostar will move on to the next stage when the core reaches ten million kelvin. A star may never reach the next cycle and some stars take up to ten million years to move on.
Nebulas are the first stage into creating a star. Nebulas are clouds of gas and dust floating in space. One known Nebula is the Eagle Nebula (depicted to the right) in the constellation Serpens. Nebulas move into the next stage of the cycle when a core is formed from pressure created by the collapse of the Nebula.
Protostars
For extra information on Stellar evolution feel free to visit aavso.com, BBC or Universe today. 12 - parsEc
Stars light up the sky and affect our everyday life. Stars are spheres that emit light and are shaped by their own gravity. The Star begins its life after the protostar phase and every star’s future is determined by their mass. The Mass of a star affects the light that is emitted and therefore classified as a different star. The Sun is in its Main Sequence and in the future could affect the existence of humanity as it moves into a Red Giant phase.
Main Sequence Stars
White Dwarfs
The Sun is a main sequence star. A main sequence star produces fusion by changing Hydrogen atoms into Helium atoms. Main Sequence stars are the most common in the Universe making up 90 percent of all stars. These stars can have 1/10 of the mass of the sun and can have up 200x the mass of the sun.
Red Giants
White Dwarfs are very dense and dim stars that burn their very last of their fuel. These Stars will be very common as 94 percent of all stars will reach the White Dwarf Phase. White Dwarfs release light as they burn their fuel. Eventually the White Dwarfs will reach a dark stage where all their energy has been radiated. From there the stars will move into a Black Dwarf phase. A Black Dwarf has never been discovered due to the relatively young age of the universe.
Red Giants are stars that exhaust and burn the helium shells in their core. Red giants have a mass typically under four solar masses. Red Giants are believed to be able to switch into Blue Giants when different helium shells are burned. This phase may last up to one million years depending on their mass. After this stage the Giants can end as Supernovae, but the Sun will transform from a Red Giant into a white dwarf. The Sun still has to wait a couple million years before reaching this stage. The human race may be threatened by the transformation of the Sun. parsEc - 13
blAck HolES
for Beginners By: Neha Sangana
E
verything begins to slow down as objects fall to their destruction. They stretch, bend, break and can never return. “Time stops, space ends, and all the known laws of physics break down in black holes,” said Sarah Salviander, an astrophysicist at UT, “I’m fascinated by mysteries, and black holes are about as mysterious as science gets!” Ever since Karl Schwarzchild defined them using the Theory of General Relativity in 1916, black holes have been the darling of science fiction film and literature. They are no less intriguing in the wild. Black holes currently make up an area of tremendous fascination for astrophysicists. It is a field constantly being modified by new findings. However, the fast-paced research leaves science-fiction outdated. Astrophysicists have discovered many different types of black holes, each with its own theories attempting to describe their formation and activities. Black holes test Einstein’s Theory of General Relativity. This theory basically says mass bends time as well as space.
Courtesy of NASA
Illustration of how a black hole would rip a hole through spacetime due to it’s immense density; rather than just curving it like other celestial objects. 14 - parsEc
Imagine a flat flexible sheet as spacetime. When moving from one point to another on this sheet, one would take the shortest straightest path. If you placed a heavy ball upon this sheet, it would bend the sheet. Now if you tried to travel from one point to another and your path neared the high mass object, you would take a curved path, and it would take longer to travel across the same amount of spacetime. This leads to time moving slowly in proximity to objects of high mass. If you put something extremely dense on this sheet of spacetime, it would rip a hole through the sheet, so that nothing can return. Even light cannot escape this extreme curvature. This is a black hole. “Black holes can serve as cosmic lighthouses that can be detected at large distances. In addition, the energy output from these black holes can have a profound impact in the evolution of the galaxies that are hosting them.” Volker Bromm, professor of astrophysics at UT, explained. Black holes are immense amounts of mass that were previously stars that are condensed into very small areas of space after their explosion if their cores are dense enough. “They are small in
size, you would have such a huge mass packed into the size of our solar system or something like that.” Milos Milosavljevic, professor of astrophysics at UT, said. People commonly misconceive black holes as colossal objects. The idea of black holes, “the most enigmatic objects in the universe,” Salviander said, is so surreal that people idealize them to be large. “Even though they contain a lot of mass, in terms of their diameters, they’re quite small. A black hole with the same mass as the Sun would be less than 2 miles across,” Salviander explained. Black holes also aren’t cosmic vacuum cleaners, nor are they black. One would need to get extremely close to a black hole to be sucked in. “If the Sun were to somehow be replaced with a black hole of the exact same mass, we’d never know the difference; except for the total lack
Courtesy of NASA
Illustration of a supermassive black hole at the center of a galaxy surrounded by an accretion disk which forms as gas and dust is pulled in by gravity.
of sunlight!” Salviander said. Black holes can be orbited very easily as long as one doesn’t go past a certain point,similar to any other cosmic object;for example, if an object got close enough to the sun it would be pulled in by its gravity. You can only orbit a black hole as long as you are farther than a safe distance of three times the radius (this distance only applies to uncharged non-rotating black holes). “If you were within that radius...you would have to keep firing rocket boosters to stay in orbit” Milosavljevic explained, “when you get close to the fictitious surface, it’s called the event horizon of a black hole… you’re going to fall toward the middle and eventually be killed.” As you pass by the event horizon, you might see some distortions around you due to the bending of light. If you pass this safe distance however, you would begin to feel the pull
of the black hole. You will be stretched and squashed in different directions by forces due to the curved spacetime. New findings reveal that information is an important and basic aspect of nature; just like light, energy, and matter. How black holes destroy the information is now one of the biggest questions regarding black holes. “Imagine that you write a message on a piece of paper and throw it into a black hole, after this message goes in…you no longer have access to this message.” Milosavljevic explained. This leads to what is called the “Black Hole Information Paradox”: If information is too important an aspect of nature to be erased, then where is it going?
of radiation that comes off from black holes. This theory predicts the existence of particle-antiparticle pairs near the event horizon that annihilate each other. To someone outside the black hole, it would appear as if the black hole is emitting particles, which is Hawking Radiation. Physicists are still debating over exactly what Hawking Radiation carries and whether or not it is valid . The basic understanding at least, is that the particles emitted by Hawking Radiation do not carry the original information that went into the black hole. “I think it’s an interesting idea, but I’m a bit skeptical, since it’s based on some assumptions that may not be valid, and no one has seen any solid evidence for it.” said Salviander.
By applying quantum mechanics to black holes, Stephen Hawking came up with Hawking Radiation which is a type
Theoretically, due to Hawking Radiation, one can conclude that black holes are slowly radiating particles, losing energy and mass, parsEc - 15
(A)
Courtesy of NASA
(B)
Courtesy of NASA
Image A is an illustration that depicts a “small” black hole about 10 times the mass of the sun in a binary system. Image B is an illustration of one of the most primitive supermassive black holes at the center of a galaxy, qhich dates back 13 billion years and was discovered by NASA’s Spitzer Space Telescope.
and are shrinking. “ The black hole would keep emitting particles until it’s rather light, until it’s maybe you know a fraction of one gram…and then it will just…dissolve into particles. It’s a conjecture.” Milosavljevic explained. This conjecture only applies to smaller black holes, as they emit more energy than they absorb. However larger black holes, which absorb a lot more energy than they emit, are a different story. A supermassive black hole virtually resides at the center of every large galaxy. A strong correlation exists between masses of black holes and the properties of their host galaxies, and this serves as evidence that the galaxy’s formation and evolution is linked. Scientists aren’t sure if the galaxy formed around the black hole or if the black hole formed after the original galaxy formed. “It’s like the chicken or the egg, which came first. Did the galaxies form first, or did black holes form first? If we’re talking about the massive black holes, it’s possible either way,” Milosavljevic said. Some scientists think that the black holes formed first and then kept on growing. Some even believe that black holes stunted galaxy formation, or that the black holes blew away matter from 16 - parsEc
the centers of galaxies and stopped their growth. “The physical connection between the two remains elusive,” Salviander said. Supermassive black holes have existed since around 800 million years after the Big Bang. How these gargantuan objects grew so quickly remains a mystery. Originally, people thought that this process could be very simple. People thought you could start with the relic of a dead massive star of 10 solar masses and then the black hole could grow by accreting material in its surrounding. However, the problem with this idea is that accretion takes a long time; too long to accrete material fast enough. The theory of direct collapse black holes, suggested by Volker Bromm at UT and Avi Loeb at Harvard, offers the idea that you start with a huge cloud of about a million star masses of primordial material, and in conditions where this cloud cannot cool much, it would be possible for a supermassive black hole to form. “It would just collapse into the center of a dark matter halo,” Bromm explained. Eventually it would reach conditions where relativistic instabilities kick in, “leading to the formation of a seed black hole
that already starts with, say, one hundred thousand solar masses,” said Bromm. Astrophysicists find these cosmic lighthouses not by observing them directly, but by observing the impact they have on their surroundings. Stellar mass black holes, 10 to 124 times as massive as the sun, lead solitary lives and are difficult to detect. Scientists detect these when a star passes close enough to the black hole to emit x-rays as it is pulled in. On the other end of the black hole spectrum, supermassive black holes are detected by scientists through observations of their impact on nearby stars. Many scientists observe the nearest supermassive black hole, the one at the center of the Milky Way, to learn more about the behaviors of supermassive black holes. “It’s the closest massive black hole that we know of, and astronomers are measuring how stars are orbiting this black hole. You can have stars that go in ten years around the black hole at very large velocities, and they’re also observing how clouds of gas are orbiting the black hole,” Milosavljevic explained. New findings on this black hole pop up everyday, though they may not all be significant. If there are supermassive black holes, and there are small star mass black holes, then theoretically there should be intermediate sized black holes as well. However, “We don’t know of any kind of law of physics or a reason why there shouldn’t be intermediate mass black holes,” Milosavljevic said. Though scientists have found evidence for medium sized black holes in the cores of globular clusterstight groupings of old stars orbiting the halos of a galaxy-intermediate sized black holes themselves have yet to be found. Intermediate sized black holes are too big to have a companion star (a binary system of a black hole and a star), which many small black holes have, and are too small to settle in the middle of galaxies like supermassive black holes. This presents an obstacle in finding these objects. “I think there’s a good chance they exist, based on the evidence,” said Salviander. For now, nothing about black holes is set in stone. Future research could potentially inflict a great change in our views on them and completely answer the numerous gaping questions regarding them.
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Courtesy of Timothy Boocock parsEc - 17
WHiTE holEs And WorMHolES Story and Art by Neha Sangana
It is known for sure that black holes exist, but what about white holes and wormholes? The other two theoretical objects in this area of astrophysics have yet to be found, or even accepted as valid. There are many problems with each theory, as well as numerous reasons why they could exist; but just because they could exist does it mean that they do? A white hole is essentially the opposite of a black hole. It is a hypothetical region of spacetime that cannot be entered from the outside, but matter and light can escape from it. EVIDENCE FOR
Black Hole Event Horizon Singularity
Event Horizon
White Hole
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-- General relativity’s equations suggest that an object falling into a spinning black hole could fall through a wormhole (the rotation would smear the singularity into a ring) and emerge from a white hole in a different region of spacetime. -- White holes would solve the “black hole information paradox”, as the information lost in a black hole would be recovered in a white hole. -- By applying loop quantum gravity, theorists Hal Haggard and Carlo Rovelli of AixMarseille University showed how a white hole could form.
EVIDENCE AGAINST -- Mathematical solutions are unrealistic because they describe a universe that “contain only black holes, white holes, and wormholes”, astrophysicist Andrew Hamilton told Maggie Mckee from NOVA. -- Wormholes have yet to be found and are too unstable. -- According to an article on Nautilus published in 2014 by Matthew Francis, white holes require something like a “gravitational sewer explosion”. -- Following the mathematical model that physicists use, one can never have a situation where a white hole exists at the same time as anything else.
EVIDENCE FOR Wormholes, which are hypothetical bridges through spacetime that create a shortcut that reduces travel distance, were theorized by Einstein and Nathan Rosen in 1935.
-- According to Space.com, certain solutions of general relativity allow wormholes where each mouth is a black hole. -- New research suggests the possiblility of both ends of wormholes being connected by quantum entanglement.
EVIDENCE AGAINST -- None have been discovered. -- Though there are theories, we can’t discern exactly how they connect two points in spacetime. -- Nobody has any idea how wormholes could be created.
TRAVEL BY WORMHOLE Pros -- Certain solutions of general relativity allow for the existence of wormholes where each mouth is a black hole. -- Exotic matter, which contains negative energy density and large negative pressure, could keep a wormhole open and unchanging for longer periods of time.
Cons -- Size is the first problem; primordial wormholes are predicted to exist on microscopic levels. -- Wormholes are very unstable and collapse quickly for travel. -- Even if wormholes were found, technology that we currently have is not advanced enough to enlarge or stabilize them. parsEc - 19
EXohunt: thE SEARCH foR ANother EARTH By Shubhanga Ballal
HD 189733b, the closest Hot Jupiter to Earth
Courtesy of NASA
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watery world two times the size of Earth orbits a bright and fiery F-type star. It is not too close to its sun where all of the water would evaporate, leaving its surface baked dry by the searing heat. It is not too far away, where the oceans would freeze into an inhospitable winter wonderland. Looking closer, a vibrant blue ocean comes into view, with giant waves endlessly circling the planet. This seems like a dead giveaway for life...doesn’t it? “Some people think that a planet completely covered with water would have no life. [They] believe that you have to have land to concentrate those molecules to form life...if you only have oceans all the chemicals would get diluted.” says Sara Seager, professor of physics and planetary sciences at MIT. All over the world, planetary scientists, biologists and astronomers hotly debate this topic and many others. Exoplanet science, the study of planets outside of our solar system, is the hottest topic in astronomy, evidenced by the recent development of exoplanet finding satellites by NASA. The motivation for this frenzied search: the hope of finding extraterrestrial life. Professor Seager also believes that keeping our country ahead of the competition in terms of technological innovation motivates scientists. Whatever the reason, it seems that this branch of science comes out with discoveries at a very prolific rate. As G. Fritz Benedict, a research scientist at the University of Texas, puts eloquently,”All of astronomy is a search for extraterrestrial life.” Transit technique, the most successful exoplanet finding method, has found the most exoplanets. In this method, as-
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tronomers analyze the light curves of the star to determine if an exoplanet orbits it. When the exoplanet crosses, or transits, the star, it causes a dip in the light curve. Of course, this dip will be very small and is very hard to detect, so the majority of planets detected are large planets orbiting very close to their stars. In addition, the planet’s transit has to be perfectly aligned to be viewable from Earth. This technique can give us the size of the planet, provided that we know the characteristics of its star. The second most common and effective method, based on the number of planets detected, is the radial velocity method. Contrary to popular belief, the Earth does not orbit around the sun. Instead, they both orbit around a common center of mass, called the barycenter. Most of the time, the star moves very little because the barycenter sits inside it. However, this movement, however slight is still detectable. When the star moves away from us, its light becomes redshifted due to the doppler effect. Similarly, the light becomes blueshifted when the star moves towards us. By examining the spectra and finding the magnitude of the blueshifts and redshifts, astronomers can determine the location of the barycenter. From there, a bit math will give
us the mass of the planet. Combining this information with size estimates from the transit technique and atmospheric observations, astronomers can get a very good picture of the characteristics of the planet. Other exoplanet finding techniques are not used very commonly. For example, astronomers sometimes use direct imaging to find exoplanets. With this method, powerful cameras are used to get a picture of the exoplanet. Because stars are so bright, its light far exceeds the tiny amount of light that the exoplanet reflects. The greatest challenge for astronomers is to block out all of the starlight so that we can view the exoplanet. High resolution images taken using this technique only show the planets as small specks of light. The only exoplanet system found using this technique is HR 8799. The other technique sometimes used to find exoplanets is astrometry. It is similar to the radial velocity method in that they both use the revolution of the star around the barycenter. While radial velocity techniques use the redshifts and blueshifts of the star’s light, astrometry uses cameras to see the star change position in the night sky. Even with all of these contenders, it is undebatable who is king of the exoplanet-finding hill.
“The transit method [is the most effective], primarily because there is a space telescope called Kepler that has been working for over 4 years now, and it has by far found more exoplanets than any other approach,” Benedict says. Although the above techniques are often used to find planets, they are not used to find the characteristics of the planet. Astronomers use a novel technique, Doppler Tomography (also known as DT), to fill that gap. Astronomers don’t use DT to find exoplanets, but rather use it to investigate potential planets already tagged by another technique. All stars rotate to some degree, so astronomers can use the doppler effect to determine the qualities of the planet; astronomers refer to this as DT. Because stars rotate, the side rotating towards us will be blueshifted and the side rotating away will be redshifted. By analyzing how transiting planets dim the light of the star, astronomers can get valuable information about the planet’s orbit. More specifically, they get the spinorbit misalignment of the star, which tells them whether the planet orbits in the same direction as the star rotates, in the opposite direction, or if it orbits over the star’s poles. This information helps astronomers refine their planet formation theories that detail how the planets got so close to their stars.“You can get a lot more information from doppler tomography. Or rather, you would get a different set of data,” says Marshall Johnson, a graduate student at UT.
“Venus and Earth, they are both the same size. If we were looking at a system and we saw a venus and an earth we wouldn’t know that one is completely inhospitable and one is beautiful, with oceans, continents and sunny tropical islands,” Seager said. Even with the myriad of techniques that exist, astronomers still face some technological challenges in finding these exoplanets. According to Seager, a lot of the problems regarding exoplanet detection stem from the discrepancy between the starlight and light reflected from the planet. In contrast, Benedict states that the problem does not stem from too much starlight, but rather the lack of it. To get light from distant stars, astronomers need big telescopes that can reach astronomical costs. In addition, ground telescopes can suffer from distortions caused by turbulence in the atmosphere and the mirror sagging under its own weight. Although technologies such as active optics and adaptive optics can minimize these distortions, they cannot completely eliminate them. According to Benedict, astronomers would need to send the telescopes into space, where there is no atmosphere or gravity to cause distortions. “You would like to be above the atmosphere, so the real question is how to launch a big mirror into space when launch costs are $1000/lb,” Benedict said.
James Webb Space Telescope, which will be used by astronomers to find exoplanets Courtesy of NASA
Looking to remedy these technological issues are the next generation of ground telescopes such as the Giant Magellan Telescope, a segmented mirror telescope with a diameter of 24.5 meters and a total collecting area of 368 square meters. Astronomers plan to complete the telescope by 2020. The telescope’s high resolving power, or ability to distinguish fine detail, will allow it to produce images 10 times sharper than the Hubble Space Telescope. Astronomers will locate it high in the Andes mountains, where atmospheric turbulence or moisture cannot interfere with operations. Outfitted with state-ofthe-art spectrometers, the GMT will observe and determine the properties of several exoplanet atmospheres. Its large collecting area will also make it possible to directly image several exoplanet systems, and it will use the radial velocity technique to find Earthlike exoplanets. “These telescopes can tell us about the atmospheres of these planets. For earth sized planets, you would like to know, does it have oxygen, can it support life?” Benedict said. The Transiting Exoplanet Survey Satellite, or TESS, as it is known, will soon revolutionize planet hunting starting in 2017. Unlike its predecessor, Kepler, TESS will find transiting exoplanets around bright stars where follow-up observations are easy to make. According to NASA, TESS will monitor over 500,000 stars for transiting exoplanets during its two year mission. The focus of the mission will be on Earthlike planets around Sunlike stars. Astronomers must prepare for a tsunami of data because “TESS will find every transiting planet with a period of a week,” Johnson said. Although TESS is the perfect satellite for finding exoplanets, it needs a little help to analyze them. Thankfully, the James Webb Space Telescope, or JWST, will parsEc - 21
planet because in the big picture, there are very few things that we can learn remotely about exoplanets. Almost nothing, really,” Seager said.
Potentially Habitable Planets discovered as of April 2015
be the perfect partner. Starting October 2018, JWST will conduct follow up observations based on data from TESS. JWST’s extraordinary capabilities will allow it to analyze exoplanet atmospheres in detail and determine the habitability of the planet. Although yet to be finalized by NASA, the JWST mission could be paired with another mission, called New Horizons, that would build a large starshade that would sit in front of the JWST and block out starlight, making observations and direct imaging easier.“JWST will help us make those follow up observations because it has a lot of capabilities in the IR portion of the spectrum where some very interesting things come up. For example, water, CO2 and oxygen have spectral imprints in the IR,” Johnson said. With all of the satellites and telescopes out there, when will we find an earthlike planet with a strong probability of having life? Astronomers believe that between 5 and 20 percent of sunlike stars have an earthlike planet. Seager believes that Earthlike planets do exist, because water is an extremely common planetary material that is found on asteroids, comets and everything in between. Even if we find and earth-sized planet around a sunlike star, we have no way of knowing right now that the planet is habitable. “Venus and Earth, they are both the same size. If we were looking at a system and we saw a venus and an earth we wouldn’t know that one is completely inhospitable and one is beautiful, with oceans, continents and sunny tropical islands,” Seager said. Even with these technological restrictions, Benedict remains optimistic and believes that we can find an earthlike planet within 20 years. Understandably, it’s hard to determine the qualities of a tiny planet millions of light years away. With the help of conventional 22 - parsEc
Courtesy of PHL @ UPR Aricebo
methods, astronomers can determine the size and mass of the planet. These methods, unfortunately, are limited in what they can do in determining the existence of life in exoplanets. By looking at the atmosphere of the planet, though, astronomers can determine several important sets of data. “We have a couple of ways that we think we might be able to find life but really, the best bet is to look for gases in an atmosphere, and then figure out if those gases could be produced by life or not.” Seager explained. When starlight filters through an exoplanet atmosphere, it excites the molecules in the atmosphere. By analyzing the spectra of the exoplanet’s atmosphere, astronomers can find its composition by looking at the absorption lines of the atmosphere. Although it may seem like magical mumbo jumbo when they determine the atmospheric composition of a planet unimaginably far away, but people have made spectroscopic observations of other astronomical objects ranging from stars to galaxies to other planets in our own solar system with a very high level of confidence. The only difference: astronomers measuring things so very tiny compared to other objects that they have observed. “We want to detect gases on an exo-
“...people have studied astronomical objects at great distances using spectra. And that is something that people have done for so long,” Seager said.
Atmospheric observations tie directly to the quest to find extraterrestrial life in the universe. Living organisms exclusively produce gases such as oxygen and methane. These gases act like flashing beacons to astrobiologists.But some species, like us, don’t produce measurable amounts of methane and we don’t produce any oxygen. “And the reason we don’t know is the planet has to have life and that life has to actually emit a gas that we can detect. But humans, we emit a gas, we breathe out carbon dioxide, but our atmosphere already has carbon dioxide, so that wouldn’t be helpful. So there are a lot of subtleties involved,” Seager said. Spectra are powerful pieces of information that are used in many fields of astronomy. To find the qualities of an atmosphere, astronomers use two different types of spectroscopy. First, astronomers analyze the star’s light using emission spectroscopy, which they use to determine the composition of the star. Certain lines appearing on the emission spectrum can signify the presence of certain elements, as well as the age and type of star. Then, they use absorption spectroscopy to find the composition of the atmosphere. Certain elements in the atmosphere in the planet will absorb the light of the star, and astronomers use these discrepancies to tell the composition of the atmosphere. “...people have studied astronomical objects at great distances using spectra. And that is something that people have done for so long,” Seager said. Thanks to Seager’s research, astronomers can estimate the number of these habitable planets of the galaxy. The “Seager Equation”, a spinoff of the Drake Equation, provides a framework for astronomers to estimate how many of these planets in the habitable zone could have life based on atmospheric observations. According to Seager, while some of the terms cannot be determined right now, it is still a valuable tool. “I thought it would be actually helpful to help communicate to people that we actually are doing a quantitative search for life out there.”
International Space Station Story and Art by Michael Taleff The ISS has been the Earth’s representative in space for over 15 years. It’s numerous modules have constantly discovered new properties of objects in space. As a home for multiple nationalities of astronauts at a time, it not only serves as a scientific presence, but a symbol of peace and international collaboration.
Zarya Zvedza Weight: 18,051 kg Launch Date: 7/12/2000 Zvedza is a Russian storage module that is attached to the end of the ISS. It has a pressurized section which can support six Russian cosmonauts and an unpressurized section. Zvedza contains the ISS computers.
Weight: 19,323 kg Launch Date: 11/20/1998 Zarya was the first piece of the International Space Station to be launched according to NASA. It was fitted with enough electronics and pieces to sustain itself. Zarya is fitted with three docking nodes, one of which connected to the first US module, Unity. Zarya contains two large solar arrays which were later retracted with the installation of more modules.
kibo Weight: 24,286 kg Launch Date: 3/12/2007
destiny Weight: 14,520 kg Launch Date: 2/7/2001 Destiny is the United States research module according to NASA. Destiny contains a very high quality wind to observe the Earth as it passes underneath. Destiny contains some racks for experiments along with full life support functionality.
Kibo is the Japanese laboratory module. Kibo contains an area for experiments that is pressurized. Kibo also contains a platform that is exposed to space. A robotic arm transfers experiments to the outdoor facility. Kibo holds the title as the largest module on the ISS.
Columbus Weight: 12,800 kg Launch Date: 2/7/2008 Columbus is the largest European Space Agency laboratory module according to NASA. This module fits ten racks of experiments. Columbus has three pieces of equipment attached on the outside including a solar observatory. parsEc - 23
deep SpAcE Industries By: Shubhanga Ballal
D
eep Space Industries is one of the few companies that is exploring the field of asteroid mining, along with Planetary Resources and a few others. This infographic explains their plans for the future as well as the company’s mission. DSI plans to extract resources from asteroids such as precious metals (for sale on Earth markets) and fuel (for use on future space missions).
firEflY
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his spacecraft, callled the firefly, is only 15 cm by 30 cm, but it is perhaps the most important spacecraft for collecting data on asteroids. The firefly will use various sensors such as spectrographs to relay quantitative information about the asteroid to scientists on Earth. This information can be used to determine which asteroids are the best candidates for initial harvesting missions. The low cost of this probe allows it to be released in large numbers to investigate several steroids.
FireFly: 2015-2018
DragonFly: 2023-2025
all information obtained from: http://deepspaceindustries.com
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2020
HArVESTOR
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Asteroid Courtesy of NASA
Other Art Courtesy of Brian VersteegA
his design is called the harvestor. Although in a highly conceptual stage right now, it is one of the plans to create a spacecraft that can “tow” an asteroid to an orbit where it can be processed. Decisions still need to be made to determine where the asteroids would be located in order to ensure that no asteroids fall down to Earth.
drAGONflY
T
his concept, called the dragonfly, is one of the designs for a harvestor. These harvestors will collect loose rocks and regolith (soil) from the asteroid’s surface and bring it back to orbit near Earth. The harvestor will collect anywhere between 10 and 600 tons of material. 50 kg of the material will be collected for testing, but the remainder will be used for commercial activities.
Harvestor: ???
2030
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ThE kEy to us: ExtratErrEstrial icE By: Michael Taleff
A
pproximately 36 years ago, Voyager 1 flew by Jupiter’s satellite, Europa as it imaged a series of distinct lines and ridges on the surface. As scientists examined the photos, they could find no topographic profile. These ridges appeared so flat that they were described as “painted on by a felt tipped marker.” This discovery, confirmed by Voyager 2 in July 1979, spurred scientists to study ice, learning more about it than they ever had before.
Ever since the Voyager program imaged the satellites of the outer planets, scientists have been researching and studying the diversity of ice in our solar system. Ice comes in different crystal structures that form under the extreme conditions of the various moons in our solar system. Its dynamics form structures that are unique and intriguing to scientists. This diversity is exemplified through the mysterious chaos terrain on Europa; the blue Tiger Stripes on Enceladus and the cantaloupe terrain on Triton. Discoveries in this field can help scientists understand the apparent abundance of water on Earth, an anomaly among the inner planets. An abundance of future missions are being planned to explore the possibility of life on icy bodies such as Europa and Enceladus. As scientists study ice further, their understanding of the formation of the solar system and even our home, Earth, become clear.
study chaotic terrain we’ll know how the ice is and how thick the ice is, and find whether there’s life under the surface” said Professor Richard Greenberg , a member of the Lunar and Planetary Lab and Department of Planetary Sciences at the University of Arizona. Fully understanding these features allows scientists to build an accurate model of surface conditions
Covering the surface of Europa’s icy crust is a series of icy convulsions, heaps of contorted ice with no apparent pattern. Scientists have dubbed these formations “chaos terrain,” an apt title. Chaos Terrain appears as large rafts of ice, scattered in a field of newly formed, disorganized ice. Chaos Terrain varies in size from the one kilometer in diameter to over 1000 kilometers in diameter. They are scattered all over the pristine surface of Europa, disrupting the formations that are already present. “If we
which can be useful in creating hypotheses on the likelihood of life under the surface. The cause of chaos terrain is still unknown, but scientists have modeled some competing theories for the development of Chaos Terrain to discover the factors behind its formation. Two competing theories on the cause of chaos terrain are melt-through and brine-mobilization. The brine-mobilization model requires the presence of salt which causes sections of the Europa crust to melt and refreeze. This can explain
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“If we study chaotic terrain we’ll know how the ice is and how thick the ice is, and find whether there’s life under the surface” -Greenberg
the plates of ice and newly reformed ice characteristic of chaos terrain. The meltthrough model requires the fracturing of the ice crust into rafts of ice. Water from the subsurface ocean rises and freezes the plates back together. An analogue for the melt-through model can be observed at the Earth’s poles where pack ice melts and refreezes. “[The plates of ice] can freeze back in place when winter comes and gets colder… it looks just like chaotic terrain,” said Greenberg. Although scientists have these theories, until a probe is sent to Europa, the cause of chaos terrain will remain unknown. “It would be to better understand the topography, [different] places would be high and low depending on which of those processes were responsible for forming chaotic terrain,” said Greenberg. This topographic information would have to be found before the debate about the chaos terrain can be resolved. Crisscrossing the surface of the cold Europan crust are a series of cracks in the crust called linae. Their presence indicates the movement of Europa’s crust. Europa’s crust, like Earth is split into plates. As the boundaries of the plates, fresh water from below rises and freezes in a characteristic ridge. When the plates move apart again, the ridge is split in half, creating a double ridge on top of the break in the crust. This ridges are constantly created on the ever changing crust on Europa. They can grow
into multiple ridges, miles across. Over the hundreds of millions of years that Europa has existed, these ridges scar the surface of Europa, giving it the recognizable criss cross pattern that humans know today. “Connections between the surface and the oceans could be important to determine whether there could possibly be life down there in the ocean and studying things like the cracks and the chaotic terrain can tell us whether the ocean is connected to the surface,” said Greenberg. These Europan formations are primarily caused by a single phenomenon, tidal forces. As Europa travels around Jupiter, the gravity of Jupiter pulls on Europa. “As it goes around in its concentric orbit, the thing will get stressed and unstressed, it’ll constantly be worked,” said Greenberg. This tidal force exerts pressure on Europa, cracking the surface. This tidal force, through factors such as friction, produces heat. “That warmth is enough to melt [the ice],” said Professor Chas Miller, a professor of Astronomy at New Mexico State University who is interested in the icy bodies of the solar system. The liquid ocean and the tidal force acting on Europa can
explain many of the formations visible on the Europan surface. These formations can tell people more about Europa itself, allowing us to properly form conclusions about the processes that occur on it. This
“The idea is that perhaps these breaks in the surface are because of that tidal force they’re pulling it apart a little bit on one part of the orbit and then they close on the other” -Miller can lead to conclusions about the possibility of life under the Europan crust. Although Europa is one of the most well known examples of a possible home of
alien life, there is a less well known candidate, Enceladus. Enceladus, the sixthlargest moon of Saturn, is like Europa, because it is extremely dynamic, even for its small size. Near the south pole of the moon are scars in the surface that portray the forces working on Enceladus, Tiger Stripes. The Tiger Stripes are a series of parallel lines that appear bluish in color. Tidal flexing causes these formations like the linae on Europa. “The idea is that perhaps these breaks in the surface are because of that tidal force they’re pulling it apart a little bit on one part of the orbit and then they close on the other,” said Miller. As Enceladus orbits around Saturn, the tidal forces acting on the moon create these cracks. When the planet is stretched by the tidal forces, the cracks rub together, giving the area a higher heat signature than the rest of the area. The Tiger Stripes are home to plumes miles high that emanate from the area. This phenomenon caused scientists to examine this area in detail. The Cassini program visited Enceladus and found that these plumes were made of water vapor and that they are the source of the E-Ring of Saturn, the second outermost ring of the planet. Later
Courtesy of the NASA Galileo Spacecraft
Courtesy of the NASA Cassini Spacecraft
Courtesy of the NASA Galileo Spacecraft
Left: A photo of the moon Enceladus featuring blue Tiger Stripes in the southern portion of the moon; Above Right: A photo of Europa showing the extensive cracks, or linea, in its crust; Bottom Right: An example of chaotic terrain on Europa, the Conamara Chaos. parsEc - 27
observations suggested a liquid ocean under the Tiger Stripes, making Enceladus another planet with the potential for life. Enceladus is also home to volcanism, but not the volcanism seen on Earth. The cold temperatures on Enceladus provides an environment where water is analogous to lava and structures of ice are analogous to volcanoes. These cryovolcanoes and cryomagamas are common on Enceladus where there are relatively few impact craters. “The lack of craters at the south pole of Enceladus is probably due to a combination of them being erased by tectonic activity and cryovolcanic eruptions (where water is the lava instead of rock), perhaps they are even buried by the equivalent of ash deposits from the erupting plumes” says Professor Prockter, a professor and researcher at the Johns Hopkins Applied Physics Laboratory. Tidal forces caused by orbiting Saturn causes friction in the crust, enough friction to heat ice into a liquid, even on an extremely cold body such as Enceladus. As Enceladus orbits Saturn, cryovolcanoes erupt and cover the surface with liquid water. This water freezes and hardens, forming a brand new coat of ice on the moon, like a zamboni smoothing out an ice rink. This leaves the surface of Enceladus pristine and unmarked. Triton is the biggest moon of Neptune, comprising most of the combined mass of Neptune’s moons. Its origins are mysterious but most scientists believe that it started its life as a Kuiper Belt object, much like Pluto. Triton was later captured, explaining its strange orbit shape and its orbit in the opposite direction of most moons, a retrograde orbit. Triton’s only images were from Voyager 2 but those images revealed a lot about the surface. Since scientists have theories of its origins, new advances can be made that describe most Kuiper Belt objects by either studying Triton or Pluto, another Kuiper Belt Object. Triton is also home to cryovolcanoes much like the ones found on Enceladus. Triton’s skewed orbit creates a lot of heat from the tidal forces on the moon. “Liquid water would be something pretty hot compared to the surface of the really cold moon,” Professor Miller explained, creating an ample environment for cryomagmas. These cryomagmas behave much like the cryomagmas on Enceladus. Tri28 - parsEc
Courtesy of the NASA Voyager 2 Spacecraft
One of the only existing pictures of Triton taken by Voyager 2 with Cantaloupe Terrain pictured in the north along with cryovolcanic eruptions that are noticeable as the dark smudges.
ton also is home to cryvolcanic plumes that shoot nitrogen into its small atmosphere. These plumes are much like those emitted by Enceladus. These mile high plumes can be seen in Voyager 2’s pictures of Triton. Triton, although visited by a flyby probe, is still not completely understood. Triton is home to cantaloupe terrain which looks much like the skin of a cantaloupe, with grooves and cut interspersed in the crust. Although there are some theories as to its formation, scientists still do not know much about it. “I don’t know what causes the cantaloupe terrain exactly, I don’t think anyone does at this point yet,” Professor Miller said. This is only one of many mys-
“Lots of things in this outer solar system that have ice on the surface turn pink or red and Triton is a pinkish color” -Miller teries on Triton, another one being its ice. Triton’s ice is most likely made of frozen Nitrogen from its atmosphere. Triton’s ice is also probably home to different compounds due to its color. “Lots of things in this outer solar system that have ice on the surface turn pink or red and Triton is a pinkish color,” Professor Miller explained. Ice in the outer solar system is still not well understood and it is hard to create labora-
tory conditions to test hypotheses. Scientists will have to find samples of the ice and test them to find the cause of this coloration. Scientists hope to find some answers when the spacecraft New Horizons reaches Pluto in the summer of 2015 because of the similar origins of Pluto and Triton. Ice research is still going on today, through the numerous probes that NASA has sent into the solar system. Cassini and Galileo’s extensive work at Saturn and Jupiter allowed scientists to view the moon like they never have before. New Horizons, the first probe to travel to Pluto will examine the surface features and makeup, furthering scientist’s understanding of outer solar system ice dynamics. NASA also has a concept mission, Europa Clipper, which will map and study Europa in the near future. Although there are these missions, many moons and planets will remain unvisited. “They only flew by something like this once. And it’s the only place they’ve seen it and we can make guesses but it’s really hard to prove some of them and that’s why when we fly by something once, it’s always tempting to want to go back, but of course we don’t have the money to send things to every place that we want to go,” Professor Miller said. By studying ice, scientists can piece together the origin and formation of the solar system. “And just in general, people will want to know how did our solar system really form and a key clue is where the ice is and how the ice is throughout the solar system where we’re looking at it after it formed over 4 and a half billion years ago” Professor Miller said.
Do you enjoy engineering? Come to Ms. Earnheart’s room every other Thursday for
LAsa ENGINEERING CLUB
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SomE VErY QuEstionAblE AstRonomy JokEs By: Shubhanga Ballal
A seminar on time travel will be held last Tuesday. How many balls of string would it take to reach the moon? One. A very large one. Black holes are most commonly found in black socks. Why didn’t the Dog Star laugh at the joke? It was too Sirius. Astronomers say the universe is finite, which is a comforting thought for those people who can’t remember where they leave things. 30 - parsEc
How many astronomers does it take to change a light bulb? None! Astronomers aren’t afraid of the dark. How far can you see on a clear day? 93 Million miles...From here to the Sun. “Twinkle twinkle little star....” Crap! Lousy seeing again. Heisenberg is out for a drive when he’s stopped for speeding. The policeman says “Do you know how fast you were going?” Heisenberg says “No, but I know where I am.” “There’s just one thing I can promise you about the outer space program – your tax dollar will go further.” — Wernher von Braun please pretend to laugh at at least onE of them parsEc - 31