The Appulse Vol. 49 No. 91

OFFICIAL PUBLICATION OF THE PHILIPPINE ASTRONOMICAL SOCIETY

T he

APPULSE

PROPELLING ASTRONOMY EDUCATION TOWARD THE ACHIEVEMENT OF SCIENTIFIC EXCELLENCE AMONG FILIPINOS

VOL.49 NO.91

photo by: Kashogi Astapan

SUPERMOON

shutter speed: 1/120 iso 1600 Camera and telescope: fuji xe2 mounted on c90 mak celestron telescope

2016

The Year 2016 in Space News

Near-Missed Adventures with Luna’s Mesmerizing Face

Geminids 2016: Stargazing at the Big Handy’s Grounds

Photo By: Kashogi Astapan Camera: Fuji XE2 (1/120 ISO 1600) Telescope: C90 Mak Celestron

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The Year

2016 in Space News By: Pecier C. Decierdo Science Education Officer The Mind Museum

Marking the change in the year is, in a way, an astronomical observance. Like celebrating a birthday, it is a way of recognizing that we have once again made a complete circuit around the Sun aboard planet Earth.

NEWS facilities, they would fire lasers at 90-degree angles down a 4-km long tunnel. At the end of the tunnel is a mirror that reflects the laser back. If there is even a very slight change in the length of one tunnel due to the passage of a gravitational wave, this will cause interference between the two incoming laser beams.

After multiple successful runs in 2015, scientists found signals that suggested they have detected gravitational waves. They wanted to make sure, so they kept their results secret while they analyze if indeed they have detected gravitational waves. After careful analysis, the scientists at LIGO finally announced their discovery early this year.

This detection marks a new era in astronomy.

Before this year everything we know about deep space came to us through electromagnetic waves or cosmic particles. Visible light is an example of electromagnetic waves. The detection of gravitational waves is not just further confirmation of Einstein’s general relativity it also opens up a new way of exploring the universe. Now it is possible to learn about astronomical objects by detecting the gravitational waves they radiate our way.

Astronomy will never be the same again after this.

With that said, I hope you enjoy my picks to represent the year 2016 in space news.

Not long after it was launched, Diwata-1 did not disappoint. It beamed back images of the Earth’s surface that were considered world-best quality.

PASBOARD

A hundred years after Einstein published the theory of general relativity, scientists working at the Laser Interferometer Gravitational-Wave Observatory (LIGO) finally detect gravitational waves directly.

This detection represents our entry into a new era of astronomy.

OF Gravitational waves confirmed. Image credit: LIGO

THE PHILIPPINES’ FIRST MICROSATELLITE, DIWATA-1, STARTS ORBITING EARTH

DIRECTORS Chairman of the Board

Engr. Camilo Dacanay President

Leah Villalon Vice President

Hernan Dizon Secretary

Arthel Gavino

Before the detection this year and late last year, the other evidence for the existence of gravitational waves was indirect. Astronomers Russell Hulse and Joe Taylor observed the dance made by a binary system where one star was a pulsar. Because pulsars can act as cosmic clocks, that made it possible to measure time as experienced by the stars in the Hulse-Taylor system. They found out that the system was losing gravitational energy. This means that they radiated gravitational energy, and this can happen only if they emitted gravitational waves.

LIGO was specially designed by engineers and scientists to detect these very, very tiny changes in the shape of spacetime. At each of the two LIGO

Diwata-1 was handed over to JAXA early this year for launch preparations. It was taken aboard a rocket whose payload docked with the International Space Station (ISS). Diwata-1 was released into orbit from the Japan Experimental Module of the ISS in April of this year. It is expected to orbit the Earth from an altitude of 400 km for 20 months.

A second microsatellite is scheduled to orbit starting next year. Many fans of space exploration hope these are just the first steps in a long journey into a full-fledged Philippine space program.

SCIENTISTS AT LIGO ANNOUNCE THE FIRST DIRECT DETECTION OF GRAVITATIONAL WAVES

Gravitational waves, however, are very difficult to detect directly. These ripples in space and time are typically the size of an atom or smaller.

The 50-kg Diwata-1 is the first microsatellite owned by the Philippine government. It was co-developed by teams of engineers and scientists from the Department of Science and Technology (DOST), the University of the Philippines (UP), Hokkaido University, and Tohoku University. The project of making Diwata-1 and sending it to orbit is a result of collaboration between the Philippine government and the Japan Aerospace Exploration Agency (JAXA).

One of the objectives of sending Diwata-1 to space is to help scientists on the ground monitor the Philippine’s natural resources as well as provide data that can lead to better disaster risk reduction and management. The microsatellite is equipped with a High Precision Telescope (HPT) that can help scientists assess the damage caused by natural disasters such as typhoons and volcanic explosions. It can also help researchers monitor changes in cultural and natural heritage sites.

Below is my list for the top 10 space news of 2016. There is an element of subjectivity in choosing them. Like all top 10 lists mine will be missing news that others will consider more groundbreaking or interesting.

General relativity is Einstein’s theory of gravity. One of its many predictions is the existence of gravitational waves, which are ripples in spacetime.

General relativity predicts that two very massive objects spiraling into each other can produce these spacetime ripples. While all other predictions were confirmed in the past century, gravitational waves have eluded our detection.

The year 2016 is a milestone in the Philippines’ goal to have a space program. This year Diwata-1, the country’s first microsatellite, started orbiting the Earth and beaming back pictures it has taken of the planet.

Assistant Secretary

Jeffre Blanco Treasurer

Ronald Tanco Auditor

Christian Noel Cantero DIWATA-1. Image credit: Official Gazette of the Republic of the Philippines

The year 2016 is a milestone in the Philippines’ goal to have a space program. This year Diwata-1, the country’s first microsatellite, started orbiting the Earth and beaming back pictures it has taken of the planet.

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Public Relations Officer

Bruno Exiomo Members

Kashogi Astapan Leogiver Manosca

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Jupiter uno

finally arrives at

After a roundabout five-year trip, NASA’s spacecraft Juno finally arrived inserted itself into an orbit around Jupiter this year. It is only the second spacecraft to orbit Jupiter, following Galileo spacecraft that orbited the king of the planets from 1995 to 2003.

Juno is named after the Roman goddess who was the wife of Jupiter. (Many of the moons of Jupiter, including its four largest, are named after the consorts of the Roman god from which the gas giant is named.) In Roman mythology, Jupiter hid behind clouds to cover up his deeds from his wife.

Juno, however, was able to see through the clouds and find out what Jupiter was up to.

formation of Jupiter are very important because Jupiter is the largest planet in the Solar System and the second largest body in it after the Sun. It contains a majority of the planetary mass within our celestial neighborhood. Hence, finding out how it formed will help us figure out how our own planet formed.

Juno is also a record-breaking mission. Because it will operate near Jupiter in a way no spacecraft ever did, its instruments had to be extremely secured from the gas giant’s unforgiving radiation. Unlike all previous missions that far from Earth Juno is not nuclear-powered. Instead, it is powered by the Sun. Because of its distance from the Sun, its solar panels had to be very big, the biggest for a planetary space probe.

After its 20-month mission, Juno is scheduled to crash into the planet that it is probing.

The Juno spacecraft was designed to see through the upper layers of Jupiter’s cloud cover, allowing scientists to see what’s happening underneath. Juno is equipped with different instruments that allow it to measure many of Jupiter’s stats such as the amount of water, the strength of the magnetic and gravitational fields at different places, the brightness of the auroras, and variations in composition, temperature, and pressure at all latitudes.

Juno’s unique orbit around Jupiter was designed to help it gather the stats mentioned. It will orbit Jupiter in a highly eccentric orbit that goes from pole to pole. Most of the time, it will be far away from the gas giant, moving slowly because of the weaker gravity. At regular intervals during its orbit, it will come very close to surface clouds of the Solar System’s biggest planet. It will scan Jupiter from one pole to the other, allowing it to monitor Jupiter from all latitudes.

One of Juno’s primary mission is to measure the amount of water in Jupiter. This will help scientists narrow down the possible candidate theories for the formation of the planet. The theories about the

As of this writing, SpaceX has replicated this feat four times.

Counting the times SpaceX successfully landed and recovered a first stage Falcon 9 on firm ground, this brings the total to six successful landings.

Artist’s depiction of Juno above Jupiter’s north pole. Image credit: NASA

SpaceX successfully lands a Falcon 9 rocket on a drone ship – four times After several failed attempts, the private space company SpaceX finally makes a successful landing of the Falcon 9 first stage rocket on a floating drone ship in the middle of the sea.

The goal of Elon Musk, the founder and CEO of SpaceX, with these test flights and landing is to develop a technique that will allows space agencies to recover and reuse of rockets parts. Previously, rocket parts ended up being discarded into the ocean.

This increased the cost of sending objects of space, because a new rocket is needed for every launch.

The success of the tests done by SpaceX means there can be a way to send objects to space and wait of the rocket to return and land safely so that it can be reused later. This has the potential to lower the cost of sending spaceflight and thus usher in a new age in the exploration of the final frontier.

THE APPULSE STAFF Publisher

Carlo Andrion Editor-in-Chief

Lanz Lagman

China completes largest radio telescope in the world telescope in the world. The telescope that previously had this record is the famous Arecibo Observatory in Puerto Rico. It has a diameter of 305 meters.

FAST’s bowl shape allows the telescope to gather radio signals coming from outer space and focus it to a receiver. It’s aperture of 500 meters allows it to gather more signal than smaller telescopes. For telescopes, the larger the aperture or collecting area, the greater the power.

An aerial view of FAST. Image credit: Xinhua News Agency

In September of this year, China opens for business the Five hundred meter Aperture Spherical Telescope (FAST), the world’s largest ever radio telescope.

As the name suggest, it is a bowl with a diameter of 500 meters. Russia’s RATAN-600 system is 576 m in diameter. However, its collecting surface is a large ring rather than a disk. Meanwhile, FAST has the largest filled-in single dish of any radio

Like the Arecibo Observatory, FAST was built on a large natural depression in the terrain. It was intentionally built in an area with a karst topography that resulted in many hills that can block out radio interference.

FAST will allow scientists a view of the universe through radio frequencies like never before. Using FAST, scientists can hunt for faint pulsars, map the gas clouds enveloping distant galaxies, and even search for signs of possible signals coming from extraterrestrial civilizations.

China also announced this year its plans to begin new science projects aimed at detecting more gravitational waves.

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Assistant Editor-in-Chief

Jan Marvin Goh Consultant

Angelica Y. Yang Correspondent

Jeffre Blanco Lay-out artist

Al Auacay

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James Webb Space Telescope finally completed, being prepared for launch the successor of the greatly successful and widely popular Hubble Space Telescope, was completed this year and is now being prepared for launch in 2018.

Being seen as the successor of Hubble means the JWST has some huge shoes to fill. Since the mid 1990s, the Hubble Space Telescope has expanded our view of the universe like never before and ushered in a new age of astronomical discoveries.

With its 2.4-m mirror, Hubble showed us how a very small dark patch of sky that looks empty when viewed via the naked eyes is actually full to the brim with galaxies. By zooming into that dark patch, Hubble gave us perhaps one of the most powerful images in the history of science, the Hubble Deep Field image filled with hundreds of thousands of galaxies representing billions and billions of stars.

With a mirror 6.5 meters wide, the JWST is set to usher in a new wave of discoveries. To do this, it must survive launch first. And that is what the scientists are doing now and for next year, test Webb’s construction to see if its parts, especially its gold-colored ultra lightweight beryllium mirrors, will survive being shaken.

Members of JWST team posing with a full-scale model. Image credit: NASA

Webb’s mirrors are one of its unique aspects. Instead of having just one large mirror like earlier telescopes, Webb’s primary mirror is made of 18 separate The James Webb Space Telescope (JWST or Webb), what is seen by many as the segments whose position relative to each other can be unfolded after launch and thereafter adjusted. successor of the greatly successful and widely popular Hubble Space Telescope, was completed this year and is now being prepared for launch in 2018.

JWST also has a tennis court sized Sun shield to protect its instruments from Being seen as the successor of Hubble means the JWST has some huge shoes the intense energy coming from the Sun. Some described it as a sunblock with to fill. Since the mid 1990s, the Hubble Space Telescope has expanded our view an SPF of millions. of the universe like never before and ushered in a new age of astronomical disIf successfully deployed in 2018, Webb will be used to hunt for exoplanets, coveries. watch stars being born, study objects within our Solar System, detect light from the earliest moments of the universe, and beam back gorgeous pictures of the The James Webb Space Telescope (JWST or Webb), what is seen by many as

The universe has 10x more galaxies that previously thought Even before the launch of a new, more powerful space telescope to replace it, Hubble still has surprises to uncover. A new analysis of data gathered by the Hubble Space Telescope suggests that there might be 10x more galaxies than we previously thought. This brings the total number of galaxies in the universe to 2 trillion galaxies.

Careful study of deep space image and other data from the Hubble Space Telescope suggested to sc ientists that there might be more small galaxies than they have previously estimated. The number of galaxies is so huge. Scientists are not able to count them one by one. The number is only estimated from the light gathered by telescopes like Hubble.

Old estimates based on how bright galaxies are in the neighborhood of our Milky Way galaxy, resulted in an estimate of 200 billion galaxies.

More recent data, however, shows that there are more dim galaxies the farther away you look. Since looking far into deep space is also looking back into the history of the universe, this new data suggested that the stars in the universe must be distributed mostly among many small galaxies instead of fewer large galaxies. This means that the change in the estimated number of galaxies to 2 trillion does not mean there are Ten times more stars than previously thought; the number of stars is unaffected by the analysis.

This ten-fold increase in the number of galaxies in the known universe implies that preciously, 90% of galaxies were thought not to exist and were therefore not studied closely. With 90% of the galaxies still waiting to be studied, it’s a great time indeed to be an astronomer.

Earth-sized planet found orbiting around Proxima Centauri The successes of the Kepler Space Telescope and other efforts to hunt exoplanets have made common the once astounding announcement that a new “Earth-like planet” was discovered.

Sun. This breaks the record of the previous

closest rocky planet, which is somewhere around 40 light years away. As a bonus, the planet is thought to be within the “Goldilocks zone” of Proxima Centauri.

Artist’s rendering of Proxima b’s surface. Image credit: National Geographic News

Based on indirection measurements of how it makes its parent star wobble, the exoplanets, called Proxima b, is estimated to have a mass comparable to the Earth. Its size is probably 1.3 times that of our own planet.

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Unlike the Earth, which orbits the Sun once every 365.25 days, Proxima b orbits Proxima Centauri once every 11.2 days. This means that it is very close to its parent star. However, Proxima Centauri is red dwarf star. Compared to the Sun, it is relatively dim and cool. Which is why even at Proxima b’s distance, it is neither to hot nor too cold for liquid water to exist. It is within the Goldilocks Zone, the zone around the star thought to be the prime spot for possible existence of extraterrestrial life.

Proxima b’s proximity to the Earth makes it very interesting to people who search for possible signs of life elsewhere in the universe. The fact that Proxima Centauri is a red dwarf is also a big plus, because red dwarfs live very, very long lives.

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This means that if there is life on Proxima b, it would have had a longer time to evolve compared to us here on Earth. If there are intelligent life forms there, we can also easily communicate via radio signals because the distance is not very long.

But those are big ifs. The detection of Proxima b is indirect, so we don’t really know what kind of atmosphere it has. The fact that it does not transit in front of Proxima Centauri as viewed from Earth also means we can’t yet know what the composition of its atmosphere is.

Still, the discovery got both scientists and the

public excited about prospects of discovering other nearby exoplanets in the near future.

I would like to take the moment to give a special mention to two other interesting discoveries of exoplanets made this year. One was a rocky planet bigger than previously thought possible.

Named BD+20594b, the planet is estimated to be half the diameter of Neptune but made entirely or most of rock.

Its estimated mass is 16 times that of the Earth.

If these estimates hold, this planet challenges existing theories on the formation and stability of rocky

planets by setting a new upper limit for their size and mass.

A second special mention goes to planet CVSO 30c that takes nearly 27,000 years to go around its parent star. While most other exoplanets are discovered by indirect methods, such as the transit method used by Kepler or the radial velocity method used to discover Proxima b, CVSO 30c was discovered by via direct imaging. To provide comparison, Neptune takes 165 years to go around the Sun while Pluto takes 248 years. The hypothetical Planet 9, which might be discovered soon, probably takes somewhere between 10,000 to 20,000 years to complete an orbit.

NASA to make all of its public-funded research freely accessible My number 9 pick for this year’s awesome space news is not about a particular scientific discovery, but about the sharing of such discoveries. The National Aeronautics and Space Administration (NASA) announced this year that it would make all of its public-funded research free to access. The research can be accessed through the public portal Pubspace.

This is big because the progress of modern science builds on often large, international collaborations. A free to access online portal to all of NASA’s research will make such collaborations easier. It will also spur many underfunded researchers from the developing world to increase their collaboration. It has the potential of breeding many would-be first-rate scientists from all corners of the world, not only from places that are affluent.

The announcement comes after the White House asked research agencies to make it easier for the public to access research funded by their tax money. NASA’s Pubspace will allow anyone with an Internet connection to access all peer-reviewed, NASA-funded papers and journal entries. The agency promises to make new data available for reading, downloading, and analysis within one year of publication.

When it comes to declaring that science is for everyone, NASA truly walks the talk.

Saturn’s hexagonal storm changes color The storm, often called “the hexagon” of Saturn, was initially greyish blue when the Cassini spacecraft first started observing it in 2009. However since this year, it has changed to golden-brown.

The reason for this change in color is still a mystery to scientists, although many theorize that it is due to the approaching summer of Saturn’s northern hemisphere. The northern half of the ringed planet will experience its summer solstice in May of next year. The additional sunlight might have triggered chemical reactions that are light dependent. The chemical products of these reactions are probably what resulted in the color change.

The hexagonal wind system is also proposed to act as a fence that isolates the gas inside from the system outside. This can allow the concentration of certain chemicals within the hexagon, which might explain the change in its interior color.

The Cassini spacecraft that spotted this change also recently took close photos of Saturn’s largest moon, Titan. Close pictures of the moon revealed that it might have dynamic islands that appear and vanish in the middle of its hydrocarbon lakes and seas. Titan hosts of an atmosphere thicker than the Earth’s and large bodies of liquid methane.

Some scientists are proposing that the so-called “magic islands” that appear suddenly might actually be gigantic, slowly moving waves on the surface of Titan’s methane seas. After more than a decade of investigating this most interesting of moons, scientists still find more Titanic mysteries to solve.

Just last month, Cassini also dove right through the gas giant’s peerless ring system. Scientists call this phase in Cassini’s mission its entry into “ring-grazing orbits”. These orbits will take Cassini closer to the rings than any space probe ever came. This will provide us breathtakOh, in case you don’t yet know, Saturn has a storm in around its north ing views of Saturn’s dynamic rings and the moons that shepherd the pole that is the shape of a hexagon. Yes, you read that right. And as if that particles that make up the rings, moons such as were not strange enough, it started changing color this year.

Pandora, Atlas, Daphne, and Pan.

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NEAR-MISSED ADVENTURES WITH LUNA’S MESMERIZING FACE

by JEFFRE BLANCO

She always floats although she does not wear a cape. If you shout “help!” from her, expect to receive a cold, blank, luminous stare, she even appears eternally not offering someone bits and slices of care. What can Luna, or the moon, do for you? Nothing. She remains floating above for you to look and wonder. One of

her significant appearances was a glimpse of Supermoon.

She always floats although she does not wear a cape. If you shout “help!” from her, expect to receive a cold, blank, luminous stare, she even appears eternally not offering someone bits and slices of care. What can Luna, or the moon, do for you?

Nothing. She remains floating above for you to look and wonder. One of her significant appearances was a glimpse of Supermoon.

Supermoon is a term coined by Richard Nole, an American astrologer. Technically, it is defined as a “new or full moon that occurs when the moon is inside the 90% of its approach to the earth in a given orbit.” It is also known as perigee moon. But this event is an extra-special one. Why? Because the moon passes closest to the earth in 68 years, and this means that we can view our celestial neighbor in its biggest size. If you miss this event, you can still wait for the next supermoon - in 2034, that is. National Aeronautics and Space Administration (NASA) even claimed that a supermoon can be bigger by 14% and brighter by 30% compared to its opposite, the apogee moon.

Series of Photos by Abdur Alindao through his astrophotography equipment, taken starting at around 9:30 PM

November 14, 2016 - around 7:21 PM, was the moment of truth. As expected, this event occupied a significant portion of tonight’s news and they even showed clear captions of the moon as it rose from the horizon. It was a sight to behold, even on TV. The video focused an almost full moon, as occasional translucent clouds passed through it. To be sure, I peeked at the window to check if I can see anything. It seemed that the moon has just risen, as it is still blocked by my neighbor’s 2-story house across the street.

Initially, I haven’t found this event interesting.

Even though the moon will pass closest to the earth in decades, its size and appearance will remain almost the same to the naked eye. In fact, another amateur astronomer has even branded the excitement over this as a mere hype. But due to the media constantly broadcasting this event, my interest has picked up. I left my computer table and went outside. When I looked towards the sky, I saw the full moon shining in its full glory.

I can say that it appeared somewhat larger and brighter than usual.

The moon’s mean distance from the earth is around 384,402 kms. But the actual distance varies because of eccentricity of its orbit - at around 0.0549. It’s can be as close as 356,500 kms from the earth at its perigee - the point where the moon is closest to the earth. On the other hand, it can be as far as 406,700 kms at its apogee - the point where the moon is farthest from the earth. There are several supermoon events this year. The recent one received special attention because of its close distance to the earth.

When I learned that this supermoon would be the closest (and consequently, the largest), I noticed that people in discussion fora and social media suddenly became excited. Teeming with excitement. I found this scenario amusing because most of the time, whenever I read forums containing news about science and technology, meaningful discussions are rare. This time, people appreciated some of the celestial events which regularly happens, but usually ignored.

At 7:45 PM, I went outside again and to my dismay, I found the moon being covered by clouds. Thick, opaque clouds. The cloud cover is so thick that even the bright light coming from the moon can’t pass through. This is what happened for an entire hour. After failed several attempts of looking at the sky, I decided to give up.

My enthusiastic father repeatedly urged my mother to go out and take a look at the supermoon. He insisted that she should go out as the moon is still surrounded by thick clouds, and is in the brink of being covered again anytime soon.

But the funny thing is that, whenever my mother came out to look at it, she saw nothing. She scolded my father because of this. Consequently, my father just laughed and said: “You’re such a slowpoke that’s why you never see the moon.”

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At 8:45 PM, I made a decision to go outside again and take another look at the night sky. And this time, I succeeded. The clouds has already thinned out, so the moon showed itself again.

I marveled at the grandiose splendour that unfolded before my very eyes for the second time.

I was so amazed that I nearly had a stiff neck because of looking up the sky for quite some time.

Also, the moon was so bright that it drowned the lights emitted by the stars around it completely.

It doesn’t matter, as there’ll be another time for that. Besides, it will be full moon in an hour or so.

I guess I should just concentrate viewing supermoon for now. I took a picture of the moon and headed back inside my house.

My excitement immediately turned to frustration when I saw the picture. It turned out that it is just an overexposed circular blob with no definite feature. I got envious of my PAS colleague Abdur Rahman Alindao, for taking much better photos which showed detailed lunar surface with the help of his astrophotography equipment.

The next day, the news of this event appeared in several newspapers, usually serving the papers’ cover photo. The photos showed a full-featured supermoon proudly shining as it wheezed past the earth the night before. I felt envious for a moment. The photos that were published in the papers were beautiful enough to merit admiration even from the common folks, who are usually ignorant of these events. It put a smile on my face whenever I see someone has stopped by the newsstand to see the supermoon photos. May be they find the photos of Luna a bit too entrancing and mesmerizing for them to ignore. I am hopeful that they will be drawn towards astronomy in the future the moment they see the photos. Who knows? We might even find them joining astronomy groups soon. Supermoon image – captured by the author with his smartphone at around 6:30 PM. Supermoon image – captured by the author with his smartphone at around 6:30 PM.

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Activities of the Philippine Astronomical Society our collective efforts in spreading astronomy education to everyone

October Events

Stargazing at a Full Moon Party

The Philippine Astronomical Society (PAS) conducted its Stargazing sessions last October 16 during the “Full Moon Party” of Sofitel at its wide seaside garden area near the swimming pools and fronting the scenic Manila Bay. The stargazing sessions include targets such as The Eye, distant lampposts and buildings, lights coming from distant ships, etc. Despite the weather being totally cloudy, the event was still successful in conducting a good stargazing session by focusing their telescopes on several distant terrestrial targets.

by JEFFRE BLANCO

PARTICIPANTS – which included PAS facilitators and hotel guests pose in front of the camera before the stargazing event

The event was participated in by guests of various nationalities who little by little, made the crowd grow bigger and filled the grounds with people who were amazed at what they saw and became interested in questions that concerned astronomy and the

night sky. The PAS facilitators Christian Noel Cantero, Hernan Dizon, John Christian Lequiron, Rizchel Masong, Ronald Tanco, and Jeffre Blanco attended to their queries and concerns. What appeared to be a wasted endeavour turned into a night of socialization and friendly exchange of stories and ideas. The PAS facilitators were also warmly welcomed by Francois Punzalan, Sunset Bar’s manager who served as their main contact person. Sunset Bar sponsored food for the event. This is an outdoor and poolside bar which served buffet-style service inside a room allotted for this establishment where bands performed Bossa nova music.

FACILITATORS – Noel Cantero, refocuses the telescope, as onlookers observe, and John Lequiron, discusses astronomy to another guest.

Miriam College hosts PAS October Meeting

by JEFFRE BLANCO

The Philippine Astronomical Society (PAS), with Miriam College – High School Division, organized a monthly meeting with lecture series with the theme of “On Meteorology: Computer-based Climate Models and Weather Forecasting” last October 8 at LMC viewing Rooms 1 and 2 of the said college.

The lecturers were Philippine Atmospheric Geographical, and Astronomical Services Association Weather Bureau (PAGASA) Chief,Salvador ‘Buddy’ Javier and University of the Philippines’s Institute of Environmental Science and Meteorology (UP IESM) Research Assistant, John Christian Lequiron.

Focusing on the indirect and direct effects of the typhoons and hazard to the public, Javier’s lecture about ‘Weather Forecasting Terms: What Do They Mean?’ informed various, familiar meteorological terms used in practical forecasting,

PARTICIPANTS – which include PAS members, students, and lecturers posed for a group picture after the event

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LECTURERS – from left: University of the Philippines’s Institute of Environmental Science and Meteorology (UP IESM) Research Assistant, John Christian Lequiron, Philippine Atmospheric Geographical, and Astronomical Services Association Weather Bureau (PAGASA) Chief, Salvador “Buddy” Javier, and PAS member, Resty Collado

Meanwhile, Lequiron’s lecture on ‘Teaching Meteorology Using Climate Modelling’, or EdCGM, proved the vital role climate modelling offers to meteorology enthusiasts, practitioners, and professionals. A program called EdCGM developed by Columbia University made modelling simpler for the public. Furthermore, he demonstrated a sample program to further illustrate his points.

Although students are hesitant to ask questions because of the lecturers’ positions, their interest lead them to participate by asking questions. The lecturers’ way of explaining their lectures in laymen’s terms amazed the audience. As a result, students learned concepts about meteorologists’ trade both in office and field with ease.

The Chairman of the Events Committee, Hernan Dizon, initiated a group picture which included all the participants and lecturers.

Before the event ended, participants socialized with guests and students. Meteorology, a field usually associated and contrasted with Astronomy, proved to spark both interest and enjoyment for the participants.

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November Events

Instrumentation in Astronomy: The Science behind the Telescopes The PNUScience and Technology Club (STC) in cooperation with the Philippine Astronomical Society Inc. (PAS), held its monthly lecture forum last November 19, 2016 at the By: Christian Dave A. De Leon Geronima BSE major in General Science T. Pecson Philippine Normal University – Hall Auditorium Manila of the Philippine Normal University, Manila. The theme for this month’s lecture series is entitled “Instrumentation in Astronomy” which gave the audience a lot of ideas about the different tools used for the study of the heavenly bodies.

Before the start of the lecture series, there was a short hands-on manipulation on how to use a telescope at the PNU grounds. The lecture proper started with the 1st topic entitled “Converging Lights”, given by Mr. Christian Noel T. Cantero, an alumnus of the Philippine Normal University and a notable PAS Board of Directors member., which was all about the telescopes: on its nature, the different types and when they are used, and how to manipulate, and maintain a telescope. The 2nd topic was entitled “Astronomy Instrumentation: Spectrometer”, which discussed about the spectrometer, the related laws of of Directors member, which

Blue Eagle visits Red Lions

by: Arthel Gavino Teacher at Ateneo Grade School

The adviser of The Bedan Society of Young Astronomers (BYSA), Mr. Pablo Caigal, headed the young astronomers of Ateneo Grade School AstroBlu, with San Beda Senior High School

students, RTU AstroSoc and AGS-Astro-Blu, into a lecture-symposium entitled LIFE IN THE UNIVERSE AS WE KNOW IT on November 15.

The lecturers Engr. Camilo G. Dacanay, the Chairman of the Board of Philippine

was all about the telescopes: on its nature, the different types and when they are used, and how to manipulate, and maintain a telescope.

The 2nd topic was entitled “Astronomy Instrumentation: Spectrometer”, which discussed about the spectrometer, the related laws of physics about it, and how it is applied in the study of astronomy.

Participants group together at the stage for the group picture.

Images courtesy of PNU-STC, Lanz Lagman and Leah Villalon

The said topic was delivered by Mr. John Christian B. Lequiron. At the end of the lecture forum, an open forum was conducted for the participants to ask the resource speakers about their queries on the related topics given. Before the event ended, Mr. Edmund Rosales, took the stage and gave a short, impromptu lecture about the super moon that occurred last Nov. 14, 2016 and other updates in astronomy.

Edmund Rosales takes the stage for his impromptu lecture.

The event concluded with a group picture with all the PAS members, resource speakers, and the participants from different schools and organizations.

Indeed, this month’s lecture forum was a funfilled activity that enriched our minds more about the tools used in astronomy.

PNU-STC President Christian Dave de Leon aligns a solar telescope at the PNU grounds.

John Christian Lequiron conducts his lecture.

Christian Noel Cantero conducts his lecture.

Astronomical Society, and Mr. Rustico M. Hernan the Vice-President of Philippine Astronomical Society, gave their inspirational speeches and shared their experiences through the years with PAS.A mix of astronomy, biology, chemistry and also physics was theme of the lectures. The question of “Are we alone?” has been focused by the lecturers.

After the discussion, Mr. Rustico M. Hernan promoted the organization to inspire the students of San Beda College, RTU, and the pupils of AstroBlu. The audience were very active on the Q&A portion, especially the pupils of AstroBlu. The Bedans were amazed on how the pupils interact and their adviser was very pleased to see young people who are interested in astronomy.

The BYSA and the AstroBlu look forward to have collaboration in engaging the interest of young people in astronomy. These new ties prove that learning and having awareness outside the Earth’s layer is a great contribution in the field of astronomy.

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The participants pose for the group picture.

Images courtesy of: Bedan Society of Young Astronomers

Arthel Gavino stands beside Pablo Caigal and Astroblu members.

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December Events

Geminids 2016: Stargazing at the

Big Handy’s Grounds “Catch a falling star, sleep under a million stars, peek into the heavens through telescopes, listen to the astronomer-hobbyists as they tour you around the skies, bond with like minds and hearts under the mantle of the cold dark Christmas night.”

By May Reyes Serrano Owner, Co-Steward at Big Handy’s Grounds

Once again, the year-ender stargazing event of the Philippine Astronomical Society was held at our place, the Big Handy’s Grounds located at Tanay, Rizal in December 10-11, 2016. More than three hundred participants came to the site and stayed overnight to watch the Geminids meteor shower.

I learned that the event was planned six months in advance; due to the frequently huge number of participants from the previous stargazing events conducted at the same site. Therefore, the way the event was organized was very streamlined. The meeting place was at the Araneta Coliseum at Cubao, Metro Manila. Six buses, each named after a star or constellation, were hired. Two designated facilitators that are wellknown PAS members were present at each bus in order to orient the participants. Due to the unexpected traffic encountered by the buses at their travel from Cubao to Tanay, the participants finally assembled at the site at around 5 pm to finally settle down for the night and set up their tents.

When the night came, everyone was prepared.

The facilitators have set up several telescopes and entertained the participants that wandered around and asked questions. For the next hours, the grounds were filled with the sound of amazement made by several groups when they spot a meteor together. Yes, the moon and the clouds made their presence felt. With that though comes a wonderful energy, a shared wish to see stars, and, because nature listens and is kind, every time a window did open up, it was stellar! The awe, the amazement, the unquestionable connection star children make when we are introduced to our cosmic origins, our “old ‘hood”, never gets old. There’s an almost audible click in the brain and an unmistakable twinkling of the eye, that is more than a reflection of the stars we’re watching and it fills my heart to witness these beautiful phenomena unfold. It was a mix of astronomy lectures, bonding under/with/through the stars, rest and information processing

Photo Gallery of Geminids

Biethday Celebration with the stars by Bernice Pangan

Canis Major by Grant

PAS Public Relations Officer Bruno Exiomo poses with a telescope. Photo by Kashogi

Orion by Grant

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periods and the ever present selfie sessions and just BEING under the stars.

From our vantage point as water tank guardians in the middle of the campsite, we had an unforgettable “surround sound” experience. We could hear the ongoing lectures that elicited aaaahs of understanding and giggles from the fun facts and astronomy puns, we could hear that signature Hugot that comes from being in romantic setting minus the desired partner. We heard lone wolves plugged into their earbuds softly singing lost in their own music, we heard an amusingly boisterous astronomy discussion and as an added treat, Christmas carols on a violin. Unfortunately for me, sleep won after spotting 4 meteors and Orion was high in the sky but I was happy to be awakened in intervals by the excited yells of meteor spotters like a syncopated alarm clock whose chimes varied depending on how many people spotted the meteor and on 2 occasions, ongoing conversations were cut short and an almost unanimous ooooh emanated from the campsite. They must have been a big one! It is high on my list of happies to be a part of any event where people are cheering for nature and to know that at any given moment, there were at least a hundred people with eyes to the skies.

Even though the Sun started to rise, everyone’s energy is still up. Our enthusiasm still persisted even as we assist the participants in packing up and taking several group pictures. As they leave the site on their buses, we can assure in our hearts that there will be more to come.

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Group Photo taken before departure by Al Auacay

Aerial Footage Captured By Al Auacay, Drone Pilot Ernie Serrano

The Moon at Waxing Gibbous by Abdur Rahman Alindao

PAS Facilitators pose for a timed photo. Photo by Kashogi Astapan

Dakilang Maninilip by Paul Norman Go

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Cosmic Collectives

thoughts, discussions and works concerning astronomy

Astronomy as the Midwife

of Modern Science

A

stronomy is the

midwife of modern science. This is one of the many reasons why we must study astronomy. It is the very discipline that By: Pecier C. Decierdo ushered in the Science Education Officer scientific The Mind Museum revolution.

What do I mean when I say is astronomy the midwife of modern science?

A midwife is someone who aids in the delivery of a newborn baby. Astronomy was the discipline that aided in the transition of the proto-science into modern science.

After all, they had little reason to believe that the Earth was turning on its axis of moving around the sun.

saw through the telescope that the moon had hills and valleys that looked like the Earth’s, although they are barren of life.

However, Ptolemy was a stickler of details.

Such an approach, you might recall, is one of the hallmarks of the scientific attitude.

Second, contrary to the Ptolemaic model that said the Earth was the center of the universe and everything went around it, he discovered the four big moons of Jupiter that now bear his name. He saw that these moons – Io, Europa, Ganymede, and Callisto – went around Jupiter instead of around the Earth.

Ptolemy used the observations of the positions of the planets in the sky by the people who came before him. He also kept very careful records of his own observations. Because of his penchant for details, he noticed that the predictions he drew from the accepted model of the solar system failed to account certain observations. For example, Mercury and Venus were always found close to the Sun. For another, Mars sometimes moved “backwards” for a time, a movement they called retrograde, only to move “forward” again much later, a movement they called prograde.

To make the model account for these discrepancies, Ptolemy added a feature. He thought that the planets did not go around the Earth directly.

Instead, he thought that they went around a point, which went around the Earth. He called these orbits upon orbits epicycles.

What are the proto-sciences? They were the disciplines that were going to be science, but they were still intimately entwined with pseudoscience. Chemistry, for example, used to be indistinguishable from alchemy. Medicine used to be indistinguishable from many pseudoscientific disciplines such as phrenology. Before the scientific revolution, people did not make the distinction between the science of astronomy and the pseudoscience of astrology.

When he tested his new model, it still failed.

There were times when the planets moved faster and times when they moved slower. What’s going on? Ptolemy and his students added even more epicycles - epicycles upon epicycles. They also tried to determine the speed of each epicycle. The epicycles turned in a very complicated way, they thought. Generations of astronomers took the task of refining Ptolemy’s model of the universe. They took increasingly detailed and careful observations of the motions of the sun, moon, and planets. Using these observations, they tweaked Ptolemy’s model so that it accurately predicted the motions they observed. It got very complicated at times, with epicycles upon epicycles upon epicycles upon… you get the idea.

What are the hallmarks of modern science that distinguish it from pseudoscience? First, science is very strict on the requirement of testability. For a theory to be scientifically sound, it must be capable of being tested against observation and evidence.

Enter the mathematician Nicolaus Copernicus.

Being a mathematician, Copernicus had a penchant for simplicity. In particular, he was interested in a simple model that could predict a complex phenomenon.

Second, and this is because of the first, science is very strict on the details. Science has very high standards on what counts as evidence, on what can be considered a confirmation. The slightest deviations of the observation from the prediction means there is something wrong with the theory on which the prediction was based.

Third, science requires logical consistency.

The correct theories of science must not contradict each other.

Fourth, science does not respect authorities.

There are experts in science, people who dedicate their lives to study a particular aspect of nature. But even the experts’ ideas were subject to the same strict and stringent tests to which everyone’s ideas were subjected.

These are just some of the hallmarks of modern science. Their more widespread observance is what ushered in the scientific revolution. We can begin our story of how astronomy ushered in the scientific revolution with Greco-Egyptian astronomer and mathematician Ptolemy. Ptolemy wanted to know exactly how the planets moved. However, like many thinkers during the time, Ptolemy thought that the Earth was not only the center of the Solar System but the center of the universe. At the time, people imagined the stars to be embedded in a large sphere they called the celestial sphere. (Nowadays, we know that this sphere is imaginary and is just a useful fiction in studying the motion of celestial objects.) The Earth was at the very center, surrounded everywhere by this sphere. Inside this sphere and going around the Earth were the sun, moon, and planets.

All of these celestial bodies moved around the Earth in perfect circles. Many even imagined the planets to be embedded in perfect, spherical orbs.

Ptolemy accepted this view of the universe.

In his search for a simple solution, Copernicus discovered that all of the complicated epicycles could be gotten rid of only if we imagined the sun at the center, not the Earth.

“Astronomy was the discipline that aided in the transition of the proto-science into modern science” Copernicus’ suggestion was shocking to many people at the time, and there are two main reasons for that. First, it went against the dominant belief that the Earth had to be at the center. This belief was linked to the fact that Earth was the most important place in the universe, that everything that happened in the universe had something to do with events here on Earth and the affairs of its people.

Third and most powerfully, he saw that Venus exhibited different phases. Not only that, he saw that as Venus goes through its phases from full to half to crescent, it increased its size. This observation will only make sense if Venus went around the Thus the fate of Ptolemy’s model of the universe was sealed. The way is open for the alternative – Copernicus’ model, with the sun at its center.

Enter Johannes Kepler. Kepler was the student and heir to the data of the great Tycho Brahe.

Brahe was a very meticulous astronomer, and his observations of the positions of the planets were superb. In fact, they were so good he had trouble modifying the Ptolemaic model to make it agree with his excellent observations. The competing model of Copernicus was already available at the time, but Brahe was insistent on the truth that the Earth had to be at the center. Furthermore, Copernicus’ model still assumed that the paths of the planets around the sun were perfect circles, and this also lead to inaccuracies of their own. Contrary to Brahe’s dying wishes, Kepler adhered to the sun-centered model rather than the Earth-centered model. However, he noticed that if he followed Copernicus’ assumption about circular orbits, the predictions do not fit the observations perfectly.

Hence, he went back to the drawing board and used Brahe’s observations to figure out the laws that described the planet’s motions.

He found out the following.

First, planets went around the sun not in perfect circles but in ellipses. The sun was at one of the two foci of the ellipse. (Or, more accurately, the center of the sun was coincident with one of the ellipses foci.)

Second, he discovered that the planets’ motion around the sun was not uniform. Instead, it’s the sweeping of the angle made by the line connecting the planet and the sun that had uniform motion.

This resulted to a motion of the planets that was fastest when they were near the sun but slowest when they were farthest.

Third, he found out the pattern that predicted how fast a planet would go around the sun given how far it was.

To this day, these laws are called Kepler’s laws of planetary motion. They are an example of what are known as ‘empirical laws’ in science. An empirical law is a law that was derived from observation.

They usually don’t include explanations of why the pattern holds.

Second, it went against most people’s common sense that the Earth was stationary. After all, if the Earth turned and went around the sun, shouldn’t we feel a great wind sweeping over the Earth?

Shouldn’t the oceans rise to a high swell and tide over the land?

Kepler’s laws were elegant and beautiful. More importantly, they were extremely accurate and highly predictive. However, they left unanswered the questions people had about a moving Earth – if the Earth turned and moved around the sun, why don’t we feel it?

For this reason, many people admired Copernicus’ work for its beauty and simplicity, but they thought it was just an abstract mathematical tool.

They did not think it represented the real world in any way.

The last character in this story is probably the most famous, and rightly so. His name is Isaac Newton, inarguably one of the greatest minds in the history of human thought.

Enter the great Galileo Galilei. Observant and enterprising, Galileo turned the newly invented telescope towards the skies. He put several nails to the coffin of the Ptolemaic model.

First, contrary to expectations that the celestial realm is made of perfect spheres, Galileo

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On a dare, Newton set himself to the task of finding an explanation for Kepler’s laws of planetary motion. To succeed, he had to invent an entirely new field of mathematics, calculus. Using this new field, his universal law of gravity, and his laws of motion, he found out that all of Kepler’s laws were a consequence of the way gravity behaves and the way objects moved.

THE APPULSE Newton’s law of gravitation and motion were universal. That is, they applied to the entire universe. They explained not just how the planets, asteroids, and comets moved around the sun but also how the moon moved around the Earth, how satellites both natural and artificial moved around their parent body, how binary stars danced around each other, how the ring particles moved around ringed planets, and how the entire galaxy of stars moved around its centered of mass. In one powerful sweep, they explained Kepler’s laws and so much more.

This pattern of discovery showed the world the power of meticulousness, close attention to detail, creativity, and mathematical thinking. It became the pattern for the revolution that came after it, a revolution that produced the modern world.

And remember, it all started with people trying to figure out why the planets seemed to move the way they did. With this, my claim that astronomy is the midwife of modern science is, I believe, proven.

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This is the story of how an apprentice meticulously gathered data and painstakingly analyzed them for decades in order to give us a new picture that led us closer to the truth on how the heavens moved. His groundbreaking work is just one of the gears that lead to the Scientific Revolution that would allow us to break free from the confines of our home planet and reach the once unreachable heavens.

That apprentice was Johannes Kepler (1571-1630). He established his laws of planetary motion after years of hard work analyzing the records of his superior, Tycho Brahe then struggling to fit them to the available models of the Solar System back then.

There are three laws; the first law states that a planet moves in an elliptical orbit around a Sun, with the Sun located at one focus.

An elliptical orbit.

The second law states that the area covered by the line connecting a planet to the Sun sweeps equal areas in equal intervals of time.

This implies that the planet will move faster as it approaches the Sun and will move slower when it is much farther from it. Planets with circular orbits should only have a constant orbital speed.

From Epicycles to Ellipses: Kepler’s Laws of Planetary Motion This is the story of how an apprentice meticulously gathered data and painstakingly analyzed them for decades in order to give us a new picture that led us closer to the

by Lanz Lagman BS Astronomy Technology truth on how the Rizal Technological University heavens moved.

His groundbreaking work is just one of the gears that lead to the Scientific Revolution that would allow us to break free from the confines of our home planet and reach the once unreachable heavens.

The area covered from p1 to p2 is equal to the area covered from p3 to p4.

The third law states that the cube of the mean distances is approximately equal to the square of the period of the planet’s revolution.

This means that the greater the distance of the planet is from the Sun, the slower it revolves.

“I demonstrate by means of philosophy that the earth is round, and is inhabited on all sides; that it is insignificantly small, and is borne through the stars” Johannes Kepler. Image Credit: ESA

In this article, we will discuss how the first law was established by Kepler based on current knowledge and technology available during his time. Afterwards, we’ll tackle how later scientific advancements, some long after his death provided the grounds that finally justified why orbits are elliptical.

Renaissance Astronomy: A Background Kepler lived during the time when there were three models describing the motions of planets; the widely accepted but increasingly questioned Ptolemaic system, the obscure but more realistic Copernican system and finally the forced combination of these two models, the Tychonic system.

From Left to Right: Ptolemaic, Copernican and Tychonic System

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These models tackle the position of the Sun, Mercury, Venus, Earth, Moon, Mars, Jupiter, Saturn and the stars. The main conflict between these models were: 1. What’s at the center of the universe, the Earth or the Sun? 2. What planet is orbited by the others?

According to Ptolemy (100 - 168), the immovable Earth was at the apparent center of the universe with the others surrounding and orbiting it.

Nicolaus Copernicus (1473 - 1543) disagrees at what’s at the center and instead puts the Sun at its center then the others revolve around it. Tycho Brahe (1546 – 1601), the astronomer that Kepler assisted, saw the benefits of the Copernican system and combined it with the more philosophical and religiously aesthetic Ptolemaic system and proposed that the Sun orbits the Earth and the other planets orbit around the Sun. Despite their fundamental differences, they were made for the same purpose: to accurately predict how the planets moved throughout our sky.

Each of these models were proposed and modified at the basis of continuously accumulating data from night sky observations being conducted thousands of years before. Astronomers obtain these data by recording the position of planets at a fixed time, as much as possible, every day.

Remember that the Renaissance is an era when we only have horse carriages for cars, exclusive libraries for Google and selfies could only be made if you’re a skilled male artist, all of these models were made at the vantage point of the three astronomers and they have to observe for decades while working on these, then use the data that the others have collected before. Astronomy is still fused with astrology, not physics This means that the movement of stars and planets are only tracked and the only concern is to make a model that recognizes the pattern of planetary movements, not why do they move like that or what makes them move like that.

It is important to mention that Ptolemy’s work held so much influence that despite the divergence of Copernicus’s heliocentric model, a lot of its elements were retained. One of them was the concept of nested celestial spheres where the planets are embedded in these rotating hollow spheres made of Aether or crystals. The rotation of these celestial spheres is what causes the movement of the planets, therefore the planets move around in circles with unchanging speed. The stars however, are all embedded at the outermost celestial sphere.

Contrary to popular belief, not only these models are similar in terms of accuracy, but also it’s not what’s at the center and which orbits which that dictated the accuracy of these models; it’s how they employed epicycles.

Established Epicycles: What are they for?

The Earth revolves around its axis, that is an example of uniform circular motion. The stars appear to stay in their place at all times, that’s why when you take a picture of the night sky with long exposure (to reveal star trails), the image will look like this.

their brightness during night subtlety varies over time. The illustration above is an example of retrograde motion. Mars, Jupiter and Saturn have been observed to suddenly move backward then move forward again. Segments of perfect circles aren’t supposed to look like that, right? Perhaps the motion is not circular, right? Nope. Enter the epicycle.

appear to speed up but also why retrograde motions occur. However, when the path of the planets of the Ptolemaic system are traced, they’ll look like this.

Star trails. Image credit: Jerry Lodriguss

The stars seem to revolve around the star that’s at the axis of rotation, that the north star, Polaris. Now, since those models say that planets move in uniform circular motion, we expect that when their paths are traced, they’ll look like curved streaks, expected of a segment from a circle, that when connected and continue, will trace like a perfect circle. But then, what’s this?

Movement of Mars in 2003. Image credit: NASA

Soon, the notion of uniform circular motion and geocentrism started accumulating holes.

Mercury and Venus are both unseen at midnight are only clearly visible when the Sun is either starting to rise or set. Planets appear to speed up then slow down and sometimes

Orbits of the Ptolemaic System. Image credit: James Ferguson

Ptolemy’s epicycle

Epicycles literally mean circles within circles. In this diagram of Ptolemy’s model of an orbit, the red circle is called the deferent and the blue circle is the epicycle. The planet revolves around the center of the epicycle then this center moves through the deferent. Now this is the confusing part because these seemingly contradict the notion of circular motion. The center of the epicycle revolves around the center of the deferent called the eccentric at a constant distance; that’s why the deferent is circular. However, with respect to the point called equant, the center of the epicycle revolves at a constant rate. In this way, the planets seem to move faster when they’re approaching our Earth then slowing down when they’re moving away. This was Ptolemy’s clever way of devising his epicycles not only in order to explain why the planets sometimes

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The battle between the models of Ptolemy and Copernicus is interesting in terms of how they used epicycles. Ptolemy altered the size of the epicycles of Mercury and Venus so that his model would explain why Mercury and Venus aren’t seen at night. Ptolemy’s epicycles however are more complicated for they have equants. Copernicus sought to create a simpler model and that’s when he came up with his heliocentric model. Mercury and Venus now revolved around the Sun, a much simpler explanation on why these two can’t be seen at night. The idea of equants is then removed and are replaced by more but smaller epicycles; the Copernican model may have simpler epicycles but it’s more complex than the Ptolemaic system in terms of the number of epicycles. Conclusively, the Ptolemaic and Copernican system ended up having their own complexities but unbelievably, both are almost the same in terms of accuracy. It would be inevitable that these models would prove inadequate when thousands of years’ worth of data are compiled and analyzed; their models are simply not accurate enough.

Everything changed when Kepler attacked.

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Enter Kepler

Tycho Brahe at Uraniborg. Image credit: Astronomiae instauratae mechanica

Johannes Kepler was employed in 1600 by Tycho Brahe as an assistant in his observatory and castle Uraniborg, located in Hven, Sweden. Of all the tasks that was assigned to him, the most important one came when Brahe unexpectedly contracted illness. At his deathbed, he instructed his assistant to complete their work on the Rudolphine Tables and use his formerly heavily restricted accurate data to prove his Tychonic system.

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Kepler’s second law was actually discovered before the first. The result of his hard work was the publication of Astronomia Nova (New Astronomy) in 1609. Additionally, geocentricism and the epicycles slowly died in Europe, not only due to Kepler’s works but also due to the discoveries made by Galileo Galilei through his telescopes. These are the phases of Venus and the moons of Jupiter. The observed phases of Venus could not be justified by any geocentric model and modified epicycles and finally, moons orbiting around Jupiter was simply overwhelming because they should be orbiting around the Earth, not Jupiter. The appearance of comets during the Renaissance and the subsequent studies that followed also revealed that these heavenly bodies have highly elliptical orbits, blatantly disagreeing with the notion of uniform circular motion.

Kepler was able to show that planetary orbits are ellipses but he was unable to determine precisely why. It’s just like learning from a friend that a new flavor of pizza tastes great but both of you don’t know what makes it so.

That would be proved some decades later by none other than Sir Isaac Newton (1642 – 1727), who was so badass that he almost singlehandedly invented his own math (calculus) and his own physics (Newtonian mechanics).

Now why would an orbit be probably an ellipse instead of a circle?

Kepler was earlier assigned to analyze Brahe’s observational data on Mars since there were a lot of errors discovered. Kepler was a known adherent of the Copernican system and sought to analyze Brahe’s data in order to prove and modify it.

An egg-shaped orbit versus an elliptical orbit.

The gravitational theory states that everything with mass gets attracted to each other by the gravitational force in an inverse-square distance relationship. In simpler terms, that means that the nearer are the two objects to each other, the stronger they get to be attracted to each other. Objects with greater masses are more attractive, but that may not be a good way to describe how attractive your crush is.

The equation for the gravitational force is expressed as:

In this equation, Fg is the gravitational force, G is the gravitational constant, M and m are bigger and smaller masses of the two objects respectively and r is the distance between them. It’s now easier to understand the concept of inverse-square law; since the divisor is the square of r, that means that doubling the distance of these two objects would mean that the gravitational force between them would be reduced to a quarter of its former value. Combining the two equations, we could produce an important mathematical expression: acceleration due to gravity.

For now, do not mind the weird markings, for they are the result of deeper applications of Newtonian mechanics, taking into account not only the magnitude of the forces applied but also the direction of these forces; in which we will not discuss.

Kepler began his study of Brahe’s data in 1601 and fortunately he concentrated on studying Mars’ orbit. Years passed and he realized that he has to bring back Ptolemy’s equant and modify the Copernican model and he came up with the idea of an ovoid-shaped orbit; which means that it resembles an egg or a teardrop.

He then set out to calculate the egg-shaped Martian orbit using trial-and-error. After multiple mistakes, he finally realized that perhaps, the orbit was elliptical in shape! After repeating his calculations with this new idea and finding out that the Martian orbit was indeed elliptical, Kepler finally declared that orbits in general are elliptical in shape.

These three could be summarized as follows. Newton’s three laws of motion state the following in order: things won’t move unless they’re moved (law of inertia); moving objects would have greater acceleration if more force is applied and lastly (law of acceleration); for every action, there’s an equal and opposite reaction (law of action and reaction). The second law could be summarized as the force applied is equal to the mass multiplied by its acceleration:

Calculus is the mathematical study of change. Newton and Gottfried Leibniz (1646 – 1716) both independently invented it. This new form of math is perfect for accurately describing how slopes become steep and flat at some sections and in this case, how the variations in the speed of planetary orbits influence the shape of their orbits. The full utilization of these principles [in proving the validity of Kepler’s first law would result to this equation.] leads to the following expression.

Sir Isaac Newton. Image credit: Royal Society Print Shop

It was Kepler’s laws of planetary motion that served as one of Newton’s inspirations in searching for a more rational basis on why and how things move in general. In his most famous work, the Principia, Newton established his well-known laws of motion, theory of gravitation and the beginnings of every math-hater’s worst nightmare, the calculus. Together, these three were used to justify Kepler’s laws and in this section, we’ll be dealing on how these concepts bring out the elliptical shape of planetary orbits

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This dictates the distance of the orbiting body from its parent body (r) with respect to time (t). It turns out, if you draw a graph of the expression above, what you get is a special family of shapes called conic sections.

Conic sections are the shapes you get when you slice a cone, hence their name. There are several kinds of conic sections. The kind of conic section will depend on the numerical value of the letter ε. It’s the eccentricity of the conic section and this tells us how much the orbit deviates from a circle! For a circle, ε = 0; for an ellipse, 1 > ε > 0 or in simpler words, an ellipse has an eccentricity greater than zero but less than one; a parabola has ε = 1 and finally a hyperbola has ε >1.

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References 1.Carroll, B. W., & Ostlie, D. A. (2009). An introduction to modern astrophysics. San Francisco, Calif.; Munich: Pearson/Addison Wesley.

2.Caspar, M. (1959). Kepler. London: Abelard-Schuman.

3.Riebeek, H. (2009, June 7). Planetary Motion: The History of an Idea That Launched the Scientific Revolution. Retrieved from http:// earthobservatory.nasa.gov/Features/OrbitsHistory/ 4.Johannes Kepler: His Life, His Laws and Times. (n.d.). Retrieved from http://earthobservatory.nasa.gov/Features/OrbitsHistory/ 5.Williams, D. R. (n.d.). Planetary Fact Sheet - Metric. Retrieved from http://nssdc.gsfc.nasa.gov/planetary/factsheet/

Possible shape of orbits as dictated by their eccentricities.

In fact, by geometric definition, a circle is a special type of ellipse; this means that perfectly circular planetary orbits are impossible to occur in nature. For example, the orbits of the inner planets Mercury, Venus, Earth and Mars are the following: 0.205, 0.007, 0.017 and 0.094. Despite Mercury being the most eccentric among the inner planets, astronomers didn’t notice it at all because Mercury is less-studied, after all it is a fast planet and could not be seen at night when planetary movements are easily analyzed.

“Beyond what the Telescope could See”

by Engr. Ronald Tanco

December 2016

By: Angelica Y. Yang Student Correspondent Philippine Daily Inquirer University of the Philippines, Diliman

The Orbits of the Inner Planets. Credit: NASA’s Eyes

Notice that all planetary orbits are closed; meaning they are not parabolic and hyperbolic. This means a huge amount of force must be exerted upon them to have an open orbit, since as per the laws of motion, they are massive and are therefore harder to move because of more inertia. Spacecraft and comets however, have significantly fewer mass and are therefore easier to accelerate, making it easier for them to achieve an open orbit.

We already knew what happened next. Newtonian mechanics effectively dethroned the method of thinking that resulted in the creation of geocentric models and it became the most authoritative tool for several hundred years for scientists in explaining how everything moves and interact with each other. Soon, Uranus was discovered; a planet too dim for the eyes of our ancestors. Then followed Neptune; whose movements were predicted by Newtonian mechanics, once again solidifying its authority. Who would have thought we would apply what we discovered about how these gigantic planets move would be used as a noble attempt to understand one of the most basic building blocks of everything? The atoms, once considered the smallest unit of matter, were once thought to be miniature solar systems themselves; with the nucleus as the Sun and the electrons as planets.

We as humans must marvel and appreciate at the courage, curiosity, diligence and passion in the search for truth displayed by Kepler, Newton and all other scientists that brought us the Scientific Revolution. In just several hundred years, we may now reach the heavens through our rockets and spacecraft.

We may now finally fulfill what our ancestors thousands of years ago could only dream and marvel for the rest of their lives.

Star guide for the First Quarter of 2017

What better job could be suited for me, If it hadn’t been for the wonderful world of Astronomy?

My first spark of unspeakable passion, Started with a beautiful map filled with many constellations.

I’ve changed my point of view of the world.

To the universe, my thirst for knowledge unfurls.

Supernovae and speeding comets can only satisfy my hungry heart.

All things in this universe cannot be considered technical, but rather, art.

All I want to do is to research and inquire…

Why is my need for Science so dire?

Rockets and spaceships that can reach the highest of skies, An astronomer can live and search, but find nothing until he dies.

People may be afraid of my brain, But aren’t all the geniuses of the world ingeniously insane?

It wouldn’t really matter what’s in my salary, I’d revel in the thought of adventure, of worlds beyond what my eyes can see.

New celestial bodies awaken my senses for investigation.

If I’d discover something really great, I wouldn’t announce it for worldwide emulation.

I don’t care if I spend the rest of my life hiding under textbooks.

I will forever keep searching answers in my one and only nook.

My eyes will be trained up at the starry night sky.

Science is truthful and mesmerizing- it never lies.

I want to be an astronomer, I want to go places I’ve never been, To deprive me of that opportunity would be a grave sin.

I may not win the Nobel Peace Prize, But my work will help civilizations rise, Even when I’m gone, the universe will remember me, For chasing the dreams beyond what my telescope could see.

15

For December, we start the month with an alignment of 3 planets right after sunset. From the western horizon going to the zenith, we should be able to see Mercury, Venus and Mars of about 20 degrees apart from each other. Starting December 1 to about December 6, the moon shall be seen moving just to the north of the ecliptic line of where these planets lies. Closest approach to the Mercury, Venus and Mars on December 1, 3, and 5 respectively. December 7 will be the first quarter moon.

Take the opportunity to try to glimpse the elusive Mercury who will reach its maximum eastern elongation from the sun on December 11. This is best seen after sunset, you will probably have about a week before and after Dec. 11 to spot mercury before it goes close to the sun again on its conjunction on Dec 29.

Regarding the other planets, Jupiter is expected to rise at about 2:30 a.m. in early December to about 12:40 am by the end of December. Saturn on the other hand just finished its conjunction and is slowly breaking away from Sun to be one of the morning planets.

Sadly, the very sought after December 13 Geminids meteor shower falls on a full moon, thus visual observation of this meteor shower will be almost impossible.

January 2017 For those with telescope with high magnification and aperture (and dark skies), you may wish to test your skill in finding Neptune as it will be within the vicinity of Mars.

On January 1, 2017, Mars and Neptune are in near conjunction of less than 0.1 degrees separation! Best wishes to those Neptune seekers.

Once again, like the previous month, we continue to see Venus and Mars visually aligned in the sky but with the absence of Mercury. On Jan 2 and 3 we will see the crescent moon just beside Venus and Mars on their respective dates. But Mars and the moon

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will be very close to each other after sunset on January 3. Sadly, the closest approach of Mars and the moon will not be visible in the Philippines setting. As the days goes by for January, expect Mars and Venus approach each other each day.

Mercury is no longer visible as an evening planet but you should be able to see it in the early morning as it reaches its greatest elongation from the Sun on Jan 19. Again you have about a week before it disappears from visual sight as it goes to superior conjunction.

Venus will reach its greatest western elongation on Jan 12, thus if viewed through the telescope, one should be able to see the planet similar to a half-moon. From this day onwards until its conjunction, expect not only the half phase to shrink to a crescent, but also for the planet to grow brighter and bigger.

For those lunar occultation hunters in the country, January and February offers a treat for observers. On January 9 after sunset, the gibbous waxing moon will pass through the open star cluster of Hyades in Taurus. For the beginners, this also serves as an initiation to view star occultation by the moon and learning about timing. A repeat will occur on Feb 6 early morning.

Other interesting events for January includes the Quadrantids meteor shower whose conditions are ideal for visual observation with only a near first quarter moon on Jan 3. The moon will also be seen to have a close approach to Regulus, and Jupiter on Jan 15 and 19 respectively.

As for the other planets, Mercury will still be elusive as it journeys behind the sun. Jupiter slowly gets brighter with a rise time of about 10:40pm on Feb 1, and 9:45pm on Feb 15.

Saturn is also visible in the early morning with a rise time of 3:05am on Feb 1 and 2:15 am on Feb 15.

February 2017

March 2017

February is almost a repeat of January. At the start of the month, we should see Venus and Mars be at its closest approach to each other on Feb 2. The moon should make it a romantic view as being nearby these 2 planets from Jan 31 and Feb 2 with Feb 1 as the closest approach. In just a few days after the Mars-Venus-Moon occultation, the moon will now journey again into the open star cluster Hyades in Taurus in the early morning of February 6. It may be possible to still see the occultation of the red star Aldebaran by the moon just before sunrise.

Jupiter is almost all set to be viewed as it once again approaches its opposition. It doesn’t mean that you should bring out your scopes only to view Jupiter on its closest approach to Earth on April 9, but March is month to begin enjoying the larger and brighter view of the planet.

There is a predicted Penumbral Lunar eclipse on Feb 11 and an annular solar eclipse on Feb 26, but both will not be visible to the Philippine setting. However, Philippine viewers may appreciate the closest approach of the moon to Regulus on Feb 11 at 10:20pm with less than a degree separation.

Venus on the other hand is quickly getting closer to the sun, both getting brighter and its crescent getting thinner. On Feb 28 and March 1, you should be able to view 2 crescent shaped planets, Venus and the Moon. The month of March will be last opportunity to see the planet as our evening star. After the inferior conjunction on March 25, it will be our morning star on late April and May. Mars will just be in the vicinity of Venus, but you will notice the separation between the 2 planets grow day by day.

Philippine Astronomical Society Astro Calendar 2017 (1st quarter)

By Engr. Ronald Tanco

Date Event December

Time

Remarks

Date

Event

Time

19

Jupiter 2.3 degrees south of Moon

1510h

3

Venus 5.8 degrees south of moon

19

Mercury at greatest western elongation 24.1 degrees

1745h

5

Mars 2.9 degrees south of moon

1720h

20

Last Quarter Moon

0610h

7

First Quarter Moon

1700h

24

1850h

10

Saturn at Conjunction

Saturn at 3.5 degrees separation from moon

11

Mercury greatest eastern elongation

1240h

28

New Moon

0805h

13

Hyades 0.3 degrees south of Moon

event not seen

1

Mars 2.8 degrees N of Moon

1720h

13

Occultation of Aldebaran by Moon 1235h

event not seen

2

14

Full moon

Venus and Mars at minimum separa- 1930h tion about 5 degrees apart

15

Geminids Meteor Shower

4

First quarter Moon

6

Occultation of Hyades by Moon

6

Occultation of Aldebaran by Moon

0535h

11

Full Moon

0830h

11

Penumbra Lunar Eclipse

Not Visible

11

Regulus 0.7 North of Moon

2220h

16

Jupiter 2.8 degrees south of moon

0035h

19

Last quarter moon

0330h

Saturn 3.1 S of Moon

0750h

26

New Moon

2300h

2

Mars 4.7 N of Moon

0520h

5

First Quarter Moon

1930h

7

Mercury at superior conjunction

1250h

11

Regulus 1.4 N of moon

0622h

12

Full Moon

2255h

15

Jupiter 1.9 S of Moon

0535h

17

Saturn at Quadrature

20

Saturn 3.5 degrees separation from moon

1850h

20

Vernal Equinox

1830h

20

Last Quarter Moon

2355h

25

Venus at inferior conjunction

1140h

28

New Moon

1100h

2200h Active from Dec 7 to 17.

Peak on Dec 13. ZHR 120/hr

Regulus 1.0 North of Moon

0210h

21

Last Quarter Moon

0955h

21

Winter Solstice

1845h

23

Jupiter 2.5 degrees south of Moon 0210h

29

Mercury at inferior conjunction

0125h

29

New Moon

1450h

21

1500h

March

January Neptune near Mars

2

Venus 1.8 degrees South of Moon

3

Meteor Shower Quadrantids

for telescope viewers only active from Dec 28 to Jan 12. Peak on Jan 4. ZHR 120/hr

3

Mars 0.3 degrees North of Moon

1440h

4

Earth at Perihelion

2215h

6

First Quarter Moon

0545h

9

Hyades 0.4 south of Moon

9

Aldebaran 0.4 south of Moon

2225h

12

Full Moon

1935h

12

Venus greatest Eastern Elongation 2120h 47.1 degrees

15

Regulus 1.4 degrees N of Moon

best seen before dawn

February

19

1

Remarks

closest approach to the sun at .9833AU visible visible

1210h

16

1220h visible before dawn maybe visible

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