Telescopic Topics # 11 – Galaxy Guts with DeGrasse Tyson

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Horsehead nebula imaged by Hubble Space Telescope Image Credit – NASA, ESA, and the Hubble Heritage Team (STScI/AURA)

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Galaxy Guts by Jaron Bradley

An astrophysicist by the name of Neil DeGrasse Tyson gave a very inspirational and intellectual response answering the question that was asked of him during an interview: “What is the most astounding fact that you can share with us about the Universe”? I have a brief sound clip from the answer he gave which is far more extensive, but this quote can give you, the listener, a brief idea of what his response was about:

“So that when I look up at the night sky and I know that yes, we are part of this universe, we are in this universe, but perhaps more important than both of those facts is that the Universe is in us. When I reflect on that fact, I look up – many people feel small because they’re small and the Universe is big – but I feel big, because my atoms came from those stars”.  “…because my atoms came from those stars”.  (Sound clip of Neil DeGrasse Tyson

What he means by his quote is that high mass stars that became unstable collapsed and then exploded, scattering their fundamental ingredients of life which Tyson deems, “Galaxy guts.” These enriched guts contain carbon, nitrogen, oxygen and many other fundamental elements of life. These elements are fundamental in the birth of solar systems as well as the planets which are included in these young and older solar systems. In theory, solar systems, planets, asteroids, and all forms of life share these, “Galaxy Guts,” because our atoms are indeed traceable. If that’s not a level of profound connectivity, I’m not sure what is. For more information feel free to Google search “Most Astounding Fact” or check out a few books written by Neil Degrasse Tyson.

 

Sources

Llorens, Ileana. “The Most Astounding Fact About The Universe, As Told By Neil DeGrasse Tyson (VIDEO).” The Huffington Post. TheHuffingtonPost.com, 12 Mar. 2012. Web. 24 Mar. 2013

“Neil DeGrasse Tyson – The Most Astounding Fact.” LYBIO Is Helping Improve Reading Skills With Video To Scripted – Text, Words, Quotes And Lyrics. N.p., n.d. Web. 24 Mar. 2013.

Telescopic Topics #10 – The Center of Our Galaxy

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Chandra image of Sgr A* Image Credit – NASA/CXC/MIT/F. Baganoff, R. Shcherbakov et al.

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The Center of our Galaxy by Josh Day

Have you ever wondered what is at the center of our galaxy? Evidence suggests there is a super massive black hole near the constellation Sagittarius, roughly 26,000 light years from our sun lies at the center of our galaxy.  Like our Milky Way, it is thought that most galaxies’ center around a supermassive black hole. The black hole at the center of the Milky Way is named Star Sagittarius A. It is one of at least 19 black holes in the Milky Way alone.

What is a black hole? It’s  “ a region of space time from which gravity prevents anything, including light from escaping”. A black hole is created when a star that is at least 30 times the size of our own sun uses up its nuclear fuel and its core collapses. What happens after is a shock wave that destroys the rest of the star. The core that is left behind is so heavy it creates a region of space-time cut off from the rest of the universe.

Studying black holes is hard as black holes swallow any nearby light making them almost invisible. So scientists have turned their attention to the stars that are affected by the gravitational pull of the black hole. Since 1992 researchers have been following a star, named S-2, orbiting Star Sagittarius A giving the researchers more information on the black hole. S-2 has passed within 16 light hours (roughly 3 times the distance from Pluto to our sun) from the black holes event horizon, or the point of no return. Anything that passes past the event horizon will be sucked towards the black hole by its gravitational pull, not even light can escape its gravitational pull once inside of the event horizon. Scientists now estimate the black hole having a mass of 4.5 million solar masses, or 4.5 million suns. With such a great mass the star S-2 is the fastest known orbiting body traveling at speeds near 11 million miles per hour. S-2 and 28 other stars’ orbits are being tracked giving scientists a better idea of exactly where the black hole is located.

All of this research points to a Supermassive black hole at the center of our galaxy. That’s right an unstoppable force whose gravity crushes stars, and nothing can escape from, not even light, sits at the center of our Milky Way. But nothing to worry about this black hole is 26,000 light years away.

 

Sources

Matson J, 2008 Dec 11. Closing In on the Milky Way’s Central Black Hole [Internet].  Danvers (MA): Copyright Clearance Center, Inc.; [cited 2013 April 5]. Available from: http://www.scientificamerican.com/article.cfm?id=milky-way-black-hole

Broderick A, Loeb A. 2009 Nov 25. Portrait of a Black Hole [Internet]. Danvers (MA): Copyright Clearance Center, Inc.; [cited 2013 April 5] . Available from: http://www.scientificamerican.com/article.cfm?id=portrait-of-a-black-hole

Eckart  A, Schödel R, Straubmeier C. 2005. Black Hole at the Center of the Milky Way [Internet]. Imperial College Press; [cited 2013 April 5]

Telescopic Topics #9 – Carolyn Jean Shoemaker

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Carolyn Shoemaker in 1988 Image Credit: UGSG Astrogeology

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Carolyn’s Comets by Kelsey McDonough

Carolyn Jean Shoemaker, born Carolyn Spellman in 1929, in Gallup, New Mexico is considered to be one of the most influential women in Astronomy today. Shoemaker did not, however, start out as an astronomer; in fact, she had no interest in the science. Carolyn originally received a degree in History and Political science from Chico State College, and then went on to become a junior high school teacher. During her time as a teacher, she met and married Eugene Shoemaker. It was during her marriage that she realized that she had no interest in teaching.  In 1977 Carolyn began working as a field assistant for her husband, an up and coming astronomer. This sparked an interest for Carolyn, and in 1980, at the age of 51, she began studying alongside her husband. It was during this time that Carolyn, her husband, and a man named David levy discovered a comet orbiting closely around Saturn. The comet, later named Shoemaker-Levy 9, was discovered by a photograph, taken on the night of March 24th, 1993. After much research conducted by Carolyn and her husband, it was found that the comet had been torn in to pieces after a very close encounter with the surface of Jupiter sometime in 1992, a very rare occurrence.

After this discovery Carolyn’s husband was killed in a car accident during field work, but she continued to study comets and asteroids on her own. Carolyn studied photographic plates and films using a stereoscope, to find asteroids and comets.  She went on to discover about 800 asteroids and 32 comets, thus holding the record for the most comet discoveries. In 1995 Carolyn shoemaker was named Scientist of the year. Shoemaker continues her extensive studies today.

Astrogeology Science Center (internet). c2002 US Department of Interior.[Cited 2013 Mar 20]. Available from astrogeology.usgs.gov

Comet Shoemaker-Levy Collision with Jupiter (Internet). NASA [Cited 2013 Mar 20]. Available from 2.jpl.nasa.gov

Telescopic Topics #8 – Big Sur Green Flash

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Green Flash in Santa Cruz, California Image Credit: http://www.webexhibits.org/causesofcolor/13D.html

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Big Sur Green Flash / Le Rayon – by Margariete Malenda

Initially, we weren’t drawn to Big Sur by any sort of folklore or scientific phenomena. Most of us didn’t even know what we were about to witness. Yet we sat in an August sunset along Highway 1 and dumbly watched while drivers sped by –thinking of us a group of rag tag tourist kids. Or maybe for those two seconds they saw it too, and dumbly stared at the Green Flash with us.

The sun barely held on to the sea, and the romance of Jules Verne uncoiled in my head, “…if one were to peer into the light of the green flash, they too, would read the very souls of others.”

But that’s not what fascinates me. What fascinates me is the science behind the folklore. The Green Flash is fractioned light. It bends as does wind, or limbs– yet is bent and then dispersed by the earth’s atmosphere.

The sun’s rays shine fractioned as colored wave lengths from red to violet, as the atmosphere stretches and distorts them via atmospheric dispersion. Rayleigh scattering swallows the blue, indigo, and violet rays, and the ozone absorbs the orange and yellow. For the most part, by the time the sun touches the sea, we’re left with red and green overlapping rays – or more so red and green images of the sun. And as the red sun races to set before the green, we’re left to be graced with the top sliver of a sun that is the Green Flash.

It’s seen on only those precious afternoons with a clear view free of clouds or pollution: a stunningly clear cut view for miles to the horizon’s brink. The ocean is a flat, open and perfect stage for the Green Flash to treat us to its brief act.

It’s only the emerald tip of the quiet sun. It’s no dramatic, sea churning, power gifting miracle. It’s not the sailor’s folklore, or the French poet’s song, or even the skeptics’ denial that left me to sit and wait. Rather, I waited to see it for myself, and to understand what the sailors had not: that all of what I was watching and what I was experiencing, and all of what I am living is in the end science.

Sources:

An Introduction to Green Flashes. San Diego (CA): San Diego State University. 2012.

I lived a long time in the tropics and often heard of, but never saw, the “green flash” that is said to occur just at sundown. Does it actually exist, and if so, what causes it? New York: Scientific American. October 21, 1997

Telescopic Topics #7 – Trojan Asteroids

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Trojan Asteroid – Computer generated image of TK7, Earth’s Trojan asteroid. The white dot is the asteroid, the green line is the path.

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Trojan Asteriods by Thomas Bare

Hello, my name is Thomas Bare. Today I will explain what a Trojan asteroid is and about some of the Trojan asteroids in our solar system.

A Trojan asteroid is an asteroid that is being pulled by the gravity of the Sun and a planet to keep it in the same orbit around the Sun as the planet. There are five points around the Sun in reference to a planet that the gravitational pull of the planet and the Sun balance each other out. These points are called Lagrangian points. The Lagrangian points are named L1, L2, L3, L4, and L5. Trojan asteroids are found at L4 and L5. These points are 60° away from the planet on its orbital path.L4 and L5 are also the only two Lagrangian points that the forces of gravity acting on it are all pulling in directions away from the point and not across it.

There are thousands of known Trojans following and proceeding Jupiter’s orbit. It is estimated that there might be as many Trojans as there are asteroids in the main asteroid belt.Very recently in 2010 the first Earth Trojan was found. This asteroid was named 2010 TK7. It hasn’t been found until now because it is always on the side of the Earth that faces the Sun.  There is only a short amount of time that telescopes on the ground can look for these asteroids. The times of day to look would be near morning for the L4 region and evening twilight for the L5 region.

Sources:

Yang B, Lucey P, Glotch T. 2012. Are Large Trojan Asteroids Salty? An Observational, Theoretical, and Experimental Study. Icarus Vol. 223 Issue 1, p359-366. 8p.

Todd M, Tanga P, Coward D. 2012. An optimal Earth Trojan asteroid search strategy. Monthly Notices of the Royal Astronomical Society Vol. 420 Issue 1, pL28-L32.

Telescopic Topics #6 – Spacecraft DAWN

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DAWN mission logo Image credit: NASA/JPL

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Spacecraft DAWN – by Brendan Burke

On September 27, 2007 the spacecraft Dawn was launched from the Cape Canaveral Space launch Complex. This spacecraft is on a mission to visit two objects in our solar system known as Vesta and Ceres. Vesta and Ceres are protoplanets, and are the biggest spacial bodies in the asteroid belt between the planets Mars and Jupiter.  To give a reference for size, Vesta is about the size of Arizona, and Ceres is about the size of Texas.

This mission will take almost a decade to complete.  Its goal is to find out about the early formation processes of our solar system.  These two bodies were chosen because they are similar in size and distance from the sun, but interestingly enough, have very different compositional nature. Vesta developed like the inner planets of our solar system, differentiated and with a dry terrestrial surface.  Whereas Ceres is similar to the outer icy gas planets.  The mission hopes to be able to find out about the formation of these two protoplanets and from that knowledge, learn about the formation of the different planets in our solar system, and what the early solar system might have been like.  Specifically the mission seeks to answer what role size and water play in the evolution of a planet.

The spacecraft is currently on its way from Vesta to Ceres.  It arrived at Vesta in July 2011, and stayed there studying that body until September 2012, when it started towards Ceres.  It is scheduled to arrive at Ceres in February 2015, where it will stay until July of that year when the mission is over.  Anyone further interested in this mission can keep updated through the NASA website which has a log of the mission’s status.

 

Sources:

http://dawn.jpl.nasa.gov/

Telescopic Topic #5 – Rockets and von Braun

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Werhner von Braun in 1961 Image Credit: Hulton-Deutsch Collection/Corbis

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Rockets and von Braun by Darren Dobroski

Dr. Wernher Von Braun was a Nazi engineer who created the rocket technology that would fuel the space race. Inspired by science fiction novels, Von Braun learned calculus and trigonometry at a young age so that he could grasp the concepts of rocketry. He joined the German army to develop missiles at the age of twenty.  The V-2 ballistic missile is sometimes considered the brainchild of Von Braun’s early career, although many of the components were based on the work of American physicist Robert H Goddard. The V-2 launched against London on September 7, of 1944. Von Braun primarily studied rockets for the purpose of space travel, and after the attack on London was quoted to say “the rocket worked perfectly except for landing on the wrong planet.”  Von Braun, who had been personally promoted by Hitler, came under suspicion of sabotage and intention to join the Allies. The rocketeer was overheard expressing regret about the war and the violent use of their scientific talents, and he was detained for several weeks without knowledge of his crime. After some deliberation, Hitler conceded to release Von Braun as long as was useful to their cause.  Yet other factors began to spell doom for the Nazi regime, and Von Braun began to prepare for an Allied victory. Fully aware of the infamous brutality of Soviet forces, Von Braun and his assistants chose to surrender to the United States.  After the Allied Forces captured the V-2 complex, the United States transported Von Braun and other German engineers to American soil through a program called Operation Paperclip. Von Braun was one of several officials who were expunged of Nazi involvement and given new employment histories. Many Americans protested this move, namely Albert Einstein, who had been Von Braun’s childhood idol.  The German engineers had to grow accustomed to the American way of business: they had indulged in all Nazi accommodations, but the United States neglected their living conditions and scientific freedom. Despite these hindrances, Von Braun helped to design the Jupiter-C rocket that sent the first satellite of the West, Explorer 1, into orbit in 1958.  As the Soviet space program grew, Von Braun struggled to earn the trust of his American hosts and improve their lacking interest in rocketry, but their focus was ever on his questionable history rather than his visions of space exploration. To this day, the extent of his loyalty to the Nazi party is still debated, though his contribution to the science of rocketry is unquestionable.

Sources

1. Brzezinski, Matthew. Red Moon Rising: New York, New York, Times Books, Published 2007.

2. Wright, Mike D. MSFC History Office: Dr. Wernher von Braun, at http://history.msfc.nasa.gov/vonbraun/bio.html.

Telescopic Topic #4 – The Extraterrestrial Traveler

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Iron Meteorite found in Sibera Image Credit: Raab

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The Extraterrestrial Traveler by Joshua Rice

What do you think of when you hear the word meteorite? A giant space rock that is crashing into Earth? Well you are close! A meteorite is an extraterrestrial rock that enters Earth’s atmosphere, falling to the surface of our planet. It may be a giant rock when it starts crashing into Earth, but it begins to burn up when it hits Earth’s atmosphere. By the time it actually hits the ground, it is usually quite small. But what exactly are meteorites and where do they come from? Often people think of meteorites as just space rocks, but this is only partially true. There are several different types of meteorites, with one of the most common being iron meteorites. Iron meteorites are composed of about ninety percent iron, with nickel and some other trace elements. This type of meteorite may even have trace amounts of precious metals in it, such as iridium, gallium, or even gold.

By now perhaps you are wondering where these meteorites came from. Well from what scientists can tell, iron meteorites originate from the depths of our Solar System. Specifically, iron meteorites come from the cores of very small, young planets. When our Solar System was just beginning, there was an abundance of small planets forming with iron and nickel cores. Unfortunately, the early stages of our Solar System were very unorganized. This resulted in many collisions that occurred between the different young planets, tearing them apart. These pieces of small, young planets from catastrophic collisions are what make up the iron meteorites we see today. In fact, because these meteorites are from the early stages of planet formation, iron meteorites offer scientists a great snapshot of the early stages of planetary development in our Solar System. So the next time you encounter a meteorite, remember that not all meteorites are created equal!

 

Sources:

Notkin, Geoffrey. Iron Meteorites, The Heart of Long-Vanished Asteroids [Internet]. Geoffrey Notkin; [cited 2013 Mar 15] .

Yang, Jijin , Goldstein, Joseph I, Scott, Edward  RD. 2007. Iron Meteorite Evidence for Early Formation and Catastrophic Disruption of Protoplanets. Nature.  446:888-891.

Bottke, William F, Nesvorny, David , Grimm, Robert E ,Morbidelli, Alessandro , O’Brien, David P. 2006. Iron Meteorites as Remnants of Planetismals Formed in the Terrestrial Planet Region. Nature. 439: 821-824.

Telescopic Topics #3 – Naming of planets and moons

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The Galilean Moons of Jupiter Image Credit: NASA Planetary Photojournal

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Astronomy Name Game by Jamie Binkley

Ever wonder how the planets and moons are named? Who chooses the names and how do those titles they become official?

We can trace the history of the names of planets, moons, craters, asteroids, comets, and their features beginning in the late 1500’s when naming of astronomical bodies was unregulated and disorganized to today where we have an official organization dedicated to titling space objects in a systematic, traditional manner.  To identify, remember and talk about things, we give them names. In the beginning of our discoveries in space, scientists historically were responsible for the naming of such objects. The names chosen had a common theme and were first based on Roman mythology and later Greek mythology as well.  What happened when two astronomers discovered the same object and name them differently? This indeed occurred with four moons of Jupiter when Galileo and Simon Marius each dubbed the moons separately. In the end, it was Marius’ choices (suggested by Johannes Kepler) which we call them today – Io, Europa, Ganymede and Callisto.  Problems such as double naming were eliminated in 1919 when the International Astronomical Union (IAU) was founded. In the inaugural meeting, members created a committee to name planets and satellites which is now known as the Working Group for Planetary System Nomenclature. As of November 2012, they have officially named over 15,000 objects in space.  The IAU bases the nomenclature on a variety of topics – themes, Latin, traditional, historical people, musicians, writers, poets, scientists. Only comets and asteroids may be named after a person living; however, they may not be a political figure.

Today, the IAU officially brands names for planetary objects and satellites as well as other astronomical objects chosen carefully based on themes and tradition. They transformed the nomenclature of our solar system from chaotic and disorganized to regulated and orderly.

Sources:

1. Shatner’s mission: To name Pluto moon after Vulcan. South Florida sun-sentinel. 2013 February 23.

2 Faircloth K. Don’t You DARE Try to Name Pluto’s Moons After Some Internet Nonsense. New York Observer, The (NY).

2013 February 11.

3 Lopes R. From Handel To Hydra: Naming Planets, Moons & Craters. Sky & Telescope. 2012 November:28-33.

4 Nature. The name game. Nature. 2012 August 23;488(7412):429.

Telescopic Topics #2 – The woman who looked up

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Caroline Herschel, Age 92 from original lithograph by George Muller

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The woman who looked up by Allison Oats

Famous and important women can sometimes seem to be hard to find in history.  However, there are an abundant amount whether their role is primary or secondary.  One such historic woman is Caroline Herschel.  She is an important woman because of her contributions and dedication to the continuation of astronomy. Caroline Lucretia Herschel was born on March 16, 1750 in Hanover.  Her father Issac Herschel gave her basic lessons in mathematics, music, and French.  Caroline, along with her brother William, was musically talented and they both developed a passion for astronomy.  After her father died in 1767, she moved to England to live with her brother William.  She soon became immersed in her brother’s obsession.  They built a huge telescope to help them view everything the sky had to offer. William would call out what he saw in the night sky and Caroline would record and catalogue it.  In 1781, William discovered the planet Uranus.  Caroline’s research impressed King George III so much that she was eventually given money by his majesty to continue her research as an employee to the court.  Caroline is credited with the discovery of eight comets and she submitted a new index to Flamsteed’s Observations of the Fixed Stars adding 560 stars which had not been included in the previous edition.  She received honorary membership of the Royal Society of England in 1835 and was the first of two women to do so.  She received other honors and medals from the Irish and the King of Prussia.  In 1889 an asteroid was named 281 Lucretia in her honor and a lunar crater was named C-Herschel as well.  Caroline Herschel is irreplaceable in the history of astronomy.  Her dedication helped astronomers like her brother and young nephew to excel in their field and she herself was a remarkable astronomer.  She had the respect of her male counterparts at home and abroad and proved that, even though she came from humble beginnings and had the disadvantage of being a woman during her time, she could make a great difference.  Caroline Herschel was a role model around the world and inspired future generations of women to reach for the stars.

Sources:

Ogilvie, Marilyn Bailey.  Caroline Herschel’s Contributions to Astronomy.  Annals of             Science, 32.  1975: 149-161.

Hoskin, Michael.  Caroline Herschel: ‘the unquiet heart.’  Science Direct. 2005.  Volume         29 (Issue 1).  22-27.

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