APOD 4.8

I am writing about the launch of the space shuttle Endeavour. This Monday the spacecraft was launched from Cape Canaveral in Florida. It is on a docking mission with the International Space Station. The space shuttle is carrying a variety of detectors for dark matter and antimatter that have strong evidence supporting their existence. This is the second to last space shuttle launch that NASA will conduct as the project is being scrapped because of budget cuts and other factors. This picture clearly shows how large the shuttle is and gives some kind of an idea of how much energy is required to launch this and to get it up to escape velocity, which is about 8 kilometers per second. Overall this picture captures the awesome power that can be harnessed right here on Earth.

Robert Kirshner Biography

Robert Kirshner was born in 1949 and is currently alive. He is a professor at Harvard's College of Astronomy and Clowes Professor of Science at Harvard. At the age of 21 he graduated from Harvard and then studied at Caltech where he received a Ph.D. in Astronomy. He then went on to do post doctoral work at the Kitt Peak ?National Observatory. Kirshner served on several scientific boards and was chairman of the Harvard Astronomy Department for 7 years. In the scientific world he is best known for his work with deep sky objects, mostly supernovae and their remnants. He has written over 200 research papers on these topics and his most famous discovery came about when he was on the "High-Z Supernova Team." Kirshner and his team were studying a large collection of supernovas when they came to the conclusion that the Universe is actually expanding at an accelerating rate, not a decelerating one as would be expected. This discovery implies the existence of dark matter, which until then had almost no evidence in support of it. This discovery was dubbed tbhe science breakthrough of the year for 1998 by Science Magazine. The team also received the Gruber Prize for Cosmology in 2007. Along with this discovery he has also served as president of the American Astronomical Society for 2 years and was awarded the Distinguished Alumni Award in 2004 by Caltech. He has also written a book called "The Extravagant Universe" and is currently teaching Science A-35 at Harvard for undergraduates.

Robert Kirshner Bibliography

Kirshner, Robert P. "Robert P." Harvard University. Harvard. Web. 16 May 2011. <https://www.cfa.harvard.edu/~rkirshner/>.

 

"Robert Kirshner." Wikipedia, the Free Encyclopedia. Web. 16 May 2011. <http://en.wikipedia.org/wiki/Robert_Kirshner>.

 

APOD 4.7

I chose to write about the panoramic view of the night sky as seen from the Very Large Telescope site in Southern Chile. Many celestial objects can be seen in this image as well as several easily identifiable constellations. The zodiacal light, sometimes called a false dawn, can be seen towards the left of the image. Venus can be seen as a very bright sphere of light while Saturn can be seen as a slightly fainter one. The constellations are also much easier to identify here because there is almost no light pollution. Among these constellations are Orion, Leo, and Hydra. The band of the Milky Way can also be seen as it stretches across the sky in a semicircle.

APOD 4.6

I chose to write about the Farther Along picture, which depicts the various satellites that have left our solar system and where they are relative to the Sun. The farthest one was launched over 30 years ago and is over 17.5 billion kilometers from the Sun, however this is only slightly more than 16 light hours. The closest stars are several light years, so at this speed it would take millenniums to reach even these close ones, however they are able to reach the outskirts of our solar system and continue their journey to reach interstellar space.

APOD 4.5

Today I chose to write about The Antennae, which is actually two very large galaxies that are colliding. This celestial event is taking place about 60 million light years away towards the constellation Corvus the Crow. This collision, unlike many on Earth, takes hundreds of millions of years to occur. During this time the massive amounts of molecular gas collide which creates very large areas of star formation. Long trails of gas can also be seen in this picture, which are the result of the combining tidal forces and gives this event the name The Antennae.

APOD 4.4

This photo is about M101, which is a massive spiral galaxy that lies about 25 million light years away in the constellation Ursa Major. The sheer size of this galaxy is breathtaking, it is over twice the size of our own Milky Way Galaxy, or about 170,000 light years across. The amount of stars that our contained in this galaxy is equally astounding as it contains many more stars than our own and therefore greatly increases the possibility that it contains planets that are suitable to life or perhaps even planets that already have life forms on them. Galaxies such as this one provide much hope that there could be life other than our own.

APOD 4.3

Today I chose to write about the far side of the Moon because it is something that is astronomically very close to us, yet has been seen by very few people. Because the Moon is locked in a synchronous orbit with the Earth only one side of the Moon can ever be seen from Earth and it is this side that almost everybody is familiar with. This picture however shows the other side of the Moon and it is very interesting how much this side varies with the side we can see. There are no lunar maria on this side, but instead it is covered with a massive amount of craters and appears very rough. Overall it is very interesting how much the Moon can vary simply by looking at one side or another.

Zooniverse

I have been doing planet hunters on Zooniverse for the last several days. So far I have found 2 stars that have been identified as stars of interest and are among the most likely candidates to have planets orbiting them. Looking through the data is very interesting, especially trying to figure out why some of the light curves happen the way they do, and seeing the variable curves of stars in binary systems.

APOD 4.2

This week I chose to write about M74, which is a massive spiral galaxy that is about 32 million light years away. This galaxy is positioned so that it is almost face on with our own, and so the many spirals of it can be seen very well. This galaxy is estimated to have about 100 billion stars in it, which is much larger than our own. A merge between this and a nearby galaxy can also be seen as the smaller galaxy is sucked into M74's core. Furthermore, the idea that when we see this galaxy we are actually looking 32 million years into the past is astounding, because if somebody were to look at earth from this distance they would see it without humans, but with dinosaurs and other extinct creatures. This is why I chose to write about M74 this week.

APOD 4.1

Today I am writing about Island Universe NGC 5584. This is a spiral galaxy similar to our own Milky Way, but it has several interesting features. Among these features are a recently exploded Type I Supernova and over 250 Cepheid Variable Stars. Other amazing facts about this galaxy is its size, which is over 50,000 light years, and its distance which is over 72 million light years away. Another interesting fact about this galaxy is that it was used as data for part of a recent study which helped to improve the accuracy of the Hubble constant, which states how fast the Universe is expanding. Even more amazing than this is that this study actually supports the theory of dark matter, which so far is the only theory that explains why the Universe is expanding even faster.

Astronomy Night

The first star that I saw was Sirius at about 8 PM shortly after the Sun set. The next 2 were Procyon and Canopus, which are both first magnitude stars and among the brightest in the sky. After it got dark we identified, Orion, Orion's Belt, Canis Major and Minor, the area where Monoceros should be, some stars that were part of Columbus and Lepus, The Big Dipper, Triangulum, Auriga, Hydra, Leo, Gemini, and a few others. We identified Betelgeuse, Bellatrix, Rigel, Castor, Pollux, Sirius, Canopus, Capella, Aldebaron, and the Kids in Auriga. There was also one satellite that we saw that was visible for about 30 seconds. Through the telescopes we saw M42 in Orion and Saturn which was very detailed and the space between the planet and the rings was actually visible. Overall it was a very fun stargaze and we were able to identify a large number of celestial objects.

APOD 3.8

This is a picture of NGC 3628, which is an island universe. It is believed to be a spiral galaxy that is seen on its side. This image shows how thin these galaxies can be, especially when compared to their diameters. This is also an interesting picture because it is about 35 million light years away which is unbelievably far, but is seen in fairly high resolution, which is an astounding achievement. Overall this is an amazing image because it shows an entire galaxy in high resolution that is extremely far away and more than likely harbors some kind of life form due to the very large number of stars, and more than likely planets.

APOD 3.7

This is an image of Cassiopeia A, which is a supernova remnant that appeared about 300 years ago. In this picture, which is a composite of X-ray and visible light. It spans about 11,000 light years across, which is relatively small for a nebula, but it is rapidly expanding because it was recently formed. This image is even more astounding because you can actually see the light from the neutron star. This star is only a few miles across, which means it has very little surface area, but the fact that it can be seen from Earth means that it is extremely bright. Another interesting fact about this neutron star is that it is forming a super-fluid that is frictionless. Nothing on Earth could possibly compare to this material, but that fact that it exists in the Universe is astounding.

APOD 3.6

Today I chose to write about Spiral Galaxy NGC2841, which is a galaxy that is similar to our own in structure. In this picture it is easy to see the center of it and the hundreds of blue regions where thousands of new stars are being formed. The lanes that make up the spirals can also be easily seen which makes this picture even more astounding. The simple colors and shape of this picture are enough to make it simply amazing but the scale is even more unbelievable. This galaxy is about 300,000 light years across. This is an incomprehensible distance and is dwarfs even our own galaxy. This single galaxy probably contains millions of stars many of which have planets orbiting them and therefore poses many new possibilities for life to begin or already exist.

James Keeler Biography

Andrew Sanderson

24 February 2011

Astronomy Honors

Mr. Percival

James Keeler Biography

            James Edward Keeler was born in La Salle, Illinois on September 10, 1857. His most famous contributions to astronomy were that the rings of Saturn are composed of small particles and that there a very large number of spirals among nebulae. His mother, Anna, was the daughter of the governor of Connecticut and his father, William F. Keeler, was a paymaster in the U.S. Navy. Keeler attended high school until his family moved to Florida and then pursued no higher education for a while. He eventually attended John Hopkins University and served as an assistant to physicist, Charles Hastings. He eventually ended up in Allegheny, where he became the first professional astronomer to reside on Mount Hamilton. Here he used a 36 inch refracting telescope equipped with a spectroscope to measure wavelengths of the very bright spectral lines of nebulae. With this data he was able to tell if they were blue shifted or red shifted and therefore able to tell if they were moving towards or away from the Earth. He also discovered wavelengths that didn’t correspond to any transitions that had been observed on Earth. This lead to the idea that nebulae were comprised of something that wasn’t present on Earth, however this turned out to be incorrect as it was the combination of the motion of the atoms and the filtering effects of the nebulae that caused these lines. Shortly after this discovery he married Cora Slocomb Matthews only to take a journey back to Allegheny observatory. Once here he designed his own spectrograph, which allowed pictures to be taken of the spectral lines instead of simply looking at them through a telescope. This invention allowed the spectral lines of stars to be recorded and saved for later times and also to be analyzed much more effectively than they could have with a spectroscope. An example of how much more effective this new invention was is how Keeler used it shortly after its conception. He used was able to obtain proof that the theoretical prediction of James Maxwell that the rings of Saturn were meteoric in nature was correct. Another major discovery of Keeler was the how the number of spiral nebulae, which later turned out to be other galaxies, outnumbered the quantities of any other hazy object in the night sky. He was attempting to design a slitless spectrograph that could be used in conjunction with the 36 inch telescope when he suffered a heart and died at the age of 42 on August 12, 1900. Despite his relatively short life, Keeler was able to make many contributions to modern day astronomy that greatly changed how the universe is viewed.

APOD 3.5

Today I chose to write about the Rosette Nebula because it of how it looks and because it was on today's constellation quiz. It is located in Monoceros about 5,000 light years away and is an emission nebula with an open cluster of stars at its center. This open cluster of stars releases light from all across the electromagnetic spectrum. This light then hits the nebula and is essentially filtered out, certain wave lengths are absorbed and re-emitted in different directions whereas other wavelengths can go through unimpeded. This means that some colors show up brighter than others and the result is this stunning nebula that can be seen relatively easily.

Quarter 3 Astronomer Sources - James Keeler

1. "Keeler, James Edward." Complete Dictionary of Scientific Biography. Vol. 7. Detroit: Charles Scribner's Sons, 2008. 270-271. Gale Virtual Reference Library. Web. 18 Feb. 2011.

2. "Keeler, James Edward (1857-1900)." The Worlds of David Darling. Web. 18 Feb. 2011. <http://www.daviddarling.info/encyclopedia/K/Keeler.html>.

APOD 3.4

I chose to write about the iridescent clouds as seen from the World Highway in Yukon Territory, Canada. These clouds are formed usually around sunrise or sunset. The increased amount of atmosphere that the light must travel through causes the light to get bent. The blue light is scattered the most because it has the shortest wavelength and so it is not seen in this picture. The red end of the visible light spectrum however is scattered very little and manages to travel through the atmosphere almost unimpeded. The end result of this are clouds that have a very reddish or pinkish tint to them. Not only is this is a very astounding meteorological effect but it also looks very amazing, which is why I chose to write about it.

APOD 3.3

This is a picture of the star Zeta Ophiuchi as it pushes through dust and the interstellar medium. I chose to write about this picture for several reasons, the first being that it is relevant to the material being covered in class. Some of the particles that can be seen on the front of Zeta Oph are from the interstellar medium. While not appreciable by themselves, the motion of this star has brought them closer together and in doing so has made them much more visible. Another reason I chose to write about this picture is because of what is occurring in it. In this picture a star that is 20 times more massive than our own Sun is moving at 24 kilometers per second. The force necessary to bring a star of this mass to this speed is extremely high, but the fact that it has occurred is simply astounding and is why I chose to write about this picture.

APOD 3.2

This is an image of the Polar Ring Galaxy NG660. I chose to write about it because it is such a strange type of galaxy. Its massive ring system orbits it almost perpendicular to the spiral, which is a very unpredicted place for it to be. The fact that an entire galaxy can have a ring system is simple amazing, the amount of debris that must be collected for it to occur is gargantuan. The ring system spans about 40,000 light years and there is very few things that could have caused this system to form. One of the most likely hypothesis for this is that another galaxy with a tail of debris passed closely by it and this galaxy captured the tail and formed these rings. Whatever happened to form this ring was truly amazing, this image shows how many possibilities of galaxies are available in the universe and no matter how minuscule the chance of one of the occurring is, it will happen somewhere in the universe.

APOD 3.1

Today I chose to write about Alnitak, Alnilam, and Mintaka because of how unique they are in the night sky. They are the only 3 2nd magnitude stars in the night sky that line up to form an almost perfectly straight line. These stars look astounding in this picture as they are a very bright blue and dwarf our own Sun in comparison to its size. There are also several other unique astronomical sights that are in this picture, such as the Horsehead Nebula and the Flame Nebula. All of these things combine to create a beautiful picture. This is the major reason that this area of the sky is so interesting to look at, there are over 7 bright stars in a very small area along with nebulae and other objects that are fascinating to study.

Fission Astronomy Cast

Fission is essentially the opposite of fusion, in which heavy unstable atoms decay either rapidly or over long periods of time. Carbon 14 is one of the most commonly known isotopes that undergoes fission. It has a half life of about 5,700 years, meaning that it decays to half of its original mass in 5,700 years. The other common kind of process is the rapid process. This process is most widely recognized in bombs. When very heavy, unstable elements rapidly undergo fission they release massive amounts of energy. However, the slow process is the more common form of this as it requires more stable elements, which are more common in nature. Another interesting fact about this process is the idea of a chain reaction. Each time an element undergoes fission it releases neutrons. These neutrons then go on to induce other elements to fission, which then release more neutrons. When there is a certain amount of mass the process becomes self propagating and it is said to have reached critical mass. Fission can also be used to determine the age of stars by determining the half life of a certain element is and figuring out what percentage of it remains. Overall, fission is very important in the universe and has many practical purposes on Earth as well.

Fusion Podcast

This podcast is about nuclear fusion, largely in the center of stars. The core of many stars are extremely hot, over 10,000,000 degrees Kelvin. When the temperature is this high, the particles in the sun, such as hydrogen atoms and electrons, move at extremely high velocities. At these velocities it is possible for the atoms to overcome the repulsive forces of their charges. If 2 hydrogen atoms collide at a high enough velocity they will fuse together and create heavy hydrogen, which is a hydrogen atom with a neutron. This reaction also produces energy on the level of 1-10 MeV along with neutrinos. This heavy hydrogen then collides with another proton and then with another proton to create a helium atom. These reactions release photons with a blackbody spectrum that peaks in the ultraviolet range but also releases photons up to the gamma ray section. If the Sun could be seen outside the Earth's atmosphere it would appear to be a whitish color because it releases all the visible colors, which forms white. The process of fusion also is what keeps the star 'inflated.' Without this energy pushing the outer layers out, then gravity would cause the star to collapse in on itself and possible create a supernova. Nuclear fusion can be used on Earth to create energy, but the problem is that storing the fusion takes more energy than the fusion itself creates, so there is no point to do it. Solving this problem could greatly reduce the energy crisis on Earth and could be used for great benefit to mankind.

Sun Pictures

http://www.lookpictures.net/gallery/Space/1792/Sun-Extreme-Ultraviolet-Imaging-Telescope-Wallpaper/
http://apod.nasa.gov/apod/ap980923.html
http://apod.nasa.gov/apod/image/0702/cmesun_soho_big.jpg
http://spacefellowship.com/news/art21900/map-of-magnetic-field-lines-of-the-sun.html
http://astronomy.neatherd.org/Swedish%20sunspots1.jpg
http://umbra.nascom.nasa.gov/eclipse/images/freds_excellent_eclipse_img.jpg
http://apod.nasa.gov/apod/image/0604/eclipse2006_seip_big.jpg

Friedrich Georg Struve

Andrew Sanderson
Period 3
Due 11 January 2011

Friedrich Georg Struve

Friedrich Georg Struve was born in Germany on April 15th 1793 into a fairly wealthy and well educated family. When he reached the age of conscription he was sent away to live with his brother in Russia. He graduated from the Russian University Dorpat in 1810 with a degree in philology. However, he did not want to pursue a career in this subject, so instead he began to study mathematics, astronomy, and geodesy. He got his doctorate for accurately determining the location of his university’s observatory and then began to teach. He taught for 25 years in which he lectured in math and astronomy. Astronomically, Struve is famous for many things, most notably in his research and observation of double stars, the observation and determination of stellar parallaxes, the distribution of stars in space, the observation of planets, the moon, comets, and auroras. He also created new and better instruments and refined the old ones to get more accurate and reliable measurements and data. One example of these new instruments he created was when he added a meridian circle and a nine-inch refracting telescope, which was the largest at that time, to the observatory. After this he then moved to a newer observatory in St. Petersburg. He was appointed to the position of director of installation and was tasked with getting the best instruments he possibly could. Among the several new instruments he ordered was a 15 inch refracting telescope, which was now the largest one ever made. After this time he observed about 122,000 stars from the North Pole to 15 degrees south declination. Among these stars he discovered 3,112 double stars, which had previously been undetected. He then began to make micro metric measurements of these stars and tried to determine their angular separations and parallaxes. However, because of the age in which he did this and the limits of his instruments, he was unable to determine very many of the parallaxes accurately, as many of them were less than .5”. With respect to the research he did about the distribution of stars, he wanted to determine if there was a statistical dependence between the brightness of stars and their distance. Among the many conclusions of this research, he was able to conclude that the Sun doesn’t lie at the center of our galaxy, but is rather above its plain. Struve also postulated that light traveling through the Universe is absorbed, so that distant stars cannot be seen because the light from them isn’t bright enough to reach Earth, and the value he came up with is still in use today. Struve also did a lot of research in the field of geodesy. He came up with rational methods to figure out the time, latitude, and azimuth of celestial objects. By doing this he was able to eliminate systematic error that plagued the old methods. At the end of his life he was a member of over 40 scientific academies and universities and founded the Russian Geographical Society. He died on November 23, 1864 and was survived by his wife and 12 children, some of whom went on to do notable astronomical research.

APOD 2.8

Today I chose to write about the lunar eclipse on Earth taken by the Mir Satellite. This image is so amazing to look at because it shows how large of an effect the lunar eclipse has on the Earth and it is shocking to see it from this vantage point. The fact that this shadow moved across the Earth at 2000 kilometers an hour is also stunning because when one puts this in perspective to the average speed of a car or airplane it becomes enormously fast, especially considering the mass and volume of the object that causes it.

APOD 2.7

I chose to write about M82 this week because it is one of the strangest looking galaxies that I have seen. Most galaxies that I have seen pictures of have been spiral galaxies, but this one looks like a bow tie with a cigar going through the middle of it. I really would like to know how a galaxy forms in this unique shape. Along with the shape of it, the sheer dimensions amaze me. The filaments themselves extend over 10,000 light years. This number is completely incomprehensible and is simply stunning to think about, which is another reason why I chose to write about M82 this week.

Friedrich Georg Struve Biography Sources

Complete Dictionary of Scientific Biography. Vol. 13. Detroit: Charles Scribner's Sons, 2008. p108-113.

"Struve, Friedrich Georg Wilhelm Von (1793-1864)." The Worlds of David Darling. Web. 05 Jan. 2011. .