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It’s been a little while since our last news dispatch and in the interim there has been a lot of really exciting and surprising news coming down off the wire. This edition we will cover Spitzer’s amazing look into the ever stranger comet Holmes, research is showing that massive black holes were common in the early cosmos and astronomers have discovered asteroid belts and hints of unseen planets in one of our closet neighbors, Epsilon Eridani. In addition studies are showing that young terrestrial planets stay hotter for much longer than previously thought and the deepest ground based ultra-violet image has been taken, showing a stunning sea of far off galaxies. So without further ado…….
Peeking Inside Comet Holmes: Some of you may remember the outburst of comet Holmes back in November 2007; it was a surprise event that increased the brightness of the comet by a million fold, and overnight at that. The event wasn’t well understood then and is still causing trouble for astronomers eager to  | Anatomy of a comet.
Credit: Anatomy of a Comet: Credit:
NASA/JPL-Caltech/XMM/NTT/MPIA |
understand why this happened when it did. Using the Spitzer infra-red space telescope astronomers imaged the comet in great detail in both November of 2007 and March of 2008 and what they found was curious to say the least. The researchers discovered that by the round of second observations (March) fine grains of silicate dust had scattered and only larger particles remained; those that were too large to be blown away by the solar pressure. In the November observations streamers were seen coming from the comet and they were directed away from the Sun, which is normal due to the factor of solar radiation that usually produces the directional tail that comets are usually famous for, but in the March observations even though the comet had moved its position relative to the Sun the streamers still faced in the same direction, which was not directly opposite the Sun and a very curious observation. Astronomers are still at a loss to explain the shape of the comet’s shell and according to Jeremie Vauballion, a researcher on the comet Holmes case, they “have never seen anything like this comet before.” So clearly there is much to be done and understood before anyone can answer the questions that these observations of Holmes bring to the fore. Stay tuned for more information and updates. To read more on this and see our original source visit the following link; http://www.spitzer.caltech.edu/Media/releases/ssc2008-18/release.shtml Super-Massive Black Holes are Nothing New: Using the Submillimeter Array, which is comprised of eight linked radio antennas located in Hawaii, a team of astronomers have found that super-massive black holes were common in the very early universe. The observations were originally of one galaxy that had a specific radio signature  | Two interacting galaxies, though not the
ones refered to in the article. Image taken
by the Hubble space telescope.
Credit: NASA,ESA and the Hubble Heritage
Team (STScI) |
that is telling of an active quasar in its core and it had been assumed that what the astronomers saw was a star birth event, but more recent observations have revealed that the star birth isn’t taking place in the originally seen galaxy at all. Dubbed 4C60.07, the galaxy has a companion and it is in this previously unseen companion that the star birth is taking place. The observations of these early galaxies, approximately 12 billion light years away, showing galaxies that are each about the size of our own milky way that hold super-massive black holes at their cores. Astronomers are earnestly trying to understand how the large abundance of black holes in the early universe came to be, it is necessary for our cosmological models to explain such observations and will tell us much about the formation and evolution of galactic structures in the early universe. The work is vital because if you have a model that can’t explain what you see than you are in trouble and understanding how and when black holes came onto the scene is a large part of that model. Stay tuned for more about this intriguing subject. To read more and to view our original source, follow the link; http://www.scitech.ac.uk/KE/Ind/SubArrBH.aspx Epsilon Eridani; a triple belt system: As seen from the surface of the Earth, on a clear night, the star Epsilon Eridani seems no different from all the other points of light flung across the sky, for it sits among its brethren as unassuming as any, but around this particular point of light astronomers have found a triple-ring system, that in  | Illustration of the Episilon Eridani System.
Credit: NASA/JPL--Caltech |
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many ways resembles our own solar system or at least the way it might have looked in its young age. Epsilon Eridani is found in the Eridanus constellation and is around 10.5 light years away (or about 63 trillion miles) from the Earth and is a relatively young star, only about 850 million years old. The star itself is somewhat smaller and cooler than our own, in the midst of stabilizing its system and is still in the process of forming planets. The observations of this system have shown it to have two asteroid belts, one in the inner system (which very much resembles our own asteroid belt) and one in the outer system, as well as an icy ring that is found in the far reaches of the system. The inner ring is itself much like our own asteroid belt, with similar distance and similar amounts of material, the second ring is about where Uranus is in our own system and contains about as much material as is in our own Moon. The third, outer and icy ring resembles our own Kuiper belt. One of the more interesting things about all these rings is that they are separated by space in which planets are believed to be forming, helping to clear the rings and establish them through their gravitational sweeping. The astronomers are saying that three planets in this system that have masses between Neptune and Jupiter would explain observations very well and this is very exciting. The nature of this system is very close to what we believe our own used to be so it is in some sense likely that the system will evolve very much like our own, which is very exciting in itself. Another interesting tidbit that all you Star Trek fans may find interesting is that Vulcan, the home planet of Mr. Spock was said to be around this very star, so Vulcan, in some minor sense may be a reality. To read more on this story and to see our original source visit the following link: http://www.cfa.harvard.edu/press/2008/pr200822.html Young, Rocky Planets Keep Their Heat: Work done by an MIT planetary scientist, Elkins-Tanton, is showing that young terrestrial planets (rocky worlds) may stay hotter for much longer than previously thought allowing enough radiation to improve detection against the background light of their parent-star. The work has been achieved through computer modeling of the geological processes that take place in forming worlds, which are two fold; one is the initial heating of the planet through the radioactive decay of material inside the planet and by collisions of tons of external material with the body, and two what is called the “overturn” process which consists of the cooling and sinking of heavier materials from the surface toward the core, which in turn churns up the hotter material. The reason this data is so important and exciting is that, if right, it gives us a much longer window in which to detect small rocky worlds directly by the heat that they are giving off. Once equipment improves this could be a vital method for such detection. To read more on this subject and to see our original source follow the link below: http://www.sciencedaily.com/releases/2008/10/081015144137.htm Deepest Ground Based U.V. Image: The European Organization for Astronomical Research in the Southern Hemisphere has released the deepest image in the ultra-violet ever taken from ground based observations. Using in part The Very Large Telescope located in the high desert of northern Chile the image is of a particular  | The Chandra Deep Field South seen
in U-band light. Credit:ESO |
part of the sky called the Chandra Deep Field South, which is one of the most observed parts of the sky, having been observed in almost every wavelength. The image itself is filled with galaxies of all different shapes and sizes and is composed of over 55 hours of observations and more than 27 million pixels. Some of the galaxies detected are a billion times fainter than the human eye can see unaided and it shows galaxies that are located in the very early universe when the cosmos was only around two billion years old. The image was taken mainly in the U-band, which is right between the visible range and the ultra-violet, making it an image taken at the edge of detect ability for ground based observations. Taking an image in this range of light is very hard from the ground because of the Earth’s atmosphere, which is not transparent to all wavelengths of light, any more into the u.v. and it would have needed to be taken from space. The value of this image is found in its depth and variety and will aid astronomical study of the formation and evolution of galaxies in the Universe. Except for a few foreground stars, each one the points of light in this image is an entire galaxy that contains hundreds of billions of stars which in and of itself should be impactful in a purely aesthetic sense. Along with the Hubble Ultra-Deep field, this image shows us the immensity and awesome breadth of the Cosmos of which we are so small a part. The stark beauty of this picture serves to remind us of our position in our Universe and if nothing else underscores the importance of scientific research, for it helps us to understand the story of our origins and that is something that we ought to never take for granted. To see more on this image and to see our original source follow the link below: http://www.eso.org/public/outreach/press-rel/pr-2008/pr-39-08.html |
