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The galaxy NGC 5866 appears practically edge-on to our line of sight. A clear dust lane divides the galaxy into two halves. The galaxy, if viewed face-on, would look like a smooth flat disk with few spiral arms. A blue disk of hot young stars runs parallel to the dust lane. Tim large central bulge is reminiscent of an elliptical galaxy. This is an example of a lenticular galaxy, and lies in the direction of the constellation Draco, 44 million light-years away. Image courtesy NASA,...

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Multiple Galaxy Mergers Continue in Milky Way The Sloan Digital Sky Survey continues to produce ground-breaking results as more data is analyzed. Two results announced relate to our own Milky Way, revealing a far more complicated picture of our home galaxy than previously thought. In the first result, newly found streams of stars criss-crossing large swaths of the northern sky represent the trails of satellite galaxies that have previously merged with the Milky Way. This so-called Field of...

Meeting

IT'S AMAZING I've found it invaluable. Inspirational. These are some of the comments from first timers and seasoned delegates at the 209th meeting of the American Astronomical Society (AAS), held from 510 January 2007 at the Washington State Convention and Trade Center in Seattle, Washington. The biennial gathering was held jointly with the Association of Physics Teachers (AAPT), bringing over 2,200 delegates from around the country. From particle physics to flying on the space shuttle, from...

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Above Idealized light curves (plots of brightness vs. time) of Type Ia supernovae. Studies of these objects in relatively nearby galaxies show that most of them have nearly the same peak luminosity, the intrinsically more powerful supernovae take longer to brighten and fade (say, from half of their peak brightness back down to half of their peak brightness) than the less powerful ones. By measuring the light curve of a distant supernova and comparing with the known relationship between...

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A Chandra observation of the supernova remnant 3C58 showed that the central pulsar is surrounded by a bright torus of X-ray emission, as with the Crab Nebula and Vela pulsars. An X-ray jet erupts in both directions from the center of the torus, and extends over a distance of a few light years. Further out, an intricate web of X-ray loops can be seen. Image courtesy NASA CXC SAO P.Slane et al. reaching explosive activity generated by supermassive black holes. Galaxy clusters are the largest...

April 2006

Galaxies Align Forming String of Beads Astronomers have found that spiral galaxies are not randomly oriented in space. They appear to be preferentially aligned. The dramatic results come from a careful study of two huge galaxy surveys, the Sloan Digital Sky Survey and the Two-Degree Field Galaxy Redshift Survey, combined with precise locations of known voids, large spaces lacking in bright galaxies. Left 4 April 2006. The spin axes of spiral galaxies appear to be aligned with the large scale...

June 2006

2mi207b Planet

The Thirty Meter Telescope proceeds to a detailed design stage following successful completion of its conceptual design review by an independent panel. Pushing the limits of engineering design, the TMT will carry a mind-boggling 738 individual 1.2 meter mirror segments spanning 30 meters, offering nearly ten times the light collecting power of existing telescopes. The plan is for first light to occur in early 2016, three years after the expected launch of the James Webb Space Telescope (JWST)....

Debris Disks

The Zodiacal Light Our Own Debris Disk IN OUR own Solar System primitive bodies, such as comets and asteroids, are continually being eroded, releasing puffs and tails of debris, seeding interplanetary space with tiny dust grains. Born within the thin plane containing most of the solid mass orbiting the Sun, the trillions of dust grains form a tenuous, flattened cloud called a circumstellar disk. If gravity were the only force acting on these grains, then they would continue to orbit the Sun....

December 2006

Do Galaxies Follow Darwinian Evolution VLT Survey Provides New Insight into Formation of Galaxies The Very Large Telescope VLT has spent some of its valuable observing time over the past three years studying over 6,500 galaxies at varying distances from Earth, all the way out to 9 billion light-years. Looking at the huge atlas of galaxies generated by the VLT, astronomers have come to some interesting conclusions relating to a vibrant topic in current research - the evolution of galaxies. Our...

January 2007

X-Ray Evidence Supports Possible New Class of Supernova The two largest orbiting X-ray observatories, NASA's Chandra and ESA's XMM Newton, have uncovered evidence for a new class of supernova explosion. The evidence comes from data obtained from two supernova remnants, DEM L238 and DEM L249, until now thought to be the product of normal Type Ia supernovas, caused by the explosion of white dwarf stars. While the tell-tale large signal of iron is present in both remnants, the hot gas is brighter...