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Globular Clusters
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Stars/galaxy News
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Globular clusters, often regarded as the most boring denizens of our galaxy, have just become a lot more interesting. Rogue, hot stars have been discovered inside them. The tens of thousands of stars that make up each globular cluster were all thought to have formed at the same time, with exactly the...
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Milky Way Companions
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Stars/galaxy News
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105
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40042
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Title: Two New Milky Way Companions
Authors: Beth Willman
The researchers discuss the detection limits and current status of a uniform survey of
SDSS I for ultra-faint Milky Way dwarf galaxies; and present the properties of
two new, low surface brightness Milky Way companions...
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The Large Magellanic Cloud
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Art gallery
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52
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34595
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The Small Magellanic Cloud (SMC, upper right), and the Large Magellanic Cloud (LMC).
The SMC is about 210,000 light-years and the LMC about 180,000 light-years away.
At lower left, is the brigh...
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The Small Magellanic Cloud
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Art gallery
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22610
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The Small Magellanic Cloud is a dwarf irregular galaxy named after the Portuguese navigator Ferdinand Magellan[url=http://antwrp.gsfc.nasa.gov/apod/image/0506/SMCHam...
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Milky Way
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Stars/galaxy News
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254
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37033
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A collision between another galaxy and our own 5 billion years ago may have spawned the stars in the outer Milky Way.
Elemental abundance ratios for bright giants in the old, distant open clusters Berkeley 20, Berkeley 21, NGC 2141[/co...
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NGC 5466
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Stars/galaxy News
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2
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2499
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NGC 5466 is a class XII globular cluster in the Boötes constellation. Located 51,800 light years from Earth and 52,800 light years from the Galactic centre, it was discovered by William Herschel on May 17, 1784 and as H VI.9. It is thought to be the source of a stellar stream discovered in 2006. [url=ht...
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Ancient LMC Supernovae
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Stars/galaxy News
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34274
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A team of astronomers has found faint visible echoes of three ancient supernovae by detecting their centuries-old light as it is reflected by clouds of interstellar gas hundreds of light-years removed from the original explosions.
Located in the nearby [url=http://www.geocities.com/am...
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(SN) 1987A
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Stars/galaxy News
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19491
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On February 23, 1987, observers saw a star explode in the Large Magellanic Cloud, (a nearby dwarf galaxy).
At about 169000 light years away, it was the closest seen in the past 300 years; and astronomers have continu... < 1.6 x 10^{-14} ergs/s/cm^2 in the wavelength range 2900-9650 Angstroms for any continuum emitter at the centre of the supernova remnant (SNR). It is likely that the SNR contains opaque dust that absorbs UV and optical emission, resulting in an attenuation of ~35% due to dust absorption in the SNR. Taking into account dust absorption in the remnant, we find a limit of L_opt < 8 x 10^{33} ergs/s. We compare this upper bound with empirical evidence from point sources in other supernova remnants, and with theoretical models for possible compact sources. Bright young pulsars such as Kes 75 or the Crab pulsar are excluded by optical and X-ray limits on SN 1987A. Of the young pulsars known to be associated with SNRs, those with ages < 5000 years are all too bright in X-rays to be compatible with the limits on SN 1987A. Examining theoretical models for accretion onto a compact object, we find that spherical accretion onto a neutron star is firmly ruled out, and that spherical accretion onto a black hole is possible only if there is a larger amount of dust absorption in the remnant than predicted. In the case of thin-disk accretion, our flux limit requires a small disk, no larger than 10^{10} cm, with an accretion rate no more than 0.3 times the Eddington accretion rate. Possible ways to hide a surviving compact object include the removal of all surrounding material at early times by a photon-driven wind, a small accretion disk, or very high levels of dust absorption in the remnant.
Read More (PDF)
Photo of the Large Magellanic Cloud and supernova
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NGC346
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Stars/galaxy News
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12
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10183
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[url=http://www.activeboard.com/forum.spark?forumID=58381&subForumID=150691&action=viewTopic&commentID=3273659]Smal...
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Milky Way magnetic field
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Stars/galaxy News
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0
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1070
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Map of Milky Way's magnetic fields charted In a new study, an international team of scientists pooled their radio observations into a database to produce the highest precision map to date of the magnetic field within our own Milky Way galaxy. Researchers at the Naval Research Laboratory, led by the...
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Smith's Cloud
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Stars/galaxy News
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13
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4994
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With the help of a University of Wisconsin-Whitewater physics professor and two recent graduates, crucial information has been gathered about a giant cloud of hydrogen gas headed toward the Milky Way Galaxy. The information was gathered by Assistant Professor of Physics Robert Benjamin, and re...
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Milky Way's disk
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5
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3407
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Most bright stars in our Milky Way Galaxy reside in a disk. Expand Since our Sun also resides in this disk, t...
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Milky Way Halo
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Stars/galaxy News
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19
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6328
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Using 20,000 stars observed by the Sloan Digital Sky Survey (SDSS-II), an international team of astronomers has discovered that the outer Milky Way is a mix of two distinct components rotating in opposite directions. "By examining the motions and chemical makeup of the stars, we can see that...
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Sagittarius A*
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Stars/galaxy News
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62
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18211
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There is some evidence, though yet unconfirmed, that Sagittarius A*--the supermassive black hole at the Galactic centre--emits its radio waves modulated with a ~100-day period.
What is intriguing abou...
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GLIMPSE360 survey
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Astronomy News
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0
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1339
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Spitzer Space Telescope Surveys the Milky Way's Outback A new survey mission by NASA's Spitzer Space Telescope has turned up treasures aplenty in the outer regions of the Milky Way, where amidst fogs of interstellar chemicals some rare, young and enormous stars are blasting gas out into space. The...
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Natural nuclear accelerators
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Astronomy News
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0
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1220
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Cosmic accelerators discovered in our galaxy by UCLA physicists, Japanese colleague Physicists from UCLA and Japan have discovered evidence of "natural nuclear accelerators" at work in our Milky Way galaxy, based on an analysis of data from the world's largest cosmic ray detector. T...
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Aquarius Stream
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Stars/galaxy News
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3
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2076
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Title: The Dawning of the Stream of Aquarius in RAVE Authors: Mary E. K. Williams, Matthias Steinmetz, Sanjib Sharma, Joss Bland-Hawthorn, Roelof S. de Jong, George M. Seabroke, Amina Helmi, Kenneth C. Freeman, James Binney, Ivan Minchev, Olivier Bienaymé, Rachel Campbell, Jon P. Fulbright, Br...
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Galactic Center
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Stars/galaxy News
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12
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4212
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Title: Can a Satellite Galaxy Merger Explain the Active Past of the Galactic Center? Authors: Meagan Lang, Kelly Holley-Bockelmann, Tamara Bogdanovic, Pau Amaro-Seoane, Alberto Sesana Observations of the Galactic Center (GC) have accumulated a multitude of "forensic" evidence i...
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Milky Way Project
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Astronomy News
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4
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2667
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The Milky Way Project aims to sort and measure our galaxy, the Milky Way. Initially we're asking you to help us find and draw bubbles in beautiful infrared data from the Spitzer Space Telescope. Understanding the cold, dusty material that we see in these images, helps scientists to learn how stars fo...
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Milkyway Carbon monoxide
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Stars/galaxy News
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0
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993
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Carbon monoxide in the cosmos mapped for the first time The Planck space telescope was designed to look at the background glow in the cosmos in an effort to understand how it formed. Coincidentally, scientists have found, it can help spot star-forming regions where carbon monoxide glows brightly d...
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Sagittarius A East
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Cosmology News
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3
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2662
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Title: A Candidate Neutron Star Associated with Galactic Center Supernova
Remnant Sagittarius A East
Authors: Sangwook Park (Penn State), Michael P. Muno (UCLA), Frederick K.
Baganoff (MIT), Yo****omo Maeda (ISAS), Mark Morris (UCLA), George Chartas
(Penn State)...
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Virgo Stellar Stream
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Cosmology News
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0
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1031
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Title: Update on the Nature of Virgo Overdensity Authors: Ana Bonaca, Mario Juric, Zeljko Ivezic, Dmitry Bizyaev, Howard Brewington, Elena Malanushenko, Viktor Malanushenko, Daniel Oravetz, Kaike Pan, Alaina Shelden, Audrey Simmons, Stephanie Snedden We use the Eighth Data Release of Sloan...
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Milky Way circumnuclear ring
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Stars/galaxy News
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1
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1788
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SOFIA Spots Recent Starbursts in the Milky Way Galaxy's Center Researchers using the Stratospheric Observatory for Infrared Astronomy (SOFIA) have captured new images of a ring of gas and dust seven light-years in diameter surrounding the supermassive black hole at the center of the Milky Way, a...
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Central Molecular Zone
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Stars/galaxy News
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2
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1299
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[url=http://en.wikipedia.org/wiki/Central_Molecular_Zone]...
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