High-resolution VLBA imaging of the radio source Sgr A at the Galactic Centre
Article Abstract:
Observations of the compact radio source Sgr A using the Very Long Baseline Array and other radio telescopes bore out previous evidence that Sgr A, located near the Galactic Center, marks the location of a large black hole. Sgr A was imaged at 3.6 and 1.35 centimeter wavelengths and was found to be producing radio emissions that were scattered by electron-density fluctuations along the line of site. These and other findings indicate the presence of a black hole equal to about two times 10 to the sixth power solar masses.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
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Fire burn and cauldron bubble
Article Abstract:
The dust and gas observable in the Milky Way Galaxy's disk contains ruptured shells or 'worm-like' structures that are probably left over from the bubbles of hot gas produced by supernovae or exploding stars. Astronomers B.-C. Koo, C. Heiles and W.T. Reach based this finding on a re-examination of archival observations. This first reliable confirmation that burst or bursting bubbles exist in the Milky Way reinforces the view that supernovae and star clustering have shaped the Galaxy's violent evolution.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1992
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The centre of the Milky Way
Article Abstract:
The shape of the Milky Way galaxy is that of a barred spiral, with the bulge in the center consisting of a stellar bar. Photometric observations reveal the bar, whereas X-ray work shows that a pressure wind escapes the central bar, composed of gas which was pulled into the center. Some of the gas which is drawn into the bar is converging on a dense stellar cluster, indicating that a black hole may exist inside the cluster.
Publication Name: Nature
Subject: Zoology and wildlife conservation
ISSN: 0028-0836
Year: 1993
User Contributions:
Comment about this article or add new information about this topic:
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