Aquarius Stream

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The Aquarius Stream is a stellar stream located in the Milky Way Galaxy. It is so named because most of the stars in the stream lie in the direction of the Aquarius constellation. At its nearest point it is about 2000 light years from Earth; at its farthest it is about 30,000 light years away. It is the closest stellar stream to Earth yet found, and the youngest, having formed about 700 million years ago. The stream was discovered in late 2010 by a team of astronomers involved in the RAdial Velocity Experiment (RAVE) survey led by New Zealander Mary Williams. [1] [2]

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Aquarius is an equatorial constellation of the zodiac, between Capricornus and Pisces. Its name is Latin for "water-carrier" or "cup-carrier", and its old astronomical symbol is (♒︎), a representation of water. Aquarius is one of the oldest of the recognized constellations along the zodiac. It was one of the 48 constellations listed by the 2nd century astronomer Ptolemy, and it remains one of the 88 modern constellations. It is found in a region often called the Sea due to its profusion of constellations with watery associations such as Cetus the whale, Pisces the fish, and Eridanus the river.

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<span class="mw-page-title-main">Parsec</span> Unit of length used in astronomy

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<span class="mw-page-title-main">Magellanic Clouds</span> Two dwarf galaxies orbiting the Milky Way

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<span class="mw-page-title-main">Sagittarius Dwarf Spheroidal Galaxy</span> Satellite galaxy of the Milky Way

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<span class="mw-page-title-main">Sagittarius A*</span> Supermassive black hole at the center of the Milky Way

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<span class="mw-page-title-main">Messier 2</span> Globular cluster in the constellation Aquarius

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<span class="mw-page-title-main">Milky Way</span> Galaxy containing the Solar System

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<span class="mw-page-title-main">Virgo Stellar Stream</span> Stellar stream in the constellatiion Virgo discovered in 2005

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In astronomy, the Arcturus moving group or Arcturus stream is a moving group or stellar stream, discovered by Olin J. Eggen (1971), comprising 53 stars moving at 275,000 miles per hour, which includes the nearby bright star Arcturus. It comprises many stars which share similar proper motion and so appear to be physically associated.

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<span class="mw-page-title-main">UDF 2457</span> Star in the constellation Fornax

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S5-HVS1 is an A-type main-sequence star notable as the fastest one detected as of November 2019, and has been determined to be traveling at 1,755 km/s (3,930,000 mph). The star is in the Grus constellation in the southern sky, and about 29,000 light-years from Earth. According to astronomers, S5-HVS1 was ejected from the Milky Way galaxy after interacting with Sagittarius A*, the supermassive black hole at the center of the galaxy. It is possible that it was originally part of a binary system that was tidally disrupted by the supermassive black hole, causing it to be ejected. If this is the case, that it was flung out of the galaxy by the central black hole, it is then the first example of a star that has undergone the Hills mechanism.

References

  1. Galaxy "Crumbs" Found in Milky Way—Proof of Recent Feeding National Geographic, Feb 7, 2011
  2. Chug, Kiran (16 February 2011). "Kiwi astronomer 'in orbit' over find". The Dominion Post . Retrieved 16 September 2011.