Seyfert's Sextet is a
group of galaxies about
190 million light-year
A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by the International Astr ...
s away
[ ] in the
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The first constellati ...
Serpens
Serpens () is a constellation in the northern celestial hemisphere. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the 88 modern constellations designated by the International Astronomical Union. It ...
. The group appears to contain six members, but one of the galaxies,
NGC 6027d, is a background object (700 million light years behind the group) and another "galaxy,"
NGC 6027e, is actually a part of the tail from galaxy
NGC 6027. The
gravitational interaction among these galaxies should continue for hundreds of millions of years. Ultimately, the galaxies will merge to form a single giant
elliptical galaxy
An elliptical galaxy is a type of galaxy with an approximately ellipsoidal shape and a smooth, nearly featureless image. They are one of the three main galaxy morphological classification, classes of galaxy described by Edwin Hubble in his Hub ...
.
Discovery
French astronomer
Édouard Stephan
Édouard Jean-Marie Stephan (31 August 1837 – 31 December 1923) was a French astronomer. His surname is sometimes spelled Stéphan in some literature, but this is apparently erroneous.
He was born in Sainte Pezenne (today one of the districts o ...
discovered
NGC 6027 on 20 March 1882, but he was unable to resolve the individual galaxies in the group.
The group members were discovered by
Carl Keenan Seyfert using photographic plates made at the
Barnard Observatory of
Vanderbilt University
Vanderbilt University (informally Vandy or VU) is a private university, private research university in Nashville, Tennessee, United States. Founded in 1873, it was named in honor of shipping and railroad magnate Cornelius Vanderbilt, who provide ...
. When these results were first published in 1951, this group was the most compact group ever identified.
Members
See also
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Wild's Triplet
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Zwicky's Triplet
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Robert's Quartet
Robert's Quartet is a compact galaxy group approximately 160 million light-years away in the constellation Phoenix (constellation), Phoenix. It is a family of four very different galaxies whose proximity to each other has caused the creation of ...
*
Stephan's Quintet and
NGC 7331 Group (also known as the Deer Lick Group); about half a degree northeast of Stephan's Quintet
*
Copeland Septet
The Copeland Septet (also Copeland's Septet, Hickson Compact Group 57) is a group of galaxies in the constellation Leo that includes NGC 3748, NGC 3754, NGC 3750, NGC 3751, NGC 3745, NGC 3753 and NGC 3746. The group was discovered by Brit ...
References
External links
ASAHI Net Free Address Service: Seyfert's Sextet (Galaxy Group in Serpens)
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{{DEFAULTSORT:Seyfert's Sextet
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Serpens