NGC 4665, also catalogued as ''NGC 4624'' and ''NGC 4664'', is a barred lenticular or
spiral galaxy
Spiral galaxies form a class of galaxy originally described by Edwin Hubble in his 1936 work ''The Realm of the Nebulae''Virgo. It is a member of the
Virgo II Groups
The Virgo II Groups, also known as the Virgo II Cloud, Virgo Southern Extension, or the Virgo S Cloud, are a series of at least 100 galactic clusters and individual galaxies stretching approximately off the southern edge of the Virgo Supercluster ...
, a series of galaxies and galaxy clusters strung out from the southern edge of the Virgo Supercluster. It is located at a distance of circa 60 million
light year
A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...
s from Earth, which, given its apparent dimensions, means that NGC 4665 is about 75,000 light years across. NGC 4665 lies 2 and 3/4 degrees east-south east of
Delta Virginis
Delta Virginis (δ Virginis, abbreviated Del Vir, δ Vir), formally named Minelauva , is a star in the zodiac constellation of Virgo (constellation), Virgo. With an apparent visual magnitude of 3.4, this star is bright enough to be seen w ...
and 50 arcminutes southwest of
35 Virginis
This is the list of notable stars in the constellation Virgo, sorted by decreasing brightness.
See also
*List of stars by constellation
References
*
*
*
*
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{{DEFAULTSORT:List of stars in Virgo
*List
Virgo
Virgo may refer to:
*Virgo ( ...
. It can be viewed through a moderately sized telescope with 23x magnification, forming a pair with an 11th magnitude star 1.5 arcminutes southwest. It is part of the Herschel 400 Catalogue.
Observation history
It was discovered by William Herschel on February 23, 1784, however, he noted a location 10 arcminutes off the galaxy, where there is no object. It was observed by William Herschel again on April 30, 1786, noting the correct coordinates, and he misidentified it as another nebula. The fact that they are the same object was noted by John Louis Emil Dreyer in 1912 in the corrections of the New General Catalogue. It was also recorded independently on April 9, 1828 by
John Herschel
Sir John Frederick William Herschel, 1st Baronet (; 7 March 1792 – 11 May 1871) was an English polymath active as a mathematician, astronomer, chemist, inventor, experimental photographer who invented the blueprint and did botanical wor ...
.
Physical characteristics
NGC 4665 has a luminous, slightly elliptical bulge and a prominent
bar
Bar or BAR may refer to:
Food and drink
* Bar (establishment), selling alcoholic beverages
* Candy bar
* Chocolate bar
Science and technology
* Bar (river morphology), a deposit of sediment
* Bar (tropical cyclone), a layer of cloud
* Bar (u ...
with high surface brightness. The isophotes appear boxy at the end of the bar. The total bar length is estimated to be near 3 kpc. The bar is slightly twisted, turning near 12 degrees along its axis. Two diffuse, faint arms emerge from each side of the bar and form a pseudoring. The surface brightness of the arms is higher near the bar. The southern arm appears a bit stronger. An arch feature is observed at the east side of the galaxy that could be a partial outer dusty ring. The outer isophotes are elliptical. The total mass of molecular gas is less than .
NGC 4665 belongs to the NGC 4636 group. Other members of the group include NGC 4457,
NGC 4586
NGC 4586 is a spiral galaxy located about 50 million light-years away in the constellation Virgo. The galaxy was discovered by astronomer William Herschel on February 2, 1786. Although listed in the Virgo Cluster Catalog, NGC 4586 is considered ...
Messier 61
Messier 61 (also known as M61 or NGC 4303) is an intermediate barred spiral galaxy in the Virgo Cluster of galaxies. It was first discovered by Barnaba Oriani on May 5, 1779, six days before Charles Messier discovered the same galaxy. Messier h ...
and their groups form the southern boundary of the Virgo cluster. It can be difficult to determine which galaxies belong to which group, especially around the southern edge of the Virgo cluster where there is a confusion of galaxies at different distances.