Open Cluster NGC 2175 (also known as OCL 476 or Cr 84) is an

open cluster An open cluster is a type of star cluster made of up to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and ...

in the

Orion constellation Orion is a prominent constellation located on the celestial equator and visible throughout the world. It is one of the most conspicuous and recognizable constellations in the night sky. It is named after Orion, a hunter in Greek mythology. It ...

, embedded in a diffusion nebula. It was discovered by

Giovanni Batista Hodierna Giovanni Battista Hodierna, also spelled as Odierna (April 13, 1597 – April 6, 1660) was an Italian astronomer at the court of Giulio Tomasi, Duke of Palma (Palma di Montechiaro). He compiled a catalogue of comets and other celestial object ...

before 1654 and independently discovered by

Karl Christian Bruhns Karl Christian Bruhns (22 November 1830 – 25 July 1881) was a German astronomer. Biography He was the son of a locksmith, and in 1851 went as locksmith and mechanic, first to Borsig, and then to Berlin with the firm of Siemens and Halske. In ...

in 1857. NGC 2175 is at a distance of about 6,350

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 away from

Earth Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...

. The nebula surrounding it is

Sharpless catalog The Sharpless catalog is a list of 313 H II regions (emission nebulae) intended to be comprehensive north of declination −27°. (It does include some nebulae south of that declination as well.) The first edition was published in 1953 with 14 ...

Sh 2-252. There is some equivocation in the use of the identifiers

NGC 2174 NGC 2174 (also known as Monkey Head Nebula) is an H II emission nebula located in the constellation Orion and is associated with the open star cluster NGC 2175. It is thought to be located about 6,400 light-years away from Earth. The nebula m ...

and NGC 2175. These may apply to the entire nebula, to its brightest knot, or to the star cluster it includes. Burnham's ''Celestial Handbook'' lists the entire nebula as 2174/2175 and does not mention the star cluster.Robert Burnham, Jr, ''Burnham's Celestial Handbook'', Dover, 1978, p. 1280. The NGC Project (working from the original descriptive notes) assigns NGC 2174 to the prominent knot at J2000 , and NGC 2175 to the entire nebula, and by extension to the star cluster. Simbad uses NGC 2174 for the nebula and NGC 2175 for the star cluster. NGC2175 CDK Small 03

References

External links

NGC 2175 @ SEDS NGC objects pages
* {{star-cluster-stub 2175 Open clusters Orion (constellation)