Sh 2-54 is an extended
bright nebula 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 origins of the e ...
of
Serpens.
In its core there are many
protostars
A protostar is a very young star that is still gathering mass from its parent molecular cloud. The protostellar phase is the earliest one in the process of stellar evolution. For a low-mass star (i.e. that of the Sun or lower), it lasts about 50 ...
and many
infrared
Infrared (IR), sometimes called infrared light, is electromagnetic radiation (EMR) with wavelengths longer than those of visible light. It is therefore invisible to the human eye. IR is generally understood to encompass wavelengths from around ...
sources; some of these sources, like
IRAS
The Infrared Astronomical Satellite (Dutch: ''Infrarood Astronomische Satelliet'') (IRAS) was the first space telescope to perform a survey of the entire night sky at infrared wavelengths. Launched on 25 January 1983, its mission lasted ten mo ...
18151−1208, are most probably very young high-mass stars.
The older star population in this region has an average age of 4–5 million years, and its components are grouped in the
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 ...
NGC 6604
NGC 6604 is a young open cluster of stars in the equatorial constellation of Serpens, positioned about 1.5° north of the Eagle Nebula (NGC 6611). The cluster was discovered by William Herschel on July 15, 1784. It is located at a distance of 4, ...
.
Sh 2-54 belongs to an extended nebulosity that includes also the
Eagle Nebula
The Eagle Nebula (catalogued as Messier 16 or M16, and as NGC 6611, and also known as the Star Queen Nebula) is a young open cluster of stars in the constellation Serpens, discovered by Jean-Philippe de Cheseaux in 1745–46. Both the "Eagle" and ...
and the
Omega Nebula
The Omega Nebula, also known as the Swan Nebula, Checkmark Nebula, Lobster Nebula, and the Horseshoe Nebula (catalogued as Messier 17 or M17 or NGC 6618) is an H II region in the constellation Sagittarius. It was discovered by Philippe Loys de ...
. The young high-mass stars of this region constitute the Serpens OB1 and Serpens OB2
OB association
In astronomy, stellar kinematics is the observational study or measurement of the kinematics or motions of stars through space.
Stellar kinematics encompasses the measurement of stellar velocities in the Milky Way and its satellites as well as t ...
.
Gallery
Image:Serpent%E2%80%99s_Nebula.jpg, Serpent's Nebula
See also
*
H II region
References
External links
Sky-Map.org – Sharpless Catalogue (from 51 to 60)
{{DEFAULTSORT:Sh 2-54
H II regions
Serpens
054
The Type 054 (NATO Codename Jiangkai I) is a class of People's Republic of China, Chinese multi-role frigate, frigates that were commissioned in the People's Liberation Army Navy Surface Force in 2005. They superseded the Type 053H3 frigates. Only ...
Star-forming regions
Stellar associations