|Designation|| Messier 16|
|Right ascension||18h 18m 48s|
|Declination||-13° 49′ 0″|
|Type of object||Emission nebula|
|Magnitude|| Apparent Mag: +6.0|
Absolute Mag: -8.21
|Distance from Earth||7,000 ly|
|Proper motion|| RA: 0.62 mas/yr|
The Eagle nebula, also known as the Star Queen nebula, is a diffuse nebula in the constellation of Serpens. Specifically, it is an emission nebula that also contains an open star cluster. It is known for containing the Pillars of creation, famously photographed by the Hubble Space Telescope in 1995. The nebula itself is also classified as IC 4703 and the open cluster it houses is classified as NGC 6611. Its name is derived from its appearance as an eagle with outstretched wings.
The nebula was discovered by Charles Messier in 1764 during his search for comet like objects, though the star cluster was discovered two decades earlier in 1745/1746 by Philippe Loys de Chéseaux. Messier found the nebula independently of Chéseaux, as Chéseaux only described a collection of stars. First photographed in 1895, its name as the Star Queen nebula was coined by Robert Burnham, Jr., as the middle pillar in the nebula reminded him of the outline of the Star Queen.
Properties and Structure
The nebula has an estimated mass over 12,000 times greater than the Sun. The nebula itself is 55 light years wide and 70 light years tall, while the cluster it contains has a radius of around 15 light years.
The open cluster M16 contains is home to about 460 stars. As the cluster is irregular, it is classified as a type c cluster. It contains large numbers of class O and B stars, O stars extremely large and luminous; they are perhaps 80 more massive than the Sun and at least a million times brighter. Their high temperature means that they also produce copious amounts of x-rays as well as ultraviolet radiation that illuminates the nebula.
Pillars of Creation
The Pillars of Creation are a group of three huge gas pillars found in the Eagle nebula. It was named after an image by the Hubble Space Telescope in 1995. Stars contained within the pillars are a strong source of ultraviolet radiation and stellar wind that is slowly blowing the pillars apart. These stars are extremely hot, with temperatures of over 30,000 k, six times hotter that the Sun.