Eta Carinae Nebula
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Eta Carinae Nebula. Image courtesy of ITA. |
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| Observation data: J2000.0 epoch | |
|---|---|
| Type: | Emission |
| Right ascension: | 10h 43.8m |
| Declination: | −59° 52′ |
| Distance: | ~8000 ly |
| Apparent magnitude (V): | +1.0 |
| Apparent dimensions (V): | ??? arcmins |
| Constellation: | Carina |
| Physical characteristics | |
| Radius: | ??? |
| Absolute magnitude (V): | ??? |
| Notable features: | Includes dark nebula Keyhole Nebula |
| Other designations: | NGC 3372 |
| See also: Diffuse nebula, Lists of nebulae | |
The Eta Carinae Nebula (also known as the Great Nebula in Carina, the Carina Nebula, or NGC 3372) is a large bright nebula which surrounds the star Eta Carinae, one of the most massive and luminous stars in the galaxy. The nebula lies at an estimated distance between 6,500 and 10,000 light years from Earth. It is located in the constellation of Carina. The nebula contains multiple O-type stars.
This nebula is one of the largest H II regions in the Milky Way galaxy. It has a visual magnitude of 1.0. The astronomical coordinates are:
The nebula is one of the largest diffuse nebula in our skies. Although it is some four times as large and even brighter than the famous Orion Nebula, the Eta Carinae Nebula is much less well known, due to its location far in the southern hemisphere. It was discovered by Abbé Lacaille in 1751–52 from the Cape of Good Hope.
Within the large bright nebula is a much smaller feature, immediately surrounding Eta Carinae itself. This small nebula is known as the Homunculus Nebula (from the Latin meaning Little Man), and is believed to have been ejected in an enormous outburst in 1841 which briefly made Eta Carinae the second-brightest star in the sky.
[edit] Keyhole Nebula
A portion of the Eta Carina Nebula is known as the Keyhole Nebula, a name given to it by John Herschel in the 19th century. The Keyhole Nebula is actually a much smaller and darker cloud of cold molecules and dust, containing bright filaments of hot, fluorescing gas, silhouetted against the much brighter background nebula. The diameter of the Keyhole structure is approximately 7 light-years.
It's image has been used on the internet as a joke, due to the fact that it resembles a giant hand flipping the bird.
