Trifid Nebula
From Biocrawler, the free encyclopedia.
The Trifid Nebula (also known as M20 and NGC 6514) is an H II region at right ascension 18h 02.3m and declination -23° 02', located in Sagittarius. The nebula's name means "divided into three lobes".
The lower photo was taken by the Hubble Space Telescope and shows a detail of the nebula. This close-up shows a dense cloud of dust and gas, a stellar nursery full of embryonic stars. This cloud is about 8 light-years away from the nebula's central star, not shown in this picture.
A stellar jet (the thin, wispy object pointing to the upper left) protrudes from the head of the cloud and is about .75 light-years long. The jet's source is a young stellar object deep within the cloud. Jets are the exhaust gasses of star formation. Radiation from the nebula's central star makes the jet glow.
The finger-like object to the right of the jet is a stalk. It is pointing from the head of the dense cloud directly toward the star that powers the Trifid nebula. This stalk is a prominent example of the evaporating gaseous globules, or "EGG's". The stalk has survived because its tip is a knot of gas that is dense enough to resist being eaten away by the powerful radiation from the star.
The images were taken September 8, 1997 through filters that isolate emission from hydrogen atoms, ionized sulfur atoms, and doubly ionized oxygen atoms. The images were combined into a false-color composite picture to suggest how the nebula might look to the eye.
In January, 2005 NASA's Spitzer Space Telescope discovered 30 embryonic stars and 120 newborn stars not viewable in visible light images.
Related topics
External links
- Spitzer IR Trifid discoveries (http://www.spitzer.caltech.edu/Media/releases/ssc2005-02/ssc2005-02a.shtml)
- Messier 20 (http://www.seds.org/messier/m/m020.html), SEDS Messier pagesit:M20
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