Trifid Nebula
The Trifid nebula.The outlined area is enlarged below.
A stellar jet in the Trifid nebula. For explanation of this image, see the article.
The Trifid Nebula is an emission nebula at right ascension 18h 02.3m and declination -23° 02', located in the Sagittarius constellation.
The Trifid Nebula is also called M20.
A stellar jet (the thin, wispy object pointing to the upper left)
protrudes from the head of the cloud and is about three quarters of a light-year (4,000,000,000,000 miles) long . The jet's source is a very young stellar
object that lies buried within the cloud. Jets such as this are the
exhaust gases of star formation. Radiation from the massive star at
the center of the nebula is making the gas in the jet glow, just as it
causes the rest of the nebula to glow.
The picture also shows a "stalk" (the finger-like object, to the right of the jet) 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 "EGGs". The stalk has survived because at its tip there 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 in a single color composite
picture. While the resulting picture is not true color, it is suggestive of the how this nebula would look to the eye.Notes on the lower picture
The Hubble Space Telescope image (which is an enlargement of the outlined area of the upper picture) shows a small part of 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, which is beyond the
top of the picture.
(Text courtesy of NASA)
