• Source: Trifid Nebula

The Trifid Nebula (catalogued as Messier 20 or M20 and as NGC 6514) is an H II region in the north-west of Sagittarius in a star-forming region in the Milky Way's Scutum–Centaurus Arm. It was discovered by Charles Messier on June 5, 1764. Its name means 'three-lobe'. The object is an unusual combination of an open cluster of stars, an emission nebula (the relatively dense, reddish-pink portion), a reflection nebula (the mainly NNE blue portion), and a dark nebula (the apparent 'gaps' in the former that cause the trifurcated appearance, also designated Barnard 85). Viewed through a small telescope, the Trifid Nebula is a bright and peculiar object, and is thus a perennial favorite of amateur astronomers.
The most massive star that has formed in this region is HD 164492A, an O7.5III star with a mass more than 20 times the mass of the Sun.
This star is surrounded by a cluster of approximately 3100 young stars.




Characteristics


The Trifid Nebula was the subject of an investigation by astronomers using the Hubble Space Telescope in 1997, using 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.
The close-up images show a dense cloud of dust and gas, which is a stellar nursery full of embryonic stars. This cloud is about
8 ly away from the nebula's central star. A stellar jet protrudes from the head of the cloud and is about 0.75 ly long. The jet's source is a young stellar object deep within the cloud. Jets are the exhaust gasses of star formation and radiation from the nebula's central star makes the jet glow.
The images also showed a finger-like stalk to the right of the jet. It points from the head of the dense cloud directly toward the star that powers the Trifid nebula. This stalk is a prominent example of evaporating gaseous globules, or 'EGGs'. 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.
In January 2005, NASA's Spitzer Space Telescope discovered 30 embryonic stars and 120 newborn stars not seen in visible light images.
It is centered about 4100 ly from Earth. Its apparent magnitude is 6.3.




Details and features



































See also


List of Messier objects
List of nebulae
Messier object
New General Catalogue
Wikipedia Project: Astronomical Objects
Islands (King Crimson album), which uses an image of the nebula as its cover




References






External links



New Views of a Familiar Beauty, Spitzer IR Trifid discoveries
Messier 20, SEDS Messier pages
Search results for 'Trifid Nebula' at ESA/Hubble
Merrifield, Michael. "M20 – Trifid Nebula". Deep Sky Videos. Brady Haran.

The Trifid Nebula on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images
Trifid Nebula – Messier 20 at Constellation Guide

Kata Kunci Pencarian:

• Nebula Trifid
• Daftar nebula gelap
• Objek Messier
• Daftar objek NGC 6001 - 7000
• Astronomy Picture of the Day
• Bintang Pistol
• Astrofotografi
• Lengan Carina–Sagittarius
• Observatorium Bosscha
• Wilayah H II
• Trifid Nebula
• Trifid
• Nebula
• Sagittarius (constellation)
• Reflection nebula
• NGC 1579
• Emission nebula
• Nebular hypothesis
• Astronomy Picture of the Day
• Islands (King Crimson album)