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IC5146 - Cocoon
M5 - NGC5904
M8 - Lagoon Nebula
M16 - Eagle Nebula
M20 - Trifid
M27 - Dumbbell
M31 - Andromeda
M33 - Pinwheel
M42 - Orion
M45 - The Pleiades
M51 - Whirlpool
M57 - Ring
M63 - Sunflower
M64 - Black-Eye
M65 - NGC3623
M67 - NGC2682
M98 - NGC4192
M99 - Pinwheel
M100 - NGC4321
M101 - NGC5457
M104 - Sombrero
M105 - NGC3379
M106 - NGC4258
C/2004 Q2 - Machholz
NGC 891
NGC2024 - Flame
NGC2244 - Rosette
NGC6960 - Veil
The Mice - NGC4676










(Credits to SEDS _ Students for the Exploration and Development of Space)

Spiral Galaxy M104 (NGC 4594), type Sa, in Virgo

Sombrero Galaxy

Discovered by Pierre Méchain in 1781.

Messier 104 (M104, NGC 4594) is numerically the first object of the catalog which was not included in Messier's originally published catalog. However, Charles Messier added it by hand to his personal copy on May 11, 1781, and described it as a "very faint nebula." It was Camille Flammarion who found that its position coincided with Herschel's H I.43, which is the Sombrero Galaxy (NGC 4594), and added it to the official Messier list in 1921. This object is also mentioned by Pierre Méchain as his discovery in his letter of May 6, 1783. William Herschel found this object independently on May 9, 1784.

This brilliant galaxy was named the Sombrero Galaxy because of its appearance. According to de Vaucouleurs, we view it from just 6 degrees south of its equatorial plane, which is outlined by a rather thick dark rim of obscuring dust. This dust lane was probably the first discovered, by William Herschel in his great reflector.

This galaxy is of type Sa-Sb, with both a big bright core, and as one can see in shorter exposures, also well-defined spiral arms. It also has an unusually pronounced bulge with an extended and richly populated globular cluster system - several hundred can be counted in long exposures from big telescopes.

Recent very deep photographs from the Australian Astronomical Observatory show that this galaxy has a very extended faint halo.

This galaxy was the first one with a large redshift found, by Vesto M. Slipher at Lowell Observatory in 1912. Its redshift corresponds to a recession velocity of about 1,000 km/sec (it is caused by the Hubble effect, i.e. the cosmic expansion). This was too fast for the Sombrero to be an object in our Milky Way galaxy. Slipher also detected the galaxy's (then the nebula's) rotation.

M104 is the dominating member of a small group of galaxies, the M104 group or NGC 4594 group of galaxies.

(Credits to SEDS - Students for the Exploration and Development of Space)


Observer´s Log

Spiral Galaxy
Sombrero Galaxy
Dreyer description: Remarkable!, very bright, very large, extremely extended 92°, very abruptly much brighter middle nucleus; = M104.
Other ID: MCG-2-32-20
Other ID: UGCA293
Other ID: MESS104
Other ID: PGC42407
Magnitude: 8.6
RA: 12h 40m 09.7s Dec: -11°38'30"
RA: 12h 39m 59.3s Dec: -11°37'22" (Epoch 2000)
Size: 8.7' x 3.5'
Position Angle: 88.0







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This site was last updated 2019-02-10                                                                                                          Site created and maintained by Jorge Lázaro