Messier 104, Sombrero Galaxy

Messier 104
Messier 104: Image taken with the Hubble Space Telescope [183]

History

The galaxy M 104 was discovered by Pierre Méchain on May 11, 1781. It was not originally included in Messier's catalog. In his personal copy of the «Connoissance des Temps» published in 1784, Messier added the discovery of Méchain and described it as «a very faint nebula». It was not until 1921 that Camille Flammarion discovered Messier's notes, identified them as NGC 4594 and added it to the Messier catalog as M 104.

Physical Properties

M 104 was nicknamed the «Sombrero Galaxy» because of the distinctive dust ring in which new stars emerge. We see the galaxy at an angle of about 6 degrees. The galaxy is of the SA(s)a type and has an active core of the LINER type, in which a supermassive black hole of one billion solar masses is suspected. The high number of globular clusters is also remarkable. Around 2000 of these are estimated to belong to the galaxy. Their age is estimated to be 10 to 13 billion years. Heliocentric speeds measured in the last 20 years are in the range from 1087 km/s to 1095 km/s and distances determined with different methods range from 8.9 Mpc to 21 Mpc. [145, 215]

«Catalogue of Principal Galaxies (PGC)», Paturel et al. 1989 [144]
DesignationsPGC 42407: NGC 4594, MCG 2-32-20, UGCA 293, M 104, IRAS 12373-1120
Right Ascension (J2000.0)12h 39m 59.3s
Declination (J2000.0)-11° 37' 23"
Morphological TypeS
Dimensions8.6' x 4.2'
Visual Magnitude9.2 mag
Radial Velocity (HRV)1089 km/s
Position Angle89°

Finder Chart

Below the constellation Virgo on the border with the constellation Corvus is the Sombrero galaxy. The galaxy with the number 104 in the Messier catalog is located in an area sparsely populated with bright stars. With its brightness of 9.2 mag, it is still easy to find. [192]

Chart M 104
Chart created using SkySafari 6 Pro and STScI Digitized Sky Survey. [149, 160]

Visual Observation

The sombrero galaxy is clearly visible even in binoculars. The elongated galaxy has a strong spindle shape, which can be seen in small to medium-sized telescopes. The black, slightly decentralized congestion belt can be easily made out with medium-sized telescopes. M104 is one of the most worthwhile objects among the spindle-shaped dust-banded galaxies. [192]

14" PWO-Dobson, F:4.6 / TV-Nagler 13mm, 123x, 0.67° und TV-Radian 8mm, 200x, 0.3°
Eduard von Bergen

M 104
M 104: EAA, roughly represents visual impression; 30" SlipStream Dobson f/3.3 + MallinCam video camera; ca. 3s; Hasliberg; © 14. 3. 2012 Eduard von Bergen

762 mm aperture: The visual impression can be reproduced with a MallinCam video camera and an integration time of around three seconds. A tracking 30" f/3.3 SlipStream Dobsonian was used. The resulting image comes very close to visual vision with a 13 mm Tele Vue Ethos eyepiece.

— 14. 3. 2012, Eduard von Bergen

References

144Catalogue of Principal Galaxies (PGC); Paturel G., Fouque P., Bottinelli L., Gouguenheim L.; Astron. Astrophys. Suppl. Ser. 80, 299 (1989); cdsarc.unistra.fr/viz-bin/cat/VII/119 (2021-02-18)
145SIMBAD astronomical database; simbad.u-strasbg.fr/simbad
149SkySafari 6 Pro, Simulation Curriculum; skysafariastronomy.com
160The STScI Digitized Sky Survey; archive.stsci.edu/cgi-bin/dss_form
183The Majestic Sombrero Galaxy (M104); hubblesite.org/contents/media/images/2003/28/1415-Image.html (2020-12-23)
192Deep-Sky Guide; fernrohr.ch/1d_deep-sky-guide.html (2020-12-25)
215Explore - The Night Sky | Hubble’s Messier Catalog; nasa.gov/content/goddard/hubble-s-messier-catalog (2020-12-31)