M105
NGC 3379
Object Data
- Catalog Designation
- M105
- Type
- Galaxy
- Constellation
- Leo
- Magnitude
- 9.3
- Right Ascension
- 10h 47m 49.6s
- Declination
- +12° 34' 54.0"
- Distance
- 38,000,000 light-years
- Angular Size
- 4.5
Survey Image
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About M105
Description
M105 is an elliptical galaxy in Leo, about 32 million light-years from Earth. It is the brightest elliptical galaxy in the Leo I Group (M96 Group) and forms a visual trio with NGC 3384 and NGC 3389. M105 harbors a supermassive black hole of about 200 million solar masses at its center.
Observing Tips
Located about 48 arcminutes north of M96. In a telescope it appears as a bright, round, featureless glow with a concentrated nucleus — characteristic of elliptical galaxies. NGC 3384 lies just 7 arcminutes to the northeast, and the two form a close pair. NGC 3389 is visible about 10 arcminutes further south. The trio makes an attractive group in moderate-aperture telescopes. Best observed from February through May.
History
Discovered by Pierre Mechain on March 24, 1781. It was not in Messier's published catalog but was added in 1947 by Helen Sawyer Hogg based on Mechain's letter describing the discovery.
Fun Facts
M105 was one of the last objects added to the Messier catalog, not included until 1947. Hubble Space Telescope observations revealed that stars in the central few light-years orbit the 200-million-solar-mass black hole at speeds up to 430 km/s. Despite appearing smooth and featureless, M105 has been found to contain a small disk of young blue stars in its center — unusual for an elliptical galaxy.
Community Photos (1)
Credit: Credit: ESA/Hubble & NASA, C. Sarazin et al.. License: CC BY 4.0. (Wikimedia Commons)
Skybred Feb 28, 2026