UGC 5139
| Constellation | Big Bear |
| Position ( equinox : J2000.0 ) | |
| Right ascension | 9h 40m 32.3s |
| declination | + 71 ° 10 '56 " |
| Appearance | |
| Hubble type | IAB (s) m |
| Apparent brightness (visual) | +13 m |
| Apparent brightness (B-band) | |
| Apparent diameter | 3.6 '× 3' |
| Surface brightness | mag / arcmin 2 |
| Physical data | |
| Affiliation | M81 group |
| distance | 12.52 million light years |
| Redshift | +0.000465 ± 0.000000 |
| Heliocentric radial relative speed | 139 ± 0 km / s |
| Absolute brightness | |
| Absolute diameter | 15,000 light years |
| Dimensions | 5.5 × 10 8 solar masses |
| Catalog names | |
| UGC 5139, PGC 27605, MCG + 12-09-059, DDO 63, Holmberg I, Mailyan 44 | |
UGC 5139 , also named Holmberg I after its discoverer , is a dwarf galaxy in the constellation Great Bear , about 12.5 million light years away from Earth .
discovery
The galaxy UGC 5139 was discovered by the Swedish astronomer Erik Bertil Holmberg in the 1950s .