Pinwheel Galaxy
| Pinwheel Galaxy | |
|---|---|
The Pinwheel Galaxy, as taken by Hubble Space Telescope | |
| Observation data (J2000 epoch) | |
| Constellation | Ursa Major |
| Right ascension | 14h 03m 12.5441s |
| Declination | +54° 20′ 56.220″ |
| Redshift | 0.000804 |
| Heliocentric radial velocity | 241 ± 2 km/s |
| Distance | 21.6 ± 0.28 Mly (6.644 ± 0.087 Mpc) |
| Apparent magnitude (V) | 7.9 |
| Characteristics | |
| Type | SAB(rs)cd HII |
| Number of stars | 1 trillion (1012) |
| Size | 252,000 ly (77.31 kpc) (diameter; 4050 Å high surface brightness level) |
| Apparent size (V) | 28.8′ × 26.9′ |
| Other designations | |
| Messier 101, M101, IRAS 14013+5435, NGC 5457, Arp 26, UGC 8981, MCG +09-23-028, PGC 50063, CGCG 272-021, VV 456 | |
References: | |
The Pinwheel Galaxy (also known as Messier 101, M101 or NGC 5457) is a face-on, counterclockwise intermediate spiral galaxy located 21 million light-years (6.4 megaparsecs) from Earth in the constellation Ursa Major. It was discovered by Pierre Méchain in 1781 and was communicated that year to Charles Messier, who verified its position for inclusion in the Messier Catalogue as one of its final entries.
On February 28, 2006, NASA and the European Space Agency released a very detailed image of the Pinwheel Galaxy, which was the largest and most detailed image of a galaxy by Hubble Space Telescope at the time. The image was composed of 51 individual exposures, plus some extra ground-based photos.