| NGC 2775 | |
|---|---|
.jpg) NGC 2775 as taken by Hubble Space Telescope | |
| Observation data (J2000 epoch) | |
| Constellation | Cancer |
| Right ascension | 09h 10m 20.112s[1] |
| Declination | +07° 02′ 16.53″[1] |
| Redshift | 1,316.4±13.4 km/s[2] |
| Distance | 67 Mly (20.5 Mpc)[3] |
| Apparent magnitude (V) | 10.4[4] |
| Characteristics | |
| Type | SAa[5] or SA(r)ab[6] |
| Apparent size (V) | 4.3′ × 3.3′[6] |
| Other designations | |
| UGC 4820,[7] PGC 25861,[8] Caldwell 48 | |
NGC 2775, also known as Caldwell 48, is a spiral galaxy in the constellation Cancer. It is 67 million light-years (20.5 megaparsecs)[3] away from the Milky Way. It was discovered by William Herschel in 1783. NGC 2775 belongs to the Antlia-Hydra Cluster[9] of galaxies and is the most prominent member of the NGC 2775 Group, a small galaxy group in the Virgo Super-cluster, along with the Local Group. Other members of the NGC 2775 Group include NGC 2777 and UGC 4781.[10]
This object has a morphological classification of SA(r)ab,[6] which indicates an unbarred spiral galaxy (SA) with a prominent ring structure (r) and flocculent,[11] tightly wound spiral arms (ab).[12] The galaxy is inclined by an angle of 44° to the line of sight from the Earth.[6] The galactic nucleus is not active[2] and the large nuclear bulge, which extends out to an angular radius of 0.4′,[12] is relatively gas free.[11] An explanation for the latter could be a high supernova rate.[6] Although star formation is taking place in the dusty outer ring,[12] NGC 2775 does not display any current starburst activity,[13] and the galactic nucleus is virtually free of any star formation whatsoever.[11]
The galaxy's hydrogen tail feature indicates a past interaction with a faint companion.[6] A satellite galaxy appears to have orbited NGC 2775 multiple times, losing mass as it does so and creating faint, shell-like structures.[12] Nearby irregular galaxy NGC 2777 displays a tidal tail of hydrogen gas that points back to NGC 2775, suggesting the two may be linked.[14]
SN1993z is the only supernova known to have occurred in NGC 2775. It was detected on September 23, 1993, at a magnitude of 13.9, and was classified as a Type Ia supernova.[15] By September 25, spectral analysis showed that it had peaked four weeks earlier.[16]
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| PGC |
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| UGC |
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| Caldwell | |
New General Catalogue 2500 to 2999 | |
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