NGC 2403
| NGC 2403 | |
|---|---|
A Hubble Space Telescope (HST), and Subaru image of NGC 2403. NGC 2404 is visible | |
| Observation data (J2000 epoch) | |
| Constellation | Camelopardalis |
| Right ascension | 07h 36m 51.298s |
| Declination | +65° 36′ 09.662″ |
| Redshift | 0.000445 |
| Heliocentric radial velocity | 133 ± 0 km/s |
| Distance | 9.65 Mly (2.96 Mpc) |
| Apparent magnitude (V) | 8.9 |
| Characteristics | |
| Type | SAB(s)cd |
| Size | ~90,300 ly (27.69 kpc) (estimated) |
| Apparent size (V) | 21.9′ × 12.3′ |
| Other designations | |
| Caldwell 7, IRAS 07321+6543, UGC 3918, PGC 21396, CGCG 309-040 | |
NGC 2403 (also known as Caldwell 7) is an intermediate spiral galaxy in the constellation Camelopardalis. It is an outlying member of the M81 Group, and is approximately 8 million light-years distant. It bears a similarity to M33, containing numerous star-forming H II regions, but being a little bit larger at approximately 90,000 light-years in diameter compared to the 61,100 light-year diameter of M33. The northern spiral arm connects it to the star forming region NGC 2404. NGC 2403 can be observed using 10×50 binoculars. NGC 2404 is 940 light-years in diameter, making it one of the largest known H II regions. This H II region represents striking similarity with NGC 604 in M33, both in size and location in galaxy.