IC 438
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| IC 438 | |
|---|---|
.jpg) IC 438 imaged by the Hubble Space Telescope in 2021 | |
| Observation data (J2000 epoch) | |
| Constellation | Lepus |
| Right ascension | 05h 53m 00.0676s[1] |
| Declination | −17° 52′ 33.684″[1] |
| Redshift | 0.004256±0.000006[1] |
| Heliocentric radial velocity | 3,123±4 km/s[1] |
| Distance | 136.45 ± 4.29 Mly (41.835 ± 1.314 Mpc)[1] |
| Group or cluster | IC 438 Group (LGG 134) |
| Apparent magnitude (V) | 12.74[1] |
| Characteristics | |
| Type | SA(rs)c[1] |
| Size | ~155,100 ly (47.55 kpc) (estimated)[1] |
| Apparent size (V) | 2.8′ × 2.1′[1] |
| Other designations | |
| ESO 555- G 009, IRAS 05508-1753, UGCA 115, MCG -03-15-025, PGC 18047[1] | |
IC 438 is a spiral galaxy in the constellation of Lepus. Its velocity with respect to the cosmic microwave background is 3,199±6 km/s, which corresponds to a Hubble distance of 153.9 ± 10.8 Mly (47.18 ± 3.30 Mpc).[1] However, 17 non-redshift measurements give a much closer distance of 136.45 ± 4.29 Mly (41.835 ± 1.314 Mpc).[2] It was discovered by American astronomer Lewis Swift on 7 January 1891.[3][4]
IC 438 is a Seyfert I Galaxy, i.e. it has a quasar-like nucleus with very high surface brightnesses whose spectra reveal strong, high-ionisation emission lines, but unlike quasars, the host galaxy is clearly detectable.[5]
According to A.M. Garcia, IC 438 is one of five members of the IC 438 galaxy group (also known as LGG 134), which includes IC 2143, UGCA 113, MCG-03-15-021, and ESO 555-5.[6]
Supernovae
Three supernovae have been observed in IC 438:
- SN 1997B (Type Ic, mag. 16.5) was discovered by Alessandro Gabrijelcic on 13 January 1997.[7][8]
- SN 2016blx (Type II, mag. 16.5) was discovered by the Backyard Observatory Supernova Search (BOSS) on 9 April 2016.[9]
- SN 2017gbb (Type Iax[02cx-like], mag. 16.39) was discovered by the Gaia Photometric Science Alerts programme on 9 August 2017.[10]
Image gallery
IC 438 imaged by Legacy Surveys
