| NGC 3447 | |
|---|---|
 NGC 3447 (center-right), as seen by theHubble Space Telescope. UGC 6007 can be seen on the left. | |
| Observation data (J2000epoch) | |
| Constellation | Leo |
| Right ascension | 10h 53m 24s |
| Declination | +16° 46′ 20″ |
| Redshift | 0.003559 |
| Distance | 70Mly (21.4Mpc) |
| Apparent magnitude (B) | 14.3 |
| Surface brightness | 25.37 mag/arcsec^2 (3447) and 24.38 mag/arcsec^2 (3447A) |
| Characteristics | |
| Type | SAm (3447) and Im (3447A) |
| Other designations | |
| PGC 32694/32700,UGC 6006/6007, VV 252,IRAS 10507+1702,CGCG 095-058, KPG 255 | |
NGC 3447 is abarredMagellanicspiral galaxy located in theconstellation Leo. Its speed relative to thecosmic microwave background is 1,405 ± 34 km/s, which corresponds to aHubble distance of 20.7 ± 1.5 Mpc (~67.5 million ly).[1] It was discovered by the BritishastronomerJohn Herschel in 1836.
NGC 3447 shows a broad HI line.[1]
With a surface brightness equal to 15.61 mag/am^2, NGC 3443 is classified as alow surface brightness galaxy (LSB). LSB galaxies are diffuse galaxies with a surface brightness less than one magnitude lower than that of theambient night sky.[2]
To date, four non-redshift measurements yield a distance of 13.730 ± 9.802 Mpc (~44.8 million ly),[3] which is slightly outside the range values of Hubble.
NGC 3447A, also known asUGC 6007, is anirregular galaxy in contact with NGC 3447.[1][4] It has roughly the sameapparent magnitude, and has a slightly lowersurface brightness.[1] Due togravitational forces, it has become distorted, showing disruptedspiral arms and remnants of its spiral structure, hinting it might have been a spiral galaxy in the past.[5]
ThesupernovaSN 2012ht (type Ia, mag. 18.6)[6] was discovered in NGC 3447 byKoichi Nishiyama andFujio Kabashima on December 18, 2012.[7][8]
NGC 3447 is the largest galaxy in agroup of galaxies named after it. The NGC 3447 group includes at least 4 other galaxies: NGC 3447A,NGC 3457,UGC 6022 andUGC 6035.[9]