| NGC 3447 | |
| Ra: | 10h 53m 24s |
| Dec: | +16° 46’ 20” |
| Type: | SAm (3447) and Im (3447A) |
| Appmag B: | 14.3 |
| Epoch: | J2000 |
| Sbrightness: | 25.37 mag/arcsec^2 (3447) and 24.38 mag/arcsec^2 (3447A) |
| Constellation Name: | Leo |
| Names: | PGC 32694/32700, UGC 6006/6007, VV 252, IRAS 10507+1702, CGCG 095-058, KPG 255 |
| Z: | 0.003559 |
| Dist Ly: | 70 Mly (21.4 Mpc) |
NGC 3447 is a barred Magellanic spiral galaxy located in the constellation Leo. Its speed relative to the cosmic microwave background is 1,405 ± 34 km/s, which corresponds to a Hubble distance of 20.7 ± 1.5 Mpc (∼67.5 million ly).[1] It was discovered by the British astronomer John Herschel in 1836.
NGC 3447 shows a broad HI line.
With a surface brightness equal to 15.61 mag/am^2, NGC 3443 is classified as a low surface brightness galaxy (LSB). LSB galaxies are diffuse galaxies with a surface brightness less than one magnitude lower than that of the ambient 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 as UGC 6007, is an irregular galaxy in contact with NGC 3447.[4] It has roughly the same apparent magnitude, and has a slightly lower surface brightness. Due to gravitational forces, it has become distorted, showing disrupted spiral arms and remnants of its spiral structure, hinting it might have been a spiral galaxy in the past.[5]
The supernova SN 2012ht (type Ia, mag. 18.6)[6] was discovered in NGC 3447 by Koichi Nishiyama and Fujio Kabashima on December 18, 2012.[7] [8]
NGC 3447 is the largest galaxy in a group of galaxies named after it. The NGC 3447 group includes at least 4 other galaxies: NGC 3447A, NGC 3457, UGC 6022 and UGC 6035.[9]