NGC 3447

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
NGC 3447 (center-right), as seen by the Hubble Space Telescope. UGC 6007 can be seen on the left.
Observation data (J2000 epoch)
Constellation	Leo
Right ascension	10h 53m 24s
Declination	+16° 46’ 20”
Redshift	0.003559
Distance	70 Mly (21.4 Mpc)
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 shows a broad HI line.^[1]

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

NGC 3447A, also known as UGC 6007, is an irregular galaxy in contact with NGC 3447.^[1][4] It has roughly the same apparent magnitude, and has a slightly lower surface brightness.^[1] 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]

Supernova

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 group

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]

See also

• List of NGC objects (3001–4000)
• List of spiral galaxies

External links

• NGC 3447 at NASA/IPAC
• NGC 3447 at SIMBAD
• NGC 3447 at LEDA
• NGC 3447 at SEDS
• NGC 3447 (DSS2) at WikiSky
• NGC 3447 (SDSS) at WikiSky
• NGC 3447 (GALEX) at WikiSky
• NGC 3447 at Seligman

References

1. "By Name | NASA/IPAC Extragalactic Database". ned.ipac.caltech.edu. Retrieved 2024-07-21.
2. "Revised data from NGC/IC Catalogue by Wolfgang Steinckle from NGC 3400 to 3499". astrovalleyfield.ca. Retrieved 2024-07-21.
3. "NED Query Results for NGC 3447". ned.ipac.caltech.edu. Retrieved 2024-07-21.
4. Mazzei, P.; Marino, A.; Rampazzo, R.; Plana, H.; Rosado, M.; Arias, L. (2018-02-01). "Galaxy evolution in groups. NGC 3447/NGC 3447A: the odd couple in LGG 225". Astronomy and Astrophysics. 610: A8. arXiv:1710.07474. doi:10.1051/0004-6361/201731182. ISSN 0004-6361.
5. [e-mail]. "Defying cosmic convention". www.esahubble.org. Retrieved 2024-07-21.
6. Transient Name Server entry for SN 2012ht. Retrieved 23 July 2024.
7. [e-mail]. "Bright Supernovae - 2012". rochesterastronomy.org. Retrieved 2024-07-21.
8. Nishiyama, K.; Kabashima, F.; Yusa, T.; Itagaki, K.; Nakano, S.; Brimacombe, J.; Milisavljevic, D.; Martin, E. O.; Yamanaka, M.; Takaki, K.; Itoh, R.; Ueno, I.; Moritani, Y.; Akitaya, H.; Kawabata, K. S. (2012-12-01). "Supernova 2012ht in NGC 3447 = Psn J10532275+1646349". Central Bureau Electronic Telegrams. 3349: 1.
9. Garcia, A. M. (1993-07-01). "General study of group membership. II. Determination of nearby groups". Astronomy and Astrophysics Supplement Series. 100: 47–90. ISSN 0365-0138.