HCM-6A is an LAE galaxy that was found in 2002 by a team led by Esther Hu from the University of Hawaii, using the Keck II Telescope in Hawaii. HCM-6A is located behind the Abell 370 galactic cluster, near M77 [1] in the constellation Cetus, which enabled the astronomers to use Abell 370 as a gravitational lens to get a clearer image of the object.[2][3]

Observation data (J2000 epoch)
Right ascension 02h 39m 54.7s
Declination−01° 33′ 32″
Distance12.8 billion light years
Apparent magnitude (V)24.24
Other designations
HCB2010 J023954-013332
See also: Galaxy, List of galaxies

HCM-6A was the farthest object known at the time of its discovery. It exceeded SSA22−HCM1 (z = 5.74) as the most distant normal galaxy known, and quasar SDSSp J103027.10+052455.0 (z = 6.28) as the most distant object known. In 2003, SDF J132418.3+271455 (z = 6.578) was discovered, and took over the title of most remote object known, most remote galaxy known, and most remote normal galaxy known.


  1. ^ Halton Arp & David Russell (2001). "A Possible Relationship between Quasars and Clusters of Galaxies". The Astrophysical Journal. 549 (2): 802–819. Bibcode:2001ApJ...549..802A. doi:10.1086/319438.
  2. ^ E. M. Hu, et al. (2001). "A Redshift z = 6.56 Galaxy behind the Cluster Abell 370". The Astrophysical Journal Letters. 568 (2): L75–L79. arXiv:astro-ph/0203091. Bibcode:2002ApJ...568L..75H. doi:10.1086/340424.
  3. ^ Press release, National Astronomical Observatory of Japan, September 13, 2006
Preceded by
SDSSp J103027.10+052455.0
Most distant astronomical object
2002 — 2003
Succeeded by
SDF J132418.3+271455
Preceded by
Most distant galaxy
2002 — 2003
Succeeded by
SDF J132418.3+271455