HCM-6A
Encyclopedia
HCM-6A is a 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
in the constellation Cetus
, which enabled the astronomers to use Abell 370 as a gravitational lens
to get a clearer image of the object.
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.
Galaxy
A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust, and an important but poorly understood component tentatively dubbed dark matter. The word galaxy is derived from the Greek galaxias , literally "milky", a...
that was found in 2002 by a team led by Esther Hu from the University of Hawaii
University of Hawaii
The University of Hawaii System, formally the University of Hawaii and popularly known as UH, is a public, co-educational college and university system that confers associate, bachelor, master, and doctoral degrees through three university campuses, seven community college campuses, an employment...
, using the Keck II Telescope in Hawaii
Hawaii
Hawaii is the newest of the 50 U.S. states , and is the only U.S. state made up entirely of islands. It is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean, southwest of the continental United States, southeast of Japan, and northeast of...
. HCM-6A is located behind the Abell 370
Abell 370
Abell 370 is a galaxy cluster located approximately 6 billion light years away from the Earth , in the constellation Cetus. Its core is made up of several hundred galaxies...
galactic cluster, near M77
Messier 77
Messier 77 is a barred spiral galaxy about 47 million light-years away in the constellation Cetus. Messier 77 is an active galaxy with an Active Galactic Nucleus , which is obscured from view by astronomical dust at visible wavelengths...
in the constellation Cetus
Cetus
Cetus is a constellation. Its name refers to Cetus, a sea monster in Greek mythology, although it is often called 'the whale' today. Cetus is located in the region of the sky that contains other water-related constellations such as Aquarius, Pisces, and Eridanus.-Ecliptic:Although Cetus is not...
, which enabled the astronomers to use Abell 370 as a gravitational lens
Gravitational lens
A gravitational lens refers to a distribution of matter between a distant source and an observer, that is capable of bending the light from the source, as it travels towards the observer...
to get a clearer image of the object.
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.