|RD1 (0140+326 RD1)|
RD1 as viewed by the W. M. Keck Observatory
|Observation data (J2000 epoch)|
|Right ascension||01h 43m 42.8s|
|Declination||+32° 54′ 00.0″|
|Distance||around 12.5 billion light-years
(light travel distance)
~26 billion light-years
(present comoving distance)
RD1 or 0140+326 RD1 is a distant galaxy, it once held the title of most distant galaxy known. RD1 was discovered in March 1998, and is at z = 5.34, and was the first object found to exceed redshift 5. It bested the previous recordholders, a pair of galaxies at z=4.92 lensed by the galaxy cluster CL 1358+62 (CL 1358+62 G1 & CL 1358+62 G2). It was the most distant object known to mankind for a few months in 1998, until BR1202-0725 LAE was discovered at z = 5.64.
The "distance" of a far away galaxy depends on what distance measurement you use. With a redshift of 5.34, light from this galaxy is estimated to have taken around 12.5 billion years to reach us. But since this galaxy is receding from Earth, the present comoving distance is estimated to be around 26 billion light-years.
- arXiv, PDF (209 KB), 11 March 1998
- Edward L. (Ned) Wright. "Cosmology Calculator I". Astronomy @ UCLA. Retrieved 2010-10-22.
- Astronomy Picture of the Day, A Baby Galaxy, March 24, 1998
- New York Times, Peering Back in Time, Astronomers Glimpse Galaxies Aborning, October 20, 1998
ClG 1358+62 G1+G2
|Most distant galaxy
BR 1202-0725 LAE