|Observation data (J2000 epoch)|
|Right ascension||13h 23m 59.8s|
|Declination||+27° 24′ 56″|
|Distance||12.88 billion light-years (3.95 Gpc)|
|Apparent magnitude (V)||24.4|
It was discovered in April 2006 by Masanori Iye at National Astronomical Observatory of Japan using the Subaru Telescope in Hawaii and seen as it was 12.88 billion years ago. Its emission of Lyman alpha radiation has a redshift of 6.96, corresponding to just 750 million years after the Big Bang. While some scientists have claimed other objects (such as Abell 1835 IR1916) to be even older, the IOK-1's age and composition have been more reliably established.
"IOK" stands for the observers' names Iye, Ota, and Kashikawa.
- Hogan, Jenny (2006), "Journey to the birth of the Universe", Nature, 443 (7108): 128–129, Bibcode:2006Natur.443..128H, doi:10.1038/443128a, PMID 16971914
- Iye, Masanori; Ota, Kazuaki; Kashikawa, Nobunari; Furusawa, Hisanori; Hashimoto, Tetsuya; Hattori, Takashi; Matsuda, Yuichi; Morokuma, Tomoki; Ouchi, Masami; et al. (2006), "A galaxy at a redshift z = 6.96", Nature, 443 (7108): 186–188, arXiv:astro-ph/0609393v1, Bibcode:2006Natur.443..186I, doi:10.1038/nature05104, PMID 16971942
- Press release, National Astronomical Observatory of Japan, September 13, 2006
| Most distant astronomical object
| Most distant galaxy