GLASS-z12 (formerly known as GLASS-z13) is a
Lyman-break galaxy discovered by the Grism Lens-Amplified Survey from Space (GLASS) observing program using the
James Webb Space Telescope's
NIRCam in July 2022.[8][9]Spectroscopic observations of GLASS-z12 by the
Atacama Large Millimeter Array (ALMA) in August 2022 confirmed that the galaxy has a
spectroscopic redshift of 12.117±0.012, making it one of the earliest and most distant galaxies ever discovered, dating back to just 350 million years after the
Big Bang,
13.6 billion years ago.[10][5] ALMA observations detected an emission line associated with
doubly ionized oxygen (O III) at 258.7 GHz with a significance of 5σ, suggesting that there is very low dust content in GLASS-z12, if not the
early universe as well.[2] Also based on oxygen-related measurements, the age of the galaxy is confirmed.[11][12]
GLASS-z12 derives its name from the GLASS survey that discovered it and its estimated photometric redshift of approximately z = 12.4+0.1 −0.3.[1] GLASS-z12 was initially announced as GLASS-z13 because it was thought to have a higher redshift of z = 13.1.[7][2] This redshift value was later revised down to z = 12.4 in October 2022, resulting in the renaming of this galaxy.[1]
^
abcBakx, Tom J. L. C.; et al. (2023). "Deep ALMA redshift search of a z ~ 12 GLASS-JWST galaxy candidate". Monthly Notices of the Royal Astronomical Society. 519 (4): 5076–5085.
arXiv:2208.13642.
doi:
10.1093/mnras/stac3723.
^
abDonnan, C. T.; et al. (November 2022). "The evolution of the galaxy UV luminosity function at redshifts z ≃ 8 - 15 from deep JWST and ground-based near-infrared imaging". Monthly Notices of the Royal Astronomical Society. 518 (4): 6011–6040.
arXiv:2207.12356.
Bibcode:
2023MNRAS.518.6011D.
doi:
10.1093/mnras/stac3472.