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Observation data (J2000 epoch)
Constellation Camelopardalis
Right ascension 06h 47m 55.73s
Declination +70° 14′ 35.7″
Redshift 10.7
Distance 13.3 billion light years
Size (ly) 600 ly (diameter)
See also: Galaxy, List of galaxies

MACS0647-JD is a candidate, based on a photometric redshift estimate,[1][2] for the farthest known galaxy from Earth at a redshift of about z = 10.7,[3] equivalent to a light travel distance of 13.3 billion light-years (4 billion parsecs). If the distance estimate is correct, it formed 420 million years after the Big Bang.[4] It is less than 600 light-years wide.

The galaxy was discovered with the help of Cluster Lensing And Supernova survey with Hubble (CLASH), which uses massive galaxy clusters as cosmic telescopes to magnify distant galaxies behind them, an effect called gravitational lensing. Observations were recorded by the Wide Field Camera 3 on the Hubble Space Telescope,[4] with support from Spitzer Space Telescope.[3]

The location of the galaxy is in the constellation Camelopardalis, which is also the location of the gravitational lensing cluster that helped discover this galaxy: MACSJ0647+7015 at z = 0.591.[5]

MACS0647-JD was announced in November 2012, but by the next month UDFj-39546284, which was previously thought to be z = 10.3, was said to be at z = 11.9,[6] although more recent analyses have suggested the latter is likely to be at a lower redshift.[7] Spectroscopic confirmation of the redshift of MACS0647-JD likely awaits the launch of the James Webb Space Telescope expected in 2018.[8]


MACS0647-JD is very young and only a tiny fraction of the size of the Milky Way.[9]

A confirming paper was published in the December 20, 2012 issue of The Astrophysical Journal. A preprint of the paper is available on arXiv.[3]

Photometric redshift z = 10.7 +0.6 / −0.4 (95% confidence limits; with z < 9.5 galaxies of known types ruled out at 7.2-sigma).[3]

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