List of the most distant astronomical objects

This article documents the most distant astronomical objects discovered and verified so far, and the time periods in which they were so classified.

For comparisons with the light travel distance of the astronomical objects listed below, the age of the universe since the Big Bang is currently estimated as 13.787±0.020 Gyr.

[1] Distances to remote objects, other than those in nearby galaxies, are nearly always inferred by measuring the cosmological redshift of their light.

By their nature, very distant objects tend to be very faint, and these distance determinations are difficult and subject to errors.

An important distinction is whether the distance is determined via spectroscopy or using a photometric redshift technique.

Since the beginning of the James Webb Space Telescope's (JWST) science operations in June 2022, numerous distant galaxies far beyond what could be seen by the Hubble Space Telescope (z = 11) have been discovered thanks to the JWST's capability of seeing far into the infrared.

[45][46] Previously in 2012, there were about 50 possible objects z = 8 or farther, and another 100 candidates at z = 7, based on photometric redshift estimates released by the Hubble eXtreme Deep Field (XDF) project from observations made between mid-2002 and December 2012.

[47] Some objects included here have been observed spectroscopically, but had only one emission line tentatively detected, and are therefore still considered candidates by researchers.

Objects may have been discovered without distance determination, and were found subsequently to be the most distant known at that time.

An object like OJ 287 is ignored even though it was detected as early as 1891 using photographic plates, but ignored until the advent of radiotelescopes.