This article documents the farthest known astronomical objects, and the time periods in which they were so classified.

List of most distant objects by type

Most distant object by type

Type	Object	Distance	Notes
Any astronomical object Astronomical object Astronomical objects or celestial objects are naturally occurring physical entities, associations or structures that current science has demonstrated to exist in the observable universe. The term astronomical object is sometimes used interchangeably with astronomical body... , no matter what type	UDFj-39546284 UDFj-39546284 UDFj-39546284 is a compact galaxy of blue stars that existed as we see it 13.2 billion years ago, around 480 million years after the Big Bang. It is the oldest galaxy found and exceeds the previous distance record holder by roughly 150 million years. It could remain so until the anticipated launch...	z Redshift In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum... =~10.3
Galaxy Galaxy A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust, and an important but poorly understood component tentatively dubbed dark matter. The word galaxy is derived from the Greek galaxias , literally "milky", a...  or protogalaxy Protogalaxy In physical cosmology, a protogalaxy, which could also be called a "primeval galaxy", is a cloud of gas which is forming into a galaxy. It is believed that the rate of star formation, during this period of galactic evolution, will determine whether a galaxy is a spiral or elliptical galaxy; a...	UDFj-39546284 UDFj-39546284 UDFj-39546284 is a compact galaxy of blue stars that existed as we see it 13.2 billion years ago, around 480 million years after the Big Bang. It is the oldest galaxy found and exceeds the previous distance record holder by roughly 150 million years. It could remain so until the anticipated launch...	z Redshift In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum... =~10.3
Galaxy cluster Galaxy cluster A galaxy cluster is a compact cluster of galaxies. Basic difference between a galaxy group and a galaxy cluster is that there are many more galaxies in a cluster than in a group. Also, galaxies in a cluster are more compact and have higher velocity dispersion. One of the key features of cluster is...  or protocluster
Galaxy supercluster
Galaxy hypercluster (Wall, Sheet, Filament of galaxies) Galaxy filament In physical cosmology, galaxy filaments, also called supercluster complexes or great walls, are, so far, the largest known cosmic structures in the universe. They are massive, thread-like structures with a typical length of 50 to 80 megaparsecs h-1 that form the boundaries between large voids in...
Quasar Quasar A quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...	ULAS J1120+0641 ULAS J1120+0641 ULAS J1120+0641 is a quasar, the discovery of which was reported on 29 June 2011. , it is the most distant known quasar, and it was the first quasar discovered beyond a redshift of 7. Various news reports, including those provided by the Associated Press, have stated that it is the brightest object...	z=7.085
Black hole Black hole A black hole is a region of spacetime from which nothing, not even light, can escape. The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that...	ULAS J1120+0641 ULAS J1120+0641 ULAS J1120+0641 is a quasar, the discovery of which was reported on 29 June 2011. , it is the most distant known quasar, and it was the first quasar discovered beyond a redshift of 7. Various news reports, including those provided by the Associated Press, have stated that it is the brightest object...	z=7.085
Star Star A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...  or protostar Protostar A protostar is a large mass that forms by contraction out of the gas of a giant molecular cloud in the interstellar medium. The protostellar phase is an early stage in the process of star formation. For a one solar-mass star it lasts about 100,000 years...  or post-stellar corpse	Progenitor of GRB 090429B GRB 090429B GRB 090429B was a gamma-ray burst first detected on 29 April 2009, the second detected that day. Though this burst was detected in 2009, it was not until 2011 that its distance was announced, have a redshift of z=9.4, becoming the most distant GRB known in May 2011, usurping GRB 090423.On 2009...	z=~9.4
Star cluster Star cluster Star clusters or star clouds are groups of stars. Two types of star clusters can be distinguished: globular clusters are tight groups of hundreds of thousands of very old stars which are gravitationally bound, while open clusters, more loosely clustered groups of stars, generally contain less than...
Nebula Nebula A nebula is an interstellar cloud of dust, hydrogen gas, helium gas and other ionized gases...	Remnant of GRB 090429B GRB 090429B GRB 090429B was a gamma-ray burst first detected on 29 April 2009, the second detected that day. Though this burst was detected in 2009, it was not until 2011 that its distance was announced, have a redshift of z=9.4, becoming the most distant GRB known in May 2011, usurping GRB 090423.On 2009...	z=~9.4

Most distant event by type

Type	Event	Distance	Notes
Gamma-ray burst	GRB 090429B GRB 090429B GRB 090429B was a gamma-ray burst first detected on 29 April 2009, the second detected that day. Though this burst was detected in 2009, it was not until 2011 that its distance was announced, have a redshift of z=9.4, becoming the most distant GRB known in May 2011, usurping GRB 090423.On 2009...	z=~9.4
Supernova Supernova A supernova is a stellar explosion that is more energetic than a nova. It is pronounced with the plural supernovae or supernovas. Supernovae are extremely luminous and cause a burst of radiation that often briefly outshines an entire galaxy, before fading from view over several weeks or months...	SN 19941	z=2.357
Cosmic Decoupling Recombination (cosmology) In cosmology, recombination refers to the epoch at which charged electrons and protons first became bound to form electrically neutral hydrogen atoms.Note that the term recombination is a misnomer, considering that it represents the first time that electrically neutral hydrogen formed. After the...	Cosmic Background Radiation creation	z~1000

Most distant astronomical object recordholders

Objects in this list were found to be the most distant known object at the time of determination of their distance. This is frequently not the same as the date of their discovery.

Distances to astronomical objects may be determined through parallax

Parallax

Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"...

 measurements, use of standard references

Standard Candles

Standard Candles is a compilation of short stories by American science fiction author Jack McDevitt. The sixteen stories in the anthology were originally published in various magazines from 1982 to 1996...

 such as cepheid variable

Cepheid variable

A Cepheid is a member of a class of very luminous variable stars. The strong direct relationship between a Cepheid variable's luminosity and pulsation period, secures for Cepheids their status as important standard candles for establishing the Galactic and extragalactic distance scales.Cepheid...

s or Type Ia supernova

Type Ia supernova

A Type Ia supernova is a sub-category of supernovae, which in turn are a sub-category of cataclysmic variable stars, that results from the violent explosion of a white dwarf star. A white dwarf is the remnant of a star that has completed its normal life cycle and has ceased nuclear fusion...

s, or redshift

Redshift

In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum...

 measurement. Spectroscopic redshift measurement is preferred, while photometric redshift

Photometric redshift

A photometric redshift is an estimate for the distance of an astronomical object, such as a galaxy or quasar. The technique uses photometry to determine the redshift, and hence, through Hubble's...

 measurement is also used. The unit z represents redshift.

Most Distant Object Titleholders

Object	Type	Date	Distance	Notes
UDFj-39546284 UDFj-39546284 UDFj-39546284 is a compact galaxy of blue stars that existed as we see it 13.2 billion years ago, around 480 million years after the Big Bang. It is the oldest galaxy found and exceeds the previous distance record holder by roughly 150 million years. It could remain so until the anticipated launch...	Galaxy Galaxy A galaxy is a massive, gravitationally bound system that consists of stars and stellar remnants, an interstellar medium of gas and dust, and an important but poorly understood component tentatively dubbed dark matter. The word galaxy is derived from the Greek galaxias , literally "milky", a...	2011 —	z Redshift In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum... =~10.3	Announced January 26, 2011 also based on studies of images captured earlier in the Hubble Ultra Deep Field Hubble Ultra Deep Field The Hubble Ultra-Deep Field is an image of a small region of space in the constellation Fornax, composited from Hubble Space Telescope data accumulated over a period from September 24, 2003, through to January 16, 2004...  survey. (Not spectroscopically confirmed Spectroscopy Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative... )
UDFy-38135539 UDFy-38135539 UDFy-38135539 is the Hubble Ultra Deep Field identifier for a galaxy which has been calculated to have a light travel time of 13.1 billion years with a present comoving distance of around 30 billion light-years...	Galaxy	2010 − 2011	z Redshift In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum... =8.55	Announced October 20, 2010 based on studies of images captured earlier in the Hubble Ultra Deep Field Hubble Ultra Deep Field The Hubble Ultra-Deep Field is an image of a small region of space in the constellation Fornax, composited from Hubble Space Telescope data accumulated over a period from September 24, 2003, through to January 16, 2004...  survey.
Progenitor of GRB 090423 GRB 090423 GRB 090423 is a gamma-ray burst detected by the Swift Gamma-Ray Burst Mission on April 23, 2009 at 07:55:19 UTC. The afterglow of GRB 090423 was detected in the infrared, and allowed astronomers to determine that the redshift of GRB 090423 is z = 8.2, which makes GRB 090423 the second...  / Remnant of GRB 090423 GRB 090423 GRB 090423 is a gamma-ray burst detected by the Swift Gamma-Ray Burst Mission on April 23, 2009 at 07:55:19 UTC. The afterglow of GRB 090423 was detected in the infrared, and allowed astronomers to determine that the redshift of GRB 090423 is z = 8.2, which makes GRB 090423 the second...	Gamma-ray burst progenitor / Gamma-ray burst remnant	2009 − 2010	z=8.2
IOK-1 IOK-1 IOK-1 is a distant galaxy in Coma Berenices. When discovered in 2006, it was the oldest and most distant galaxy ever found, at redshift 6.96....	Galaxy	2006 − 2009	z=6.96
SDF J132522.3+273520	Galaxy	2005 − 2006	z=6.597
SDF J132418.3+271455	Galaxy	2003 − 2005	z=6.578
HCM-6A HCM-6A HCM-6A is a galaxy that was found in 2002 by a team led by Esther Hu from the University of Hawaii, using the Keck II Telescope in Hawaii. HCM-6A is located behind the Abell 370 galactic cluster, near M77 in the constellation Cetus, which enabled the astronomers to use Abell 370 as a gravitational...	Galaxy	2002 − 2003	z=6.56	The galaxy is lensed by galaxy cluster Abell 370 Abell 370 Abell 370 is a galaxy cluster located approximately 6 billion light years away from the Earth , in the constellation Cetus. Its core is made up of several hundred galaxies... . This was the first non-quasar galaxy found to exceed redshift 6. It exceeded the redshift of quasar SDSSp J103027.10+052455.0 of z=6.28
SDSS J1030+0524  (SDSSp J103027.10+052455.0)	Quasar Quasar A quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...	2001 − 2002	z=6.28
SDSS 1044-0125  (SDSSp J104433.04-012502.2)	Quasar	2000 − 2001	z=5.82
SSA22-HCM1	Galaxy	1999 − 2000	z=5.74
HDF 4-473.0	Galaxy	1998 − 1999	z=5.60
RD1 RD1 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...  (0140+326 RD1)	Galaxy	1998	z=5.34
CL 1358+62 G1 & CL 1358+62 G2	Galaxies	1997 − 1998	z=4.92	These were the remotest objects known at the time of discovery. The pair of galaxies were found lensed by galaxy cluster CL1358+62 CL1358+62 CL 1358+62 is a galaxy cluster located at z=0.33 redshift. Behind the cluster, lensed into a red arc is an infant galaxy that was the farthest object in the observable universe for a few months. It had a record redshift of z=4.92 and was discovered on July 31, 1997 by M. Franx and G. Illingsworth....  (z=0.33). This was the first time since 1964 that something other than a quasar Quasar A quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...  held the record for being the most distant object in the universe.
PC 1247-3406	Quasar	1991 − 1997	z=4.897
PC 1158+4635	Quasar	1989 − 1991	z=4.73
Q0051-279	Quasar	1987 − 1989	z=4.43
Q0000-26  (QSO B0000-26)	Quasar	1987	z=4.11
PC 0910+5625  (QSO B0910+5625)	Quasar	1987	z=4.04	This was the second quasar discovered with a redshift over 4.
Q0046–293  (QSO J0048-2903)	Quasar	1987	z=4.01
Q1208+1011  (QSO B1208+1011)	Quasar	1986 − 1987	z=3.80	This is a gravitationally-lensed double-image quasar, and at the time of discovery to 1991, had the least angular separation between images, 0.45 ″.
PKS 2000-330 PKS 2000-330 PKS 2000-330 is a quasar located in the constellation Sagittarius. When identified in 1982, it was the most distant and most luminous object known.-Distance measurements:...   (QSO J2003-3251, Q2000-330)	Quasar	1982 − 1986	z=3.78
OQ172  (QSO B1442+101)	Quasar	1974 − 1982	z=3.53
OH471  (QSO B0642+449)	Quasar	1973 − 1974	z=3.408	Nickname was "the blaze marking the edge of the universe".
4C 05.34	Quasar	1970 − 1973	z=2.877	Its redshift was so much greater than the previous record that it was believed to be erroneous, or spurious.
5C 02.56  (7C 105517.75+495540.95)	Quasar	1968 − 1970	z=2.399
4C 25.05  (4C 25.5)	Quasar	1968	z=2.358
PKS 0237-23  (QSO B0237-2321)	Quasar	1967 − 1968	z=2.225
4C 12.39  (Q1116+12, PKS 1116+12)	Quasar	1966 − 1967	z=2.1291
4C 01.02  (Q0106+01, PKS 0106+1)	Quasar	1965 − 1966	z=2.0990
3C 9 3C 9 3C 9 is a lobe-dominated quasar located in the constellation Pisces.In 1965, it was the most distant object discovered at the time of discovery. This was the first quasar with a redshift in excess of 2.-External links:* Wikisky of 3C 9...	Quasar	1965	z=2.018
3C 147 3C 147 3C 147 is a compact steep-spectrum quasar that was discovered in 1964. It is located in the constellation Auriga not far in the sky from the 5th magnitude star Omicron Aurigae....	Quasar	1964 − 1965	z=0.545
3C 295 3C 295 3C 295 is a narrow-line radio galaxy located in the constellation of Boötes. With a redshift of 0.464, it is approximately 5 billion light-years from Earth...	Radio galaxy Radio galaxy Radio galaxies and their relatives, radio-loud quasars and blazars, are types of active galaxy that are very luminous at radio wavelengths, with luminosities up to 1039 W between 10 MHz and 100 GHz. The radio emission is due to the synchrotron process...	1960 − 1964	z=0.461
LEDA 25177 (MCG+01-23-008)	Brightest cluster galaxy Brightest cluster galaxy Brightest cluster galaxy is defined as the brightest galaxy in a cluster of galaxies. BCGs include the most massive galaxies in the universe. They are generally elliptical galaxies which lie close to the geometric and kinematical center of their host galaxy cluster, hence at the bottom of the...	1951 − 1960	z=0.2 (V=61000 km/s)	This galaxy lies in the Hydra Supercluster. It is located at B1950.0  and is the BCG of the fainter Hydra Cluster Cl 0855+0321 (ACO 732).
LEDA 51975 (MCG+05-34-069)	Brightest cluster galaxy	1936 -	z=0.13 (V=39000 km/s)	The brightest cluster galaxy Brightest cluster galaxy Brightest cluster galaxy is defined as the brightest galaxy in a cluster of galaxies. BCGs include the most massive galaxies in the universe. They are generally elliptical galaxies which lie close to the geometric and kinematical center of their host galaxy cluster, hence at the bottom of the...  of the Bootes cluster (ACO 1930), an elliptical galaxy at B1950.0  apparent magnitude Apparent magnitude The apparent magnitude of a celestial body is a measure of its brightness as seen by an observer on Earth, adjusted to the value it would have in the absence of the atmosphere...  17.8, was found by Milton L. Humason Milton L. Humason Milton Lasell Humason was an American astronomer. He was born in Dodge Center, Minnesota.He dropped out of school and had no formal education past the age of 14. Because he loved the mountains, and Mount Wilson in particular, he became a "mule skinner" taking materials and equipment up the...  in 1936 to have a 40,000 km/s recessional redshift velocity.
LEDA 20221 (MCG+06-16-021)	Brightest cluster galaxy	1932 -	z=0.075 (V=23000 km/s)	This is the BCG of the Gemini Cluster (ACO 568) and was located at B1950.0
BCG of WMH Christie's Leo Cluster	Brightest cluster galaxy	1931 − 1932	z= (V=19700 km/s)
BCG of Baede's Ursa Major Cluster	Brightest cluster galaxy	1930 − 1931	z= (V=11700 km/s)
NGC 4860	Galaxy	1929 − 1930	z=0.026 (V=7800 km/s)
NGC 7619	Galaxy	1929	z=0.012 (V=3779 km/s)	Using redshift measurements, NGC 7619 was the highest at the time of measurement. At the time of announcement, it was not yet accepted as a general guide to distance, however, later in the year, Edwin Hubble described redshift in relation to distance, which became accepted widely as an inferred distance.
NGC 584 NGC 584 NGC 584 is an elliptical galaxy in the constellation Cetus. The galaxy was discovered on 10 September 1785 by the German-British astronomer William Herschel.-External links:*...   (Dreyer nebula 584)	Galaxy	1921 − 1929	z=0.006 (V=1800 km/s)	At the time, nebula had yet to be accepted as independent galaxies. However, in 1923, galaxies were generally recognized as external to the Milky Way.
M104 Sombrero Galaxy The Sombrero Galaxy is an unbarred spiral galaxy in the constellation Virgo located 28 million light years from earth. It has a bright nucleus, an unusually large central bulge, and a prominent dust lane in its inclined disk. The dark dust lane and the bulge give this galaxy the appearance of a...  (NGC 4594)	Galaxy	1913 − 1921	z=0.004 (V=1180 km/s)	This was the second galaxy whose redshift was determined; the first being Andromeda - which is approaching us and thus cannot have its redshift used to infer distance. Both were measured by Vesto Melvin Slipher. At this time, nebula had yet to be accepted as independent galaxies. NGC 4594 was measured originally as 1000 km/s, then refined to 1100, and then to 1180 in 1916.
Arcturus  (Alpha Bootis)	Star Star A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...	1891 − 1910	160 ly  (18 mas) (this is very inaccurate)	This number is wrong; originally announced in 1891, the figure was corrected in 1910 to 40 ly (60 mas). From 1891 to 1910, it had been thought this was the star with the smallest known parallax, hence the most distant star whose distance was known. Prior to 1891, Arcturus had previously been recorded of having a parallax of 127 mas.
Capella Capella (star) Capella is the brightest star in the constellation Auriga, the sixth brightest star in the night sky and the third brightest star in the northern celestial hemisphere, after Arcturus and Vega. Although it appears to be a single star to the naked eye, it is actually a star system of four stars in...   (Alpha Aurigae)	Star Star A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...	1849 -	72 ly (46 mas)
Polaris Polaris Polaris |Alpha]] Ursae Minoris, commonly North Star or Pole Star, also Lodestar) is the brightest star in the constellation Ursa Minor. It is very close to the north celestial pole, making it the current northern pole star....   (Alpha Ursae Minoris)	Star	1847 - 1849	50 ly (80 mas) (this is very inaccurate)
Vega Vega Vega is the brightest star in the constellation Lyra, the fifth brightest star in the night sky and the second brightest star in the northern celestial hemisphere, after Arcturus...   (Alpha Lyrae)	Star (part of a double star Double star In observational astronomy, a double star is a pair of stars that appear close to each other in the sky as seen from Earth when viewed through an optical telescope. This can happen either because the pair forms a binary star, i.e...  pair)	1839 - 1847	7.77 pc (125 mas)
61 Cygni 61 Cygni 61 Cygni,Not to be confused with 16 Cygni, a more distant system containing two G-type stars harboring the gas giant planet 16 Cygni Bb. sometimes called Bessel's Star or Piazzi's Flying Star, is a binary star system in the constellation Cygnus...	Binary star Binary star A binary star is a star system consisting of two stars orbiting around their common center of mass. The brighter star is called the primary and the other is its companion star, comes, or secondary...	1838 − 1839	3.48 pc Parsec The parsec is a unit of length used in astronomy. It is about 3.26 light-years, or just under 31 trillion kilometres ....   (313.6 mas)	This was the first star other than the Sun to have its distance measured.
Uranus Uranus Uranus is the seventh planet from the Sun. It has the third-largest planetary radius and fourth-largest planetary mass in the Solar System. It is named after the ancient Greek deity of the sky Uranus , the father of Cronus and grandfather of Zeus...	Planet Planet A planet is a celestial body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.The term planet is ancient, with ties to history, science,...  of the Solar System	1781 − 1838	18 AU Astronomical unit An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....	This was the last planet discovered before the first successful measurement of stellar parallax. It had been determined that the stars were much farther away than the planets.
Saturn Saturn Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Saturn is named after the Roman god Saturn, equated to the Greek Cronus , the Babylonian Ninurta and the Hindu Shani. Saturn's astronomical symbol represents the Roman god's sickle.Saturn,...	Planet of the Solar System	1619 − 1781	10 AU	From Kepler's Third Law Kepler's laws of planetary motion In astronomy, Kepler's laws give a description of the motion of planets around the Sun.Kepler's laws are:#The orbit of every planet is an ellipse with the Sun at one of the two foci.... , it was finally determined that Saturn is indeed the outermost of the classical planets, and its distance derived. It had only previously been conjectured to be the outermost, due to it having the longest orbital period, and slowest orbital motion. It had been determined that the stars were much farther away than the planets.
Mars Mars Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...	Planet of the Solar System	1609 − 1619	2.6 AU when Mars is diametrically opposed to Earth	Kepler correctly characterized Mars and Earth's orbits in the publication Astronomia nova Astronomia nova The Astronomia nova is a book, published in 1609, that contains the results of the astronomer Johannes Kepler's ten-year long investigation of the motion of Mars... . It had been conjectured that the fixed stars were much farther away than the planets.
Sun Sun The Sun is the star at the center of the Solar System. It is almost perfectly spherical and consists of hot plasma interwoven with magnetic fields...	Star	3rd century BCE — 1609	1 AU (An AU is the measurement of the average distance between the Sun and the Earth	Aristarchus of Samos Aristarchus of Samos Aristarchus, or more correctly Aristarchos , was a Greek astronomer and mathematician, born on the island of Samos, in Greece. He presented the first known heliocentric model of the solar system, placing the Sun, not the Earth, at the center of the known universe...  made a measurement of the distance of the Sun from the Earth in relation to the distance of the Moon from the Earth. The distance to the Moon was described in Earth radii (20, also inaccurate). The diameter of the Earth had been calculated previously. At the time, it was assumed that some of the planets were further away, but their distances could not be measured. The order of the planets was conjecture until Kepler determined the distances of the four true planets from the Sun that were not Earth. It had been conjectured that the fixed stars were much farther away than the planets.
z represents redshift Redshift In physics , redshift happens when light seen coming from an object is proportionally increased in wavelength, or shifted to the red end of the spectrum... , a measure of recessional velocity and inferred distance due to cosmological expansion mas represents parallax Parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight, and is measured by the angle or semi-angle of inclination between those two lines. The term is derived from the Greek παράλλαξις , meaning "alteration"... , a measure of angle and distance can be determined through trigonometry

List of most distant objects by year of object discovery

This list contains a list of most distant objects by year of discovery of the object, not the determination of its distance. Objects may have been discovered without distance determination, and were found subsequently to be the most distant known at that time.

Farthest known astronomical objects per year of record

Year of record	Distance (Mly)	Object	Type	Detected using	First record by (1)
964	2.5	Andromeda Galaxy Andromeda Galaxy The Andromeda Galaxy is a spiral galaxy approximately 2.5 million light-years from Earth in the constellation Andromeda. It is also known as Messier 31, M31, or NGC 224, and is often referred to as the Great Andromeda Nebula in older texts. Andromeda is the nearest spiral galaxy to the...	Spiral galaxy Spiral galaxy A spiral galaxy is a certain kind of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae and, as such, forms part of the Hubble sequence. Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as...	naked eye	Abd al-Rahman al-Sufi
1654	3	Triangulum Galaxy Triangulum Galaxy The Triangulum Galaxy is a spiral galaxy approximately 3 million light years from Earth in the constellation Triangulum. It is catalogued as Messier 33 or NGC 598, and is sometimes informally referred to as the Pinwheel Galaxy, a nickname it shares with Messier 101...	Spiral galaxy Spiral galaxy A spiral galaxy is a certain kind of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae and, as such, forms part of the Hubble sequence. Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as...	refracting telescope	Giovanni Battista Hodierna Giovanni Battista Hodierna Giovanni Battista Hodierna was an Italian astronomer at the court of the Duke of Montechiaro. He compiled a catalog of some 40 entries, including at least 19 real and verifiable nebulous objects that might be confused with comets. The work anticipated Messier's catalogue, but had little impact...
1779	68	Messier 58 Messier 58 Messier 58 is a barred spiral galaxy located within the constellation Virgo, approximately 68 million light-years away from Earth. It was discovered by Charles Messier on April 15, 1779 and is one of four barred spiral galaxies that appear in Messier's catalogue. M58 is one of the brightest...	Barred spiral galaxy Barred spiral galaxy A barred spiral galaxy is a spiral galaxy with a central bar-shaped structure composed of stars. Bars are found in approximately two-thirds of all spiral galaxies...	refracting telescope Refracting telescope A refracting or refractor telescope is a type of optical telescope that uses a lens as its objective to form an image . The refracting telescope design was originally used in spy glasses and astronomical telescopes but is also used for long focus camera lenses...	Charles Messier Charles Messier Charles Messier was a French astronomer most notable for publishing an astronomical catalogue consisting of deep sky objects such as nebulae and star clusters that came to be known as the 110 "Messier objects"...
1880s	206 ± 29	NGC 1 NGC 1 NGC 1 is a spiral galaxy located 190 million light-years away in the constellation Pegasus. At about 90,000 light-years in diameter, it is just a little smaller than our galaxy, the Milky Way. It is the first object listed in the New General Catalogue...	Spiral galaxy Spiral galaxy A spiral galaxy is a certain kind of galaxy originally described by Edwin Hubble in his 1936 work The Realm of the Nebulae and, as such, forms part of the Hubble sequence. Spiral galaxies consist of a flat, rotating disk containing stars, gas and dust, and a central concentration of stars known as...		Dreyer, Herschel William Herschel Sir Frederick William Herschel, KH, FRS, German: Friedrich Wilhelm Herschel was a German-born British astronomer, technical expert, and composer. Born in Hanover, Wilhelm first followed his father into the Military Band of Hanover, but emigrated to Britain at age 19...
1959	2,400	3C 273	Quasar Quasar A quasi-stellar radio source is a very energetic and distant active galactic nucleus. Quasars are extremely luminous and were first identified as being high redshift sources of electromagnetic energy, including radio waves and visible light, that were point-like, similar to stars, rather than...	Parkes Radio Telescope	Maarten Schmidt Maarten Schmidt Maarten Schmidt is a Dutch astronomer who measured the distances of quasars.Born in Groningen, The Netherlands, Schmidt studied with Jan Hendrik Oort. He earned his Ph.D. degree from Leiden Observatory in 1956.... , Bev Oke
1960	5,000	3C 295 3C 295 3C 295 is a narrow-line radio galaxy located in the constellation of Boötes. With a redshift of 0.464, it is approximately 5 billion light-years from Earth...	Radio galaxy Radio galaxy Radio galaxies and their relatives, radio-loud quasars and blazars, are types of active galaxy that are very luminous at radio wavelengths, with luminosities up to 1039 W between 10 MHz and 100 GHz. The radio emission is due to the synchrotron process...	Palomar Observatory Palomar Observatory Palomar Observatory is a privately owned observatory located in San Diego County, California, southeast of Pasadena's Mount Wilson Observatory, in the Palomar Mountain Range. At approximately elevation, it is owned and operated by the California Institute of Technology...	Rudolph Minkowski Rudolph Minkowski Rudolph Minkowski was a German-American astronomer. His father was the physiologist Oskar Minkowski and his uncle was Hermann Minkowski....
2009	13,000	GRB 090423 GRB 090423 GRB 090423 is a gamma-ray burst detected by the Swift Gamma-Ray Burst Mission on April 23, 2009 at 07:55:19 UTC. The afterglow of GRB 090423 was detected in the infrared, and allowed astronomers to determine that the redshift of GRB 090423 is z = 8.2, which makes GRB 090423 the second...	Gamma-ray burst progenitor	Swift Gamma-Ray Burst Mission Swift Gamma-Ray Burst Mission The Swift Gamma-Ray Burst Mission consists of a robotic spacecraft called Swift, which was launched into orbit on 20 November 2004, 17:16:00 UTC on a Delta II 7320-10C expendable launch vehicle. Swift is managed by the NASA Goddard Space Flight Center, and was developed by an international...	Krimm, H. et al.

⁽¹⁾: Object must have been named or described. Objects like OJ 287

OJ 287

OJ 287 is a BL Lac object located 3.5 billion light years away that has produced quasi-periodic optical outbursts going back approximately 120 years, as first apparent on photographic plates from 1891...

are ignored, because though they were detected as early as 1891 using photographic plates, they were ignored until the advent of radiotelescopes.