GN-z11 is a
high-redshift galaxy
A galaxy is a system of stars, stellar remnants, interstellar gas, dust, dark matter, bound together by gravity. The word is derived from the Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. ...
found in the constellation
Ursa Major
Ursa Major (; also known as the Great Bear) is a constellation in the northern sky, whose associated mythology likely dates back into prehistory. Its Latin name means "greater (or larger) bear," referring to and contrasting it with nearby Ursa ...
. It is one of the farthest known galaxies from Earth ever discovered.
The 2015 discovery was published in a 2016 paper headed by Pascal Oesch and Gabriel Brammer (Cosmic Dawn Center). Up until the discovery of
HD1 in 2022, GN-z11 was the oldest and
most distant known galaxy yet identified in the
observable universe
The observable universe is a ball-shaped region of the universe comprising all matter that can be observed from Earth or its space-based telescopes and exploratory probes at the present time, because the electromagnetic radiation from these obj ...
,
having a
spectroscopic
Spectroscopy is the field of study that measures and interprets the electromagnetic spectra that result from the interaction between electromagnetic radiation and matter as a function of the wavelength or frequency of the radiation. Matter wa ...
redshift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in f ...
of , which corresponds to a
proper distance of approximately .
[At first glance, the distance of might seem impossibly far away in a Universe that is only 13.8 billion (short scale) years old, where a light-year is the distance light travels in a year, and where nothing can travel faster than the speed of light. However, because of the ]expansion of the universe
The expansion of the universe is the increase in distance between any two given gravitationally unbound parts of the observable universe with time. It is an intrinsic expansion whereby the scale of space itself changes. The universe does not exp ...
, the distance of 2.66 billion light-years between GN-z11 and the Milky Way at the time when the light was emitted increased by a factor of (z+1)=12.1 to a distance of 32.2 billion light-years during the 13.4 billion years it has taken the light to reach us. See: Size of the observable universe
The observable universe is a ball-shaped region of the universe comprising all matter that can be observed from Earth or its space-based telescopes and exploratory probes at the present time, because the electromagnetic radiation from these obj ...
, Misconceptions about the size of the observable universe, Measuring distances in expanding space, and Ant on a rubber rope
The ant on a rubber rope is a mathematical puzzle with a solution that appears counterintuitive or paradoxical. It is sometimes given as a worm, or inchworm, on a rubber or elastic band, but the principles of the puzzle remain the same.
The det ...
.
The object's name is derived from its location in the
GOODS-North field of galaxies and its high
cosmological
Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', and in 1731 taken up in Latin by German philosopher ...
redshift number .
It is observed as it existed 13.4 billion years ago, just 400 million years after the
Big Bang
The Big Bang event is a physical theory that describes how the universe expanded from an initial state of high density and temperature. Various cosmological models of the Big Bang explain the evolution of the observable universe from the ...
;
as a result, its distance is sometimes inappropriately
reported as 13.4 billion light-years, its
light-travel distance measurement.
The galaxy has such a high redshift that its
angular diameter distance is actually less than that of some galaxies with lower redshift. This means that the ratio of its angular size to its size in light-years is greater.
Discovery
The galaxy was identified by a team studying data from the
Hubble Space Telescope
The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versa ...
's
Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey
The Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey (CANDELS) is the largest project in the history of the Hubble Space Telescope, with 902 assigned orbits (about 60 continuous days) of observing time. It was carried out between 201 ...
(CANDELS) and
Spitzer Space Telescope
The Spitzer Space Telescope, formerly the Space Infrared Telescope Facility (SIRTF), was an infrared space telescope launched in 2003. Operations ended on 30 January 2020. Spitzer was the third space telescope dedicated to infrared astronomy, f ...
's
Great Observatories Origins Deep Survey
The Great Observatories Origins Deep Survey, or GOODS, is an astronomical survey combining deep observations from three of NASA's Great Observatories: the Hubble Space Telescope, the Spitzer Space Telescope, and the Chandra X-ray Observatory, al ...
-North (GOODS-North).
The research team used Hubble's
Wide Field Camera 3
The Wide Field Camera 3 (WFC3) is the Hubble Space Telescope's last and most technologically advanced instrument to take images in the visible spectrum. It was installed as a replacement for the Wide Field and Planetary Camera 2 during the first ...
to measure the distance to GN-z11
spectroscopically, measuring the
redshift
In physics, a redshift is an increase in the wavelength, and corresponding decrease in the frequency and photon energy, of electromagnetic radiation (such as light). The opposite change, a decrease in wavelength and simultaneous increase in f ...
caused by the
expansion of the universe
The expansion of the universe is the increase in distance between any two given gravitationally unbound parts of the observable universe with time. It is an intrinsic expansion whereby the scale of space itself changes. The universe does not exp ...
.
The findings, which were announced in March 2016, revealed the galaxy to be farther away than originally thought, at the distance limit of what the Hubble Telescope can observe. GN-z11 is around 150 million years older than the previous record-holder
EGSY8p7
__NOTOC__
EGSY8p7 (EGSY-2008532660) is a distant galaxy in the constellation of Boötes, with a spectroscopic redshift of ''z'' = 8.68 (photometric redshift 8.57), a light travel distance of 13.2 billion light-years from Earth. Theref ...
,
and is observed (shortly after but) "very close to the end of the so-called
Dark Ages of the universe",
and (during but) "near the very beginning" of the
reionization
In the fields of Big Bang theory and cosmology, reionization is the process that caused matter in the universe to reionize after the lapse of the " dark ages".
Reionization is the second of two major phase transitions of gas in the universe (t ...
era.
Compared with the
Milky Way
The Milky Way is the galaxy that includes our Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars that cannot be individually distinguished by the naked eye ...
galaxy, GN-z11 is of the size, has 1% of the mass, and is forming new stars approximately twenty times as fast.
With a
stellar age estimated at 40 million years, it appears the galaxy formed its stars relatively rapidly.
The fact that a galaxy so massive existed so soon after the first stars started to form is a challenge to some current theoretical models of the formation of galaxies.
See also
*
CEERS-93316
CEERS-93316 is a candidate high-redshift galaxy, with an estimated redshift of approximately z = 16.4, corresponding to 236 million years after the Big Bang.
If confirmed, it would be one of the earliest and most distant known galaxies observe ...
*
GLASS-z12
*
HD1 galaxy
*
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 ...
Notes
References
{{2016 in space
20160303
Ursa Major (constellation)
Dwarf irregular galaxies