CEERS-93316 is a candidate 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. ...

, with an estimated

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 approximately z = 16.4, corresponding to 236 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 ...

. If confirmed, it would be one of the earliest and most distant known galaxies observed. CEERS-93316 would have a light-travel distance (

lookback time Before Present (BP) years, or "years before present", is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Becau ...

) of 13.7 billion years, and, due to 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 ...

, a present proper distance of 34.9 billion light-years. (H₀=67.4 and Omega_M=0.315 (see Table/Planck2018 at " Lambda-CDM model#Parameters" )

Discovery

The candidate high-redshift

CEERS-93316 ( RA:14:19:39.48 DEC:+52:56:34.92), in the

Boötes Boötes ( ) is a constellation in the northern sky, located between 0° and +60° declination, and 13 and 16 hours of right ascension on the celestial sphere. The name comes from la, Boōtēs, which comes from grc-gre, Βοώτης, Boṓtēs ...

constellation, was discovered by the CEERS imaging observing program using the

Near Infrared Camera NIRCam (Near-InfraRed Camera) is an instrument aboard the James Webb Space Telescope. It has two major tasks, as an imager from 0.6 to 5 micron wavelength, and as a wavefront sensor to keep the 18-section mirrors functioning as one. In other wor ...

of the

James Webb Space Telescope The James Webb Space Telescope (JWST) is a space telescope which conducts infrared astronomy. As the largest optical telescope in space, its high resolution and sensitivity allow it to view objects too old, distant, or faint for the Hubble Spa ...

(JWST) in July 2022. CEERS stands for "Cosmic Evolution Early Release Science Survey", and is a deep- and wide-field sky survey program developed specifically for JWST image studies, and is conducted by the CEERS Collaboration. The galaxy's redshift was initially reported as z = 16.7 before it was revised down to z = 16.4 in October 2022. According to astronomer Dr. Rebecca Bowler, a co-author of the discovery study, “Finding a z = 16.7 'sic''galaxy candidate is an amazing feeling – it wasn’t something we were expecting from the early data ... After the Big Bang the Universe entered a period known as the dark ages, a time before any stars had been born ... The observations of EERS-93316push observations back to the time when we think the first galaxies ever to exist were being formed. Already we’ve found more galaxies in the very early Universe than computer simulations predicted, so there is clearly a lot of open questions about how and when the first stars and galaxies formed.”

Distance

Only a

photometric redshift A photometric redshift is an estimate for the recession velocity of an astronomical object such as a galaxy or quasar, made without measuring its spectrum. The technique uses photometry (that is, the brightness of the object viewed through various ...

has been determined for CEERS-93316; follow-up spectroscopic measurements will be required to confirm the redshift (see

spectroscopic 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 fr ...

). Spectroscopy could also determine the chemical composition, size and temperature of the galaxy. Its existence in the early universe indicates that it is composed primarily of dust as well as stars, most likely

population III During 1944, Walter Baade categorized groups of stars within the Milky Way into stellar populations. In the abstract of the article by Baade, he recognizes that Jan Oort originally conceived this type of classification in 1926: Baade noticed th ...

, which are very young and massive. It is also in the star formation phase. EarliestGalaxyCandidates-20220807

References

External links

CEERS WebSite

IMAGE: CEERS-93316 galaxy
(1 Aug 2022) * * {{Sky, 14, 19, 39.48, +, 52, 56, 34.92, 34684000000 Astronomical objects discovered in 2022 Boötes Galaxies

Discovery

Distance

See also

References

External links