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GLASS-z12
GLASS-z12 is a candidate Lyman-break galaxy discovered by the Grism Lens-Amplified Survey from Space (GLASS) observing program using the James Webb Space Telescope in July 2022. It is currently one of the earliest and most distant galaxies ever discovered, dating back to just 350 million years after the Big Bang, 13.6 billion years ago. GLASS-z12 derives its name from the GLASS survey that discovered it and its estimated redshift of approximately z = . GLASS-z12 was initially announced as ''GLASS-z13'' because it was thought to have a higher redshift of z = 13.1. This redshift value was later revised down to z = 12.4 in October 2022, resulting in the renaming of this galaxy. GLASS-z12 has a light-travel distance (lookback time) of 13.6 billion years. However, due to the expansion of the universe, its present proper distance is 33.2 billion light-years. It was discovered alongside another galaxy, GLASS-z10, comparable to GN-z11, also one of the oldest galaxies discovered. Spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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. 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. The former is generally both more precise and also more reliable, in the sense that photometric redshifts are more prone to being wrong due to confusion with lower redshift sources that may have unusual spectra. For that reason, a spectroscopic redshift is conventio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD1 (galaxy)
HD1 is a proposed high-redshift galaxy, and is considered, as of April 2022, to be one of the earliest and most distant known galaxies yet identified in the observable universe. The galaxy, with an estimated redshift of approximately z = 13.27, is seen as it was about 324 million years after the Big Bang, 13.787 billion years ago. It has a light-travel distance (lookback time) of 13.463 billion light-years from Earth, and, due to the expansion of the universe, a present proper distance of 33.288 billion light-years. KEMP Cosmology Calculator - Set H0=67.4 and OmegaM=0.315 (see Table/Planck2018 at " Lambda-CDM model#Parameters") Discovery The discovery of the proposed high-redshift galaxy HD1 ( RA:10:01:51.31 DEC:+02:32:50.0) in the Sextans constellation, along with another high-redshift galaxy, HD2 ( RA:02:18:52.44 DEC:-05:08:36.1) in the Cetus constellation, was reported by astronomers at the University of Tokyo on 7 April 2022. These two galaxies were found in two p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 observed. CEERS-93316 would have a light-travel distance (lookback time) of 13.7 billion years, and, due to the expansion of the universe, a present proper distance of 34.9 billion light-years. (H0=67.4 and OmegaM=0.315 (see Table/Planck2018 at " Lambda-CDM model#Parameters" ) Discovery The candidate high-redshift galaxy CEERS-93316 ( RA:14:19:39.48 DEC:+52:56:34.92), in the Boötes constellation, was discovered by the CEERS imaging observing program using the Near Infrared Camera of the James Webb Space Telescope (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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lyman-break Galaxy
Lyman-break galaxies are star-forming galaxies at high redshift that are selected using the differing appearance of the galaxy in several imaging filters due to the position of the Lyman limit. The technique has primarily been used to select galaxies at redshifts of ''z'' = 3–4 using ultraviolet and optical filters, but progress in ultraviolet astronomy and in infrared astronomy has allowed the use of this technique at lower and higher redshifts using ultraviolet and near-infrared filters. The Lyman-break galaxy selection technique relies on the fact that radiation at higher energies than the Lyman limit at 912 Å is almost completely absorbed by neutral gas around star-forming regions of galaxies. In the rest frame of the emitting galaxy, the emitted spectrum is bright at wavelengths longer than 912 Å, but very dim or imperceptible at shorter wavelengths—this is known as a " dropout", or "break", and can be used to find the position of the Lyman limit. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GN-z11
GN-z11 is a high-redshift galaxy found in the constellation Ursa Major. 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, having a spectroscopic redshift 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 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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 Space Telescope. This will enable investigations across many fields of astronomy and cosmology, such as observation of the first stars, the formation of the first galaxies, and detailed atmospheric characterization of potentially habitable exoplanets. The U.S. National Aeronautics and Space Administration (NASA) led JWST's design and development and partnered with two main agencies: the European Space Agency (ESA) and the Canadian Space Agency (CSA). The NASA Goddard Space Flight Center (GSFC) in Maryland managed telescope development, the Space Telescope Science Institute in Baltimore on the Homewood Campus of Johns Hopkins University operates JWST, and the prime contractor was Northrop Grumman. The telescope is named after James E. Webb, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lambda-CDM Model
The ΛCDM (Lambda cold dark matter) or Lambda-CDM model is a parameterization of the Big Bang cosmological model in which the universe contains three major components: first, a cosmological constant denoted by Lambda (Greek Λ) associated with dark energy; second, the postulated cold dark matter (abbreviated CDM); and third, ordinary matter. It is frequently referred to as the ''standard model'' of Big Bang cosmology because it is the simplest model that provides a reasonably good account of the following properties of the cosmos: * the existence and structure of the cosmic microwave background * the large-scale structure in the distribution of galaxies * the observed abundances of hydrogen (including deuterium), helium, and lithium * the accelerating expansion of the universe observed in the light from distant galaxies and supernovae The model assumes that general relativity is the correct theory of gravity on cosmological scales. It emerged in the late 1990s as a concord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
JADES-GS-z13-0
JADES-GS-z13-0 is a high-redshift Lyman-break galaxy discovered by the James Webb Space Telescope (JWST) during NIRCam imaging for the JWST Advanced Deep Extragalactic Survey (JADES) on 29 September 2022. Spectroscopic observations by JWST's NIRSpec instrument in October 2022 confirmed the galaxy's redshift of ''z'' = 13.2 to a high accuracy, establishing it as the oldest and most distant spectroscopically-confirmed galaxy known , with a light-travel distance (lookback time) of 13.6 billion years. Due to the expansion of the universe, its present proper distance is 33.6 billion light-years. JADES-GS-z13-0 is located in the Great Observatories Origins Deep Survey – South (GOODS-S) field in the constellation Fornax, which includes the Hubble Ultra Deep Field. See also * 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 comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Earliest Galaxies
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. Galaxies, averaging an estimated 100 million stars, range in size from dwarfs with less than a hundred million stars, to the largest galaxies known – supergiants with one hundred trillion stars, each orbiting its galaxy's center of mass. Most of the mass in a typical galaxy is in the form of dark matter, with only a few percent of that mass visible in the form of stars and nebulae. Supermassive black holes are a common feature at the centres of galaxies. Galaxies are categorized according to their visual morphology as elliptical, spiral, or irregular. Many are thought to have supermassive black holes at their centers. The Milky Way's central black hole, known as Sagittarius A*, has a mass four million times greater than the Sun. As of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Doubly Ionized Oxygen
In astronomy and atomic physics, doubly ionized oxygen is the ion O2+ (O III in spectroscopic notation). Its emission forbidden lines in the visible spectrum fall primarily at the wavelength 500.7 nm, and secondarily at 495.9 nm. Before spectra of oxygen ions became known, these lines once led to a spurious identification of the substance as a new chemical element. Concentrated levels of O III are found in diffuse and planetary nebulae. Consequently, narrow band-pass filters that isolate the 500.7 nm and 495.9 nm wavelengths of light, that correspond to green-turquoise-cyan spectral colors, are useful in observing these objects, causing them to appear at higher contrast against the filtered and consequently blacker background of space (and possibly light-polluted terrestrial atmosphere) where the frequencies of IIIare much less pronounced. These emission lines were first discovered in the spectra of planetary nebulae in the 1860s. At that time, they were th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
