An ultra diffuse galaxy (UDG), or Dark galaxy,[1] is an extremely low luminosity galaxy, the first example of which was discovered in the nearby Virgo Cluster by Allan Sandage and Bruno Binggeli in 1984.[a] These galaxies have been studied for many years prior to their renaming in 2015. Their lack of luminosity is due to the lack of star-forming gas, which results in these galaxies being reservoirs of very old stellar populations.[3][4]
Based on discoveries confirmed in 2018, this class of galaxies includes both extremes of dark matter content: Some UDGs consist almost entirely of dark matter (such a galaxy may have the same size and mass as the Milky Way but a visible star count of only 1%),[5] while other UDGs appear to be almost entirely free of dark matter.[6]
^Overbye, Dennis (26 January 2024). "What Do You Call a Galaxy Without Stars? - To dark matter and dark energy, add dark galaxies — collections of stars so sparse and faint that they are all but invisible". The New York Times. Archived from the original on 26 January 2024.
^Conselice, Christopher J. (March 2018). "Ultra-diffuse galaxies are a subset of cluster dwarf elliptical/spheroidal galaxies". Research Notes of the AAS. 2 (1): 43. arXiv:1803.06927. Bibcode:2018RNAAS...2...43C. doi:10.3847/2515-5172/aab7f6. ISSN 2515-5172. S2CID 55462455.
^Cite error: The named reference ScienceDaily-2015-06-22 was invoked but never defined (see the help page).
^Cite error: The named reference Phys.org-2015-05-14 was invoked but never defined (see the help page).
^Cite error: The named reference NS-20160825 was invoked but never defined (see the help page).
^Cite error: The named reference vanDokkum2018 was invoked but never defined (see the help page).
Cite error: There are <ref group=lower-alpha> tags or {{efn}} templates on this page, but the references will not show without a {{reflist|group=lower-alpha}} template or {{notelist}} template (see the help page).
and 26 Related for: Ultra diffuse galaxy information
An ultradiffusegalaxy (UDG), or Dark galaxy, is an extremely low luminosity galaxy, the first example of which was discovered in the nearby Virgo Cluster...
astronomers reported that Dragonfly 44, an ultradiffusegalaxy (UDG) with the mass of the Milky Way galaxy, but with nearly no discernible stars or galactic...
Dragonfly 44 is an ultradiffusegalaxy in the Coma Cluster. This galaxy is well-known because observations of the velocity dispersion in 2016 suggested...
DGSAT I is a quenched, ultradiffusegalaxy (UDG) located on the outskirts of the Pisces-Perseus Supercluster, identified in 2016 during a visual inspection...
A low-surface-brightness galaxy, or LSB galaxy, is a diffusegalaxy with a surface brightness that, when viewed from Earth, is at least one magnitude lower...
of (dwarf) irregular galaxies include the Magellanic Clouds. A dark or "ultradiffuse" galaxy is an extremely-low-luminosity galaxy. It may be the same...
brightness of any galaxy discovered and is ~ 100 times more diffuse than any known ultradiffusegalaxy. The large size of the galaxy suggests that it...
cluster of galaxies yet discovered. The massive cD galaxy Holmberg 15A is also found in Cetus; as is spiral galaxy NGC 1042 and ultra-diffusegalaxy NGC 1052-DF2...
detection of 89 candidate ultra-diffusegalaxies (UDGs), around NGC 7609 and HCG 95, in which one is linked with. It is a gas-rich galaxy with H i mass 1.1 x...
– Astronomers report that Dragonfly 44, an ultradiffusegalaxy (UDG) with the mass of the Milky Way galaxy, but with nearly no discernable stars or galactic...
truncated—possibly by an encounter with another galaxy. Its interstellar medium consists of diffuse gas enriched by elements emitted from evolved stars...
(13 April 2016). "The feeble giant. Discovery of a large and diffuse Milky Way dwarf galaxy in the constellation of Crater". Monthly Notices of the Royal...
The Milky Way is the galaxy that includes the Solar System, with the name describing the galaxy's appearance from Earth: a hazy band of light seen in the...
following is a list of notable galaxies. There are about 51 galaxies in the Local Group (see list of nearest galaxies for a complete list), on the order...
non-spherically symmetric systems, such as the Bullet Cluster. Some ultradiffusegalaxies, such as NGC 1052-DF2, appear to be free of dark matter. If this...
Triangulum Galaxy's brightest and largest H II region (diffuse emission nebula containing ionized hydrogen) as H III.150 separately from the galaxy itself;...
K.; Romanowsky, A. J. (May 2017). "The HI content of isolated ultra-diffusegalaxies: A sign of multiple formation mechanisms?". Astronomy & Astrophysics...
The Samsung Galaxy S7, Samsung Galaxy S7 Edge and Samsung Galaxy S7 Active are Android-based smartphones manufactured, released and marketed by Samsung...
cosmological expansion. Initially, it was estimated that there may be 2 trillion galaxies in the observable universe. That number was reduced in 2021 to only several...
uracils from DNA Double-stranded uracil-DNA glycosylase, an enzyme Ultradiffusegalaxy Unit disk graph from geometric graph theory udg, the ISO 639-3 code...
place: Finding dwarf galaxies is an extremely difficult task, since they tend to have low surface brightness and are highly diffuse – so much so that they...
of host galaxies, globular clusters should not be mistaken for satellite galaxies. Satellite galaxies are not only more extended and diffuse compared...
Interacting galaxies (colliding galaxies) are galaxies whose gravitational fields result in a disturbance of one another. An example of a minor interaction...
Michael; Wright, Anna (2021). "An excess of globular clusters in Ultra-DiffuseGalaxies formed through tidal heating". Monthly Notices of the Royal Astronomical...
Global Information