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Local Group (other)
The Local Group is the galaxy group that includes the Milky Way, where Earth is located. It has a total diameter of roughly , and a total mass of the order of . It consists of two collections of galaxies in a "dumbbell" shape; the Milky Way and its satellites form one lobe, and the Andromeda Galaxy and its satellites constitute the other. The two collections are separated by about and are moving toward one another with a velocity of . The group itself is a part of the larger Virgo Supercluster, which may be a part of the Laniakea Supercluster. The exact number of galaxies in the Local Group is unknown as some are occluded by the Milky Way; however, at least 80 members are known, most of which are dwarf galaxies. The two largest members, the Andromeda and the Milky Way galaxies, are both spiral galaxies with masses of about solar masses each. Each has its own system of satellite galaxies: * The List of Andromeda's satellite galaxies, Andromeda Galaxy's satellite system consist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Messier 31
Messier may refer to: People with the surname *Ashley Messier (born 2002), Canadian ice hockey player *Charles Messier (1730–1817), French astronomer *Doug Messier (born 1936), Canadian ice hockey player and coach *Éric Messier (born 1973), Canadian ice hockey player *George Messier (1896–1933), French inventor *Jean-Marie Messier (born 1956), French businessman *Joby Messier (born 1970), Canadian ice hockey player *Marc Messier (born 1947), Canadian actor and film-maker *Mark Messier (born 1961), Canadian ice hockey player *Mary Messier (born 1952), American politician *Mitch Messier (born 1965), Canadian ice hockey player *Paul Messier (ice hockey) (born 1958), Canadian ice hockey player *Paul Arthur Messier (born 1962), American art conservator Other uses *Messier Channel in western Patagonia, Chile *Messier objects, set of 110 astronomical objects *Messier (crater) on the Moon *Messier (automobile), French car manufacturer 1925–1931 *Messier-Dowty (and succeeding com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NGC 185
NGC 185 (also known as Caldwell 18) is a dwarf spheroidal galaxy located 2.08 million light-years from Earth, appearing in the constellation Cassiopeia. It is a member of the Local Group, and is a satellite of the Andromeda Galaxy (M31). NGC 185 was discovered by William Herschel on November 30, 1787, and he cataloged it "H II.707". John Herschel observed the object again in 1833 when he cataloged it as "h 35", and then in 1864 when he cataloged it as "GC 90" within his '' General Catalogue of Nebulae and Clusters''. NGC 185 was first photographed between 1898 and 1900 by James Edward Keeler with the Crossley Reflector of Lick Observatory. Unlike most dwarf elliptical galaxies, NGC 185 contains young stellar clusters, and star formation proceeded at a low rate until the recent past. NGC 185 has an active galactic nucleus (AGN) and is usually classified as a type 2 Seyfert galaxy, though its status as a Seyfert is questioned. It is possibly the closest Seyfert galaxy to Earth, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And XXII
Andromeda XXII (Pisces VI, Triangulum I) is a low surface brightness dwarf spheroidal galaxy about away from the Sun in the constellation Pisces, of the Local Group. Andromeda XXII is located much closer in projection to M33 than M31 vs. This fact suggests that it might be the first Triangulum (M33) satellite ever discovered. However, it is currently catalogued as a satellite of Andromeda (M31).Nicolas F. Martin, Alan W. McConnachie, Mike Irwin, Lawrence M. Widrow, Annette M. N. Ferguson, Rodrigo A. Ibata, John Dubinski, Arif Babul, Scott Chapman, Mark Fardal, Geraint F. Lewis, Julio Navarro, R. Michael Rich; "PAndAS' cubs: discovery of two new dwarf galaxies in the surroundings of the Andromeda and Triangulum galaxies"; The Astrophysical Journal, Volume 705, Issue 1, pp. 758-765 (2009); ; ; ; The discovery arose from the first year data of a photometric survey of the M31/ M33 subgrouping of the Local Group by the Pan-Andromeda Archaeological Survey (PAndAS). This survey w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And XXI
Andromeda XXI (And 21, And XXI) is a moderately bright dwarf spheroidal galaxy about away from the Sun in the constellation Andromeda. It is the fourth largest Local Group dwarf spheroidal galaxy. The discovery arose from the first year data of a photometric survey of the M31/ M33 subgroupings of the Local Group by the Pan-Andromeda Archaeological Survey (PAndAS). This survey was conducted with the Megaprime/MegaCam wide-field camera mounted on the Canada-France-Hawaii Telescope. This large satellite of the Andromeda Galaxy (M31) has a half-light radius of roughly 1 kpc.Nicolas F. Martin, Alan W. McConnachie, Mike Irwin, Lawrence M. Widrow, Annette M. N. Ferguson, Rodrigo A. Ibata, John Dubinski, Arif Babul, Scott Chapman, Mark Fardal, Geraint F. Lewis, Julio Navarro, R. Michael Rich; "PAndAS' cubs: discovery of two new dwarf galaxies in the surroundings of the Andromeda and Triangulum galaxies"; The Astrophysical Journal, Volume 705, Issue 1, pp. 758-765 (2009); ; ; ; And ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And XIX
Andromeda XIX is a satellite galaxy of the Andromeda Galaxy (M31), a member of the Local Group, like the Milky Way Galaxy. Andromeda XIX is considered "the most extended dwarf galaxy known in the Local Group", and has been shown to have a half-light radius of 1.7 kiloparsec The parsec (symbol: pc) is a unit of length used to measure the large distances to astronomical objects outside the Solar System, approximately equal to or (AU), i.e. . The parsec unit is obtained by the use of parallax and trigonometry, a ... (kpc). It was discovered by the Canada–France–Hawaii Telescope, and is thought to be a dwarf galaxy. As with other dwarf galaxies, Andromeda XIX is not producing new stars: 90% of its star formation occurred over 9 billion years ago. However, compared to dwarf galaxies of similar mass Andromeda XIX is extremely diffuse, like Antlia II. History Surveillance was performed during use of the MegaPrime/MegaCam 1 deg2 (camera) on the Canada-France-Hawaii Te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andromeda XI
Andromeda XI (And 11) is a dwarf spheroidal galaxy about 2.6 million light-years away from the Sun in the constellation Andromeda. Discovered in 2006, And XI is a satellite galaxy of the Andromeda Galaxy The Andromeda Galaxy is a barred spiral galaxy and is the nearest major galaxy to the Milky Way. It was originally named the Andromeda Nebula and is cataloged as Messier 31, M31, and NGC 224. Andromeda has a Galaxy#Isophotal diameter, D25 isop ... (M31). See also * List of Andromeda's satellite galaxies References {{DEFAULTSORT:Andromeda XI Andromeda (constellation) Dwarf spheroidal galaxies Astronomical objects discovered in 2006 Andromeda Subgroup Local Group ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And X
Andromeda X (And 10) is a dwarf spheroidal galaxy about 2.9 million light-years away from the Sun in the constellation Andromeda. Discovered in 2005 by Zucker et al., And X is a satellite galaxy of the Andromeda Galaxy (M31). Aided by the application of stellar photometry to data from the Sloan Digital Sky Survey similar to the Andromeda IX discovery, the new finding indicates that this type of extremely faint satellite might be common in the Local Group, potentially providing further support for hierarchical cold dark matter In cosmology and physics, cold dark matter (CDM) is a hypothetical type of dark matter. According to the current standard model of cosmology, Lambda-CDM model, approximately 27% of the universe is dark matter and 68% is dark energy, with only a sm ... models. See also * List of Andromeda's satellite galaxies References External links SEDS webpage for Andromeda X Dwarf spheroidal galaxies 5056921 Local Group Andromeda Subgroup Andromeda ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And IX
Andromeda IX (And 9) is a dwarf spheroidal satellite of the Andromeda Galaxy. It was discovered in 2004 by resolved stellar photometry from the Sloan Digital Sky Survey (SDSS), by Zucker et al. (2004). At the time of its discovery, it was the galaxy with the lowest known surface brightness, Σ''V'' ≃ 26.8mags arcsec−2 and the faintest galaxy known from its intrinsic absolute brightness. It was found from data acquired within an SDSS scan along the major axis of M31, on October 5, 2002. Its distance was estimated to be almost exactly the same as that of M31 by McConnacrchie et al. (2005). Star formation Star formation is the process by which dense regions within molecular clouds in interstellar space—sometimes referred to as "stellar nurseries" or "star-forming regions"—Jeans instability, collapse and form stars. As a branch of astronomy, sta ... history and dust production in Andromeda IX, as the closest satellite to M31, have also been investigated by Abdollahi et al ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And VIII
Andromeda VIII (And VIII / 8) is a galaxy discovered in August 2003. It is a companion galaxy to the Andromeda Galaxy, M31, and evaded detection for so long due to its diffuse nature. The galaxy was finally discovered by 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 increase in frequency and e ...s of stars in front of Andromeda, which proved to have different velocities than M31 and hence were part of a different galaxy. As of at least 2006, the actuality of And VIII as a galaxy has not yet been firmly established (Merrett et al. 2006). See also * List of Andromeda's satellite galaxies References External linksSEDS Webpage for Andromeda VIII {{DEFAULTSORT:Andromeda 08 Andromeda Subgroup Local Group Andromeda (constellation) Dwarf spheroidal galaxies 5056928 Astronomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And VII
The Cassiopeia Dwarf (also known as Andromeda VII) is a dwarf spheroidal galaxy about 2.45 Mly away in the constellation Cassiopeia. The Cassiopeia Dwarf is part of the Local Group and a satellite galaxy of the Andromeda Galaxy (M31). In the sky, it appears behind the Milky Way's galactic plane, and so it is reddened by 0.194 magnitudes. With a luminosity of and a stellar mass of , it is the brightest and most massive of the Andromeda Galaxy's dwarf spheroidal galaxy satellites. It also has the highest metallicity out of all of them. The Cassiopeia Dwarf was found in 1998, together with the Pegasus Dwarf, by a team of astronomers (Karachentsev and Karachentseva) in Russia and Ukraine. The Cassiopeia Dwarf and the Pegasus Dwarf are farther from M31 than its other known companion galaxies, yet still appear bound to it by gravity. Neither galaxy contains any young, massive stars or shows traces of recent star formation Star formation is the process by which dense regions with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And VI
The Pegasus Dwarf Spheroidal (also known as ''Andromeda VI'' or ''Peg dSph'' for short) is a dwarf spheroidal galaxy about 2.7 million light-years away in the constellation Pegasus. The Pegasus Dwarf is a member of the Local Group and a satellite galaxy of the Andromeda Galaxy (M31). General information The Pegasus Dwarf Spheroidal is a galaxy with mainly metal-poor stellar populations. Its metallicity is e/H≃ −1.3. It is located at the right ascension 23h51m46.30s and declination +24d34m57.0s in the equatorial coordinate system (epoch J2000.0), and in a distance of 820 ± 20 kpc from Earth and a distance of 294 ± 8 kpc from the Andromeda Galaxy. The galaxy was discovered in 1999 by various authors on the Second Palomar Observatory Sky Survey (POSS II) films. See also * List of Andromeda's satellite galaxies * Pegasus Dwarf Irregular Galaxy (Peg DIG) * Pegasus galaxy, the Stargate Atlantis ''Stargate Atlantis'' (usually stylized in all caps and often abbrevia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
And V
Andromeda V is a dwarf spheroidal galaxy about 2.52 Mly away in the constellation Andromeda. Andromeda V was discovered by Armandroff et al. and published in 1998 after their analysis of the digitized version of the second Palomar Sky Survey. The metallicity In astronomy, metallicity is the Abundance of the chemical elements, abundance of Chemical element, elements present in an object that are heavier than hydrogen and helium. Most of the normal currently detectable (i.e. non-Dark matter, dark) matt ... of Andromeda V is above the average metallicity to luminosity ratio of the Local Group's dwarf galaxies. See also * List of Andromeda's satellite galaxies References External links SEDS: Dwarf Spheroidal Galaxy Andromeda VSIMBAD: And V -- Galaxy {{DEFAULTSORT:Andromeda 05 Dwarf spheroidal galaxies 3097824 Local Group Andromeda Subgroup Andromeda (constellation) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
