 |
List Of Resolved Circumstellar Disks
This is a list of Circumstellar disc, circumstellar disks that have published resolved images. Many of them are Protoplanetary disk, protoplanetary disks or Debris disk, debris disks. Only some are transitional disks between protoplanetary and debris. A few disks in this list are Circumstellar disc#Binary system, circumbinary disks. List of large disks This list contains disks with a diameter larger or equal to 2arcseconds and is sorted after their diameter in arcsecs. List of small disks There are hundreds of small resolved disks. This list only contains a selection of disks with d<2 arcsec. {, class="wikitable sortable" , + !Name !Image !RA (J2000) !Dec (J2000) !Distance (Light-year, lys) !Host Stellar classification, spectral type !Diameter (Minute and second of arc, arcsec) !Diameter (Astronomical unit, AU) !Inclination (°) !Age (Year#SI prefix multipliers, Myrs) !Type !Reference , - , HH-30, HH 30 , , , , 460 , M0 , 1.9 , 261 , 85 , , protoplanetary , [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
 |
Circumstellar Disc
A Circumstellar disc (or circumstellar disk) is a torus, pancake or ring-shaped accretion disk of matter composed of gas, dust, planetesimals, asteroids, or collision fragments in orbit around a star. Around the youngest stars, they are the reservoirs of material out of which planets may form. Around mature stars, they indicate that planetesimal formation has taken place, and around white dwarfs, they indicate that planetary material survived the whole of stellar evolution. Such a disc can manifest itself in various ways. Young star According to the widely accepted model of star formation, sometimes referred to as the nebular hypothesis, a young star (protostar) is formed by the gravitational collapse of a pocket of matter within a giant molecular cloud. The infalling material possesses some amount of angular momentum, which results in the formation of a gaseous protoplanetary disc around the young, rotating star. The former is a rotating circumstellar disc of dense gas and d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
 |
AU Microscopii
AU Microscopii (AU Mic) is a young red dwarf star located away – about 8 times as far as the closest star after the Sun. The apparent visual magnitude of AU Microscopii is 8.73, which is too dim to be seen with the naked eye. It was given this Variable star designation, designation because it is in the southern constellation Microscopium and is a variable star. Like Beta Pictoris, β Pictoris, AU Microscopii has a circumstellar disk of dust known as a debris disk and at least three exoplanets, with the presence of an additional planet being likely. Stellar properties AU Mic is a young star at only 22 million years old; less than 1% of the age of the Sun. With a stellar classification of M1 Ve, it is a red dwarf star with a physical radius of 75% that of the Sun. Despite being half the Sun's mass, it is radiating only 9% as much luminosity as the Sun. This energy is being emitted from the star's stellar atmosphere, outer atmosphere at an effective temperature of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
Eta Corvi
Eta Corvi (Eta Crv, η Corvi, η Crv) is an F-type star, F-type main sequence, main-sequence star, the sixth-brightest star in the constellation of Corvus (constellation), Corvus. Two debris disks have been detected orbiting this star, one at ~150 AU, and a warmer one within a few astronomical units (AU). Properties Eta Corvi is only about 30% of the Sun's age. The concentration of iron and other heavy elements in its atmosphere is only about 93% that of the Sun's. The stellar rotation, projected rotational velocity at the star's equator (''v'' sin ''i'') is 68 km/s - more than 30 times faster than that for the Sun. A yellow-white main sequence star of spectral type F2V, it has an estimated effective temperature, surface temperature of 6950 K. It is 1.52 times as massive as the Sun and is 4.87 times as luminous. It is 59 light-years distant from the Solar System. The IRAS satellite detected an infrared excess, excess of infrared radiation from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
|
HD 38858
HD 38858 is a star in the Orion constellation. It is a G-type main-sequence star, located at a distance of about 50 light-years. It has an apparent magnitude of 5.97, therefore can be seen to the naked eye only in sufficiently dark skies. The last observation of this system for a dust disc or comet belt was in 2009 by the Spitzer Space Telescope; a belt was inferred at 102 AU. citing Lawler ''et al.'' 2009, and recalculating its distance. It has an inclination of 48◦. The star exhibit a magnetic activity cycle remarkably similar to that of Sun, with the period of 10.8 years. Planetary system The exoplanet HD 38858 b was discovered in 2011 in orbit in its host star's habitable zone, a zone in which Earth-like conditions (namely the presence of liquid water) on a planet's surface are possible. The planet is likely a gas giant, a type of planet which astronomers believe is unlikely to support life as it is currently understood. However, the planet could have a rocky natu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
|
Gamma Doradus
Gamma Doradus, Latinized from γ Doradus, is the third-brightest star in the southern constellation of Dorado. It is faintly visible to the naked eye with an apparent visual magnitude of approximately 4.25, and is a variable star, the prototype of the class of Gamma Doradus variables. The star is located at a distance of 67 light years from the Sun based on parallax, and is drifting further away with a radial velocity of +25 km/s. Based on its motion through space, it appears to be a member of the IC 2391 supercluster. This is an F-type main-sequence star with a stellar classification of F1V. It is a pulsating variable that varies in brightness by less than a tenth of a magnitude owing to nonradial gravity wave oscillations. Four pulsation frequencies have been identified with periods of 17.6, 12.8, 16.3, and 18.2 hours. The star is around 0.5–1.2 billion years old and is spinning with a projected rotational velocity of 57 km/s. It has 1.6 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
|
Kappa Coronae Borealis
Kappa Coronae Borealis, Latinized from κ Coronae Borealis, is a star 98 light years away in the constellation of Corona Borealis. The apparent magnitude is +4.82 (4.17 trillion times fainter than the Sun) and the absolute magnitude is +2.35 (9.82 times brighter than the Sun). It is an orange K-type subgiant star of spectral type K1IV, meaning it has almost completely exhausted its hydrogen supply in its core. It is 1.32 times as massive as the Sun yet has brightened to 11.6 times its luminosity. Around 2.5 billion years old, it was formerly an A-type main sequence star. Dust disk In March 2013, it was announced that resolved images of at least one dust disk surrounding Kappa Coronae Borealis were captured, making it the first subgiant to host such circumstellar belt. The disk extends out from 50 AU to 180 AU, and there is an estimated 0.016 of dust. Planetary system In October 2007, a giant planet was found by Johnson et al., who used the radial velocity method. In 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
 |
Gliese 581
Gliese 581 () is a red dwarf star of spectral type M3V which hosts a planetary system, away from Earth in the constellation Libra. Its estimated mass is about a third of that of the Sun, and it is the 101st closest known star system to the Sun. Gliese 581 is one of the oldest, least active M dwarfs known. Its low stellar activity improves the likelihood of its planets retaining significant atmospheres, and lessens the sterilizing impact of stellar flares. History of observations Gliese 581 is known at least from 1886, when it was included in Eduard Schönfeld's ''Southern (SD)''—the fourth part of the '. The corresponding designation is BD -7 4003. Characteristics The name ''Gliese 581'' refers to the catalog number from the 1957 survey ''Gliese Catalogue of Nearby Stars'' of 965 stars located within 20 parsecs of the Earth. Other names of this star include ''BD-07° 4003'' ( BD catalogue, first known publication) and ''HO Librae'' (variable star designation). It d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
 |
HD 15115
HD 15115 is a single star in the equatorial constellation of Cetus. It is readily visible in binoculars or a small telescope, but is considered too dim to be seen with the naked eye at an apparent visual magnitude of 6.76. The distance to this object is 160 light years based on parallax, and it is slowly drifting further away at the rate of about 1 km/s. It has been proposed as a member of the Beta Pictoris moving group or the Tucana-Horologium association of co-moving stars; there is some ambiguity as to its true membership. This object has a stellar classification of F4IV, suggesting it is an aging subgiant star that has exhausted the supply of hydrogen at its core. MacGregor and associates (2015) instead classify it as a young F-type main-sequence star with a class of F2V. Age estimates give a value of 500 million years, while membership in the β Pictoris moving group would indicate an age of around . It has 1.19 times the mass of the Sun, 1.39 times t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
HD 207129
HD 207129 is a G-type main-sequence star in the constellation of Grus. It has an apparent visual magnitude of approximately 5.6 This is a Sun-like star with the same stellar classification G2V and a similar mass. It is roughly the same age as the Sun, but has a lower abundance of elements other than hydrogen and helium; (which astronomers refer to as the star's metallicity). A debris disk has been imaged around this star in visible light using the ACS instrument on the Hubble Space Telescope; it has also been imaged in the infrared (70 μm) using the MIPS instrument on the Spitzer Space Telescope. Based on the ACS image, the disk appears to have a radius of about 163 astronomical units and to be about 30 AU wide, and to be inclined at 60° to the plane of the sky. Another star, CCDM J21483-4718B (also designated CD−47 13929 or WDS J21483-4718B), of apparent visual magnitude 8.7, has been observed 55 arcseconds away from this star, but based on com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
|
160517 ALMAplanets2 Nrao-2
Sixteen or 16 may refer to: *16 (number) *one of the years 16 BC, AD 16, 1916, 2016 Films * ''Pathinaaru'' or ''Sixteen'', a 2010 Tamil film * ''Sixteen'' (1943 film), a 1943 Argentine film directed by Carlos Hugo Christensen * ''Sixteen'' (2013 Indian film), a 2013 Hindi film * ''Sixteen'' (2013 British film), a 2013 British film by director Rob Brown Music *The Sixteen, an English choir *16 (band), a sludge metal band *Sixteen (Polish band), a Polish band Albums * ''16'' (Robin album), a 2014 album by Robin * 16 (Madhouse album), a 1987 album by Madhouse * ''Sixteen'' (album), a 1983 album by Stacy Lattisaw *''Sixteen'' , a 2005 album by Shook Ones * ''16'', a 2020 album by Wejdene Songs * "16" (Sneaky Sound System song), 2009 * "Sixteen" (Thomas Rhett song), 2017 * "Sixteen" (Ellie Goulding song), 2019 *"Six7een", by Hori7on, 2023 *"16", by Craig David from ''Following My Intuition'', 2016 *"16", by Green Day from ''39/Smooth'', 1990 *"16", by Highly Suspect from ''MCID'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
|
 |
HR 8799
HR 8799 is a roughly 30 million-year-old main sequence, main-sequence star located away from Earth in the constellation of Pegasus (constellation), Pegasus. It has roughly 1.5 times the Sun's mass and 4.9 times its luminosity. It is part of a system that also contains a debris disk and at least four gas giant, massive planets. These planets were the first exoplanets whose orbital motion was confirmed by direct imaging. The star is a Gamma Doradus variable: its luminosity changes because of non-radial pulsations of its surface. The star is also classified as a Lambda Boötis star, which means its surface layers are depleted in iron peak Chemical element, elements. It is the only known star which is simultaneously a Gamma Doradus variable, a Lambda Boötis star, Lambda Boötis type, and a Vega-like star (a star with infrared excess, excess infrared emission caused by a circumstellar disk). Location HR 8799 is a star that is visible to the naked eye. It has ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |