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Debris disk around star AU Microscopii. Image taken by Hubble Space Telescope
Debris disk around star AU Microscopii. AU Microscopii (AU Mic is a Red dwarf star located 10 Parsecs (32 Light-years away -- about 8 times as far as our closest star after the Sun. Image taken by Hubble Space Telescope

A debris disk is a ring-shaped circumstellar disk of dust and debris in orbit around a star. The Hubble Space Telescope ( HST; also known colloquially as "the Hubble" or just "Hubble" is a space telescope that was carried into A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth Debris disks have been found around both evolved and young stars, as well as at least one debris disk in orbit around a neutron star. A neutron star is a type of remnant that can result from the Gravitational collapse of a massive Star during a Type II, Type Ib or Type [1] They can constitute a phase in the formation of a planetary system following the protoplanetary disk phase. A protoplanetary disk (or proplyd) is a rotating Circumstellar disk of dense gas surrounding a young newly formed star a T Tauri star or Herbig star [2] They can also be produced and maintained as the remnants of collisions between planetismals. [3]

By 2001, over 900 candidate stars have been found to possess a debris disk. They are usually located by examining the star system in infrared light and looking for an excess of radiation beyond that emitted by the star. Infrared ( IR) radiation is Electromagnetic radiation whose Wavelength is longer than that of Visible light, but shorter than that of This excess is inferred to be radiation from the star that has been absorbed by the disk, then radiated away as infrared energy. [4]

In certain cases the debris disks can be observed directly by occulting the primary star and then imaging the system.

Contents

Observation history

In 1984 a debris disk was located in orbit around the star Vega using the IRAS satellite. Vega (α Lyr / α Lyrae / Alpha Lyrae ( or) is the brightest Star in the Constellation Lyra, the fifth brightest star in the night The Infrared Astronomical Satellite ( IRAS) was the first-ever space-based Observatory to perform a survey of the entire Sky at Infrared Initially this was believed to be a protoplanetary disk, but it is now thought to be a debris disk due to the lack of gas in the disk. A protoplanetary disk (or proplyd) is a rotating Circumstellar disk of dense gas surrounding a young newly formed star a T Tauri star or Herbig star Subsequently irregularities have been found in the disk, which may be indicative of the presence of planetary bodies. [5] Similar discoveries of debris disks were made around the stars Fomalhaut and Beta Pictoris. Fomalhaut (α PsA / α Piscis Austrini / Alpha Piscis Austrini is the brightest star in the Constellation Piscis Austrinus and one of the brightest Beta Pictoris (β Pic / β Pictoris is the second brightest Star in the Constellation Pictor.

By 1998 a debris disk had been located around the nearby star 55 Cancri, a system that is also known to contain a planet. 55 Cancri (ˈkæŋkraɪ or /ˈkæŋkriː/ also catalogued Rho1 Cancri or abbreviated 55 Cnc, is a Binary star approximately 41 Light-years [6] Structures in the debris disk around Epsilon Eridani also suggest perturbations by a planetary body in orbit around that star, which may be used to constrain the mass and orbit of the planet. Epsilon Eridani (ε Eri / ε Eridani is a main-sequence K2 class Star. [7]

Origin

Typical debris disks contain small grains 1–100 μm in size. A micrometre ( American spelling: micrometer; symbol µm) is one millionth of a Metre, or equivalently one thousandth of a Millimetre Radiation from the host star can cause these particles to spiral inward because of the Poynting-Robertson effect, so the lifetime of the disk will be on the order of 10 Myr or less. Radiation, as in Physics, is Energy in the form of waves or moving Subatomic particles emitted by an atom or other body as it changes from a higher energy A star is a massive luminous ball of plasma. The nearest star to Earth is the Sun, which is the source of most of the Energy on Earth In Mathematics, a spiral is a Curve which emanates from a central point getting progressively farther away as it revolves around the point The Poynting-Robertson effect, also known as Poynting-Robertson drag, named after John Henry Poynting and Howard Percy Robertson, is a process by which This article is about the unit of time For the Magic the Gathering creatures see Creatures of Magic The Gathering. Thus, for a disk to remain intact, a process is needed to continually replenish the disk. This can occur, for example, by means of collisions between larger bodies. This can occur on a continual basis as collisions grind objects down into ever smaller bodies. [8]

For collisions to occur in a debris disk, the bodies must be gravitationally perturbed sufficiently to create relatively large collisional velocities. A planetary system around the star can cause such perturbations, as can a binary star companion or the close approach of another star. A binary star is a Star system consisting of two Stars orbiting around their Center of mass. [8]

Known belts

Belts of dust or debris have also been detected around stars other than the Sun, including the following:

Star Spectral
class[9]		 Distance
(ly)		 Orbit
(AU)
Epsilon Eridani[7] K2V 10. In Astronomy, stellar classification is a classification of Stars based initially on photospheric temperature and its associated Spectral characteristics A light-year or light year (symbol ly) is a unit of Length, equal to just under ten trillion Kilometres As defined by The astronomical unit ( AU or au or au or sometimes ua) is a unit of Length based on the distance from the Earth to the Epsilon Eridani (ε Eri / ε Eridani is a main-sequence K2 class Star. 5 35–75
Tau Ceti[10] G8V 11. Tau Ceti (τ Cet / τ Ceti ˌtaʊ ˈsiːtaɪ is a Star in the Constellation Cetus that is similar to the Sun in Mass and 9 35–50
Vega[5][11] A0V 25 86–200
AU Microscopii[12] M1Ve 33 50–150
HD 69830[13] K0V 41 <1
55 Cancri A[6] G8V 41 27–50
Pi1 Ursae Majoris[14] G1. Vega (α Lyr / α Lyrae / Alpha Lyrae ( or) is the brightest Star in the Constellation Lyra, the fifth brightest star in the night AU Microscopii (AU Mic is a Red dwarf star located 10 Parsecs (32 Light-years away -- about 8 times as far as our closest star after the Sun. HD 69830 is an Orange dwarf Star approximately 41 Light-years away in the Constellation of Puppis (the Poop Deck 55 Cancri (ˈkæŋkraɪ or /ˈkæŋkriː/ also catalogued Rho1 Cancri or abbreviated 55 Cnc, is a Binary star approximately 41 Light-years pi1 Ursae Majoris is a yellow G-type main sequence dwarf with a mean Apparent magnitude of +5 5Vb 46. 5  ?
HD 139664[15] F5IV-V 57 60–109
Eta Corvi[16] F2V 59 100–150
HD 53143[15] K1V 60  ?
Beta Pictoris[11] A5V 63 25–550
Zeta Leporis[17] A2Vann 70 2–8
HD 92945[18] K1V 72 45–175
HD 107146[19] G2V 88 130
Fomalhaut[5] A3V 133 25
HD 12039[20] G3-5V 137 5
HD 15115[21] F2V 150 315–550
HR 4796 A[22][23] A0V 220 200
HD 141569[23] B9. Eta Corvi (&eta Crv / &eta Corvi is a yellow-white Main sequence star in the Constellation Corvus. HD 53143 is an orange Main sequence Star that is located about 60 Light years from the Sun. Beta Pictoris (β Pic / β Pictoris is the second brightest Star in the Constellation Pictor. Zeta Leporis (ζ Lep / ζ Leporis White main sequence star approximately 70 Light-years away in the Constellation of Lepus. HD 107146 is a G2V ( Yellow dwarf) Star, located 88 Light years from Earth. Fomalhaut (α PsA / α Piscis Austrini / Alpha Piscis Austrini is the brightest star in the Constellation Piscis Austrinus and one of the brightest HD 12039 is a Variable star in the Constellation of Cetus. It is categorized as a BY Draconis variable, and has a Stellar classification HD 15115 is a yellow-white star The asymmetric disk encircling the star was discovered using the Hubble Space Telescope and further investigated by the W 5e 320 400
HD 113766 A[24] F4V 430 0. HD 113766 is a Binary star system located 424 ly from Earth in the direction of the Constellation Centaurus. 35–5. 8

The orbital distance of the belt is an estimated mean distance or range, based either on direct measurement from imaging or derived from the temperature of the belt. The Earth has an average distance from the Sun of 1 AU. EARTH was a short-lived Japanese vocal trio which released 6 singles and 1 album between 2000 and 2001

See also

References

  1. ^ Z. An accretion disc (or accretion disk) is a structure (often a Circumstellar disk) formed by diffuse material in orbital motion around a central body The asteroid belt is the region of the Solar System located roughly between the orbits of the Planets Mars and Jupiter. The Kuiper belt (ˈkaɪpɚ to rhyme with "viper" sometimes called the Edgeworth-Kuiper belt, is a region of the Solar System beyond the planets extending A protoplanetary disk (or proplyd) is a rotating Circumstellar disk of dense gas surrounding a young newly formed star a T Tauri star or Herbig star Wang, D. Chakrabarty, D. L. Kaplan (2006). "A debris disk around an isolated young neutron star". Nature 440 (7085): 772–775. doi:10.1038/nature04669. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  2. ^ "Spitzer Team Says Debris Disk Could Be Forming Infant Terrestrial Planets", NASA, December 14, 2005. Retrieved on 2007-01-03. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1431 - Joan of Arc is handed over to the Bishop Pierre Cauchon.  
  3. ^ "Spitzer Sees Dusty Aftermath of Pluto-Sized Collision", NASA, January 10, 2005. Retrieved on 2007-01-03. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1431 - Joan of Arc is handed over to the Bishop Pierre Cauchon.  
  4. ^ Debris Disk Database. Royal Observatory Edinburgh. Retrieved on 2007-01-03. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1431 - Joan of Arc is handed over to the Bishop Pierre Cauchon.
  5. ^ a b c Joint Astronomy Centre (April 21, 1998). "Astronomers discover possible new Solar Systems in formation around the nearby stars Vega and Fomalhaut". Press release. A news release, media release, press release or press statement is a written or recorded Communication directed at members of the News Retrieved on 2006-04-24. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1479 BC - Thutmose III ascends to the throne of Egypt, although power effectively shifts to Hatshepsut (according to
  6. ^ a b "University Of Arizona Scientists Are First To Discover Debris Disk Around Star Orbited By Planet", ScienceDaily, October 23, 1998. Retrieved on 2006-05-24. Year 2006 ( MMVI) was a Common year starting on Sunday of the Gregorian calendar. Events 1218 - The Fifth Crusade leaves Acre for Egypt. 1276 - Magnus Ladulås is crowned  
  7. ^ a b J. S. Greaves; W. S. Holland; M. C. Wyatt; W. R. F. Dent; E. I. Robson; I. M. Coulson; T. Jenness; G. H. Moriarty-Schieven; G. R. Davis; H. M. Butner; W. K. Gear; C. Dominik; H. J. Walker (2005). "Structure in the Epsilon Eridani Debris Disk" ( – Scholar search). The Astrophysical Journal 619: L187 – L190. doi:10.1086/428348. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  8. ^ a b Scott Kenyon & Benjamin Bromley (2007). Stellar Flybys & Planetary Debris Disks. Smithsonian Astrophysical Observatory. Retrieved on 2007-07-23. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1632 - Three hundred colonists bound for New France depart from Dieppe France.
  9. ^ SIMBAD: Query by identifiers. Centre de Données astronomiques de Strasbourg. Retrieved on 2007-07-17. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 180 - Twelve inhabitants of Scillium in North Africa are executed for being Christians
  10. ^ J. S. Greaves, M. C. Wyatt, W. S. Holland, W. R. F. Dent (2004). "The debris disc around tau Ceti: a massive analogue to the Kuiper Belt". Monthly Notices of the Royal Astronomical Society 351 (3): L54–L58. doi:10.1111/j.1365-2966.2004.07957.x. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  11. ^ a b Backman, D. E. (1996). "Dust in beta PIC / VEGA Main Sequence Systems". Bulletin of the American Astronomical Society 28: 1056.  
  12. ^ Sanders, Robert. "Dust around nearby star like powder snow", UC Berkeley News, January 8, 2007. Retrieved on 2007-01-11. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1055 - Theodora is crowned Empress of the Byzantine Empire.  
  13. ^ Lisse, C. M. ; Beichman, C. A. ; Bryden, G. ; Wyatt, M. C. (1999). "On the Nature of the Dust in the Debris Disk around HD 69830". The Astrophysical Journal 658 (1): 584–592. doi:10.1086/511001. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  14. ^ Beichman, C. A. ; Tanner, A. ; Bryden, G. ; Stapelfeldt, K. R. ; Werner, M. W. ; Rieke, G. H. ; Trilling, D. E. ; Lawler, S. ; Gautier, T. N. (2006). "IRS Spectra of Solar-Type Stars: A Search for Asteroid Belt Analogs". The Astrophysical Journal 639: 1166–1176. doi:10.1086/499424. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  15. ^ a b Kalas, Paul; Graham, James R. ; Clampin, Mark C. ; Fitzgerald, Michael P. (2006). "First Scattered Light Images of Debris Disks around HD 53143 and HD 139664". The Astrophysical Journal 637 (1): L57–L60. doi:10.1086/500305. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  16. ^ Wyatt, M. C. ; Greaves, J. S. ; Dent, W. R. F. ; Coulson, I. M. (2005). "Submillimeter Images of a Dusty Kuiper Belt around Corvi" ( – Scholar search). The Astrophysical Journal 620: 492–500. doi:10.1086/426929. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  17. ^ M. M. Moerchen, C. M. Telesco, C. Packham, T. J. J. Kehoe (2006). "Mid-infrared resolution of a 3 AU-radius debris disk around Zeta Leporis". Astrophysical Journal Letters.  
  18. ^ D. Golimowski et al (2007). Observations and Models of the Debris Disk around K Dwarf HD 92945. University of California, Berkeley Astronomy Department. Retrieved on 2007-07-17. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 180 - Twelve inhabitants of Scillium in North Africa are executed for being Christians
  19. ^ Jonathan P. Williams et al (2004). "Detection of cool dust around the G2V star HD 107146". Astrophysical Journal 604: 414–419. doi:10.1086/381721. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  20. ^ Hines, Dean C. et al (2006). "The Formation and Evolution of Planetary Systems (FEPS): Discovery of an Unusual Debris System Associated with HD 12039". The Astrophysical Journal 638 (2): 1070–1079. doi:10.1086/498929. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  21. ^ Kalas, Paul; Fitzgerald, Michael P. ; Graham, James R. (2007). "Discovery of Extreme Asymmetry in the Debris Disk Surrounding HD 15115". The Astrophysical Journal 661 (1): L85–L88. doi:10.1086/518652. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  22. ^ Koerner, D. W. ; Ressler, M. E. ; Werner, M. W. ; Backman, D. E. (1998). "Mid-Infrared Imaging of a Circumstellar Disk around HR 4796: Mapping the Debris of Planetary Formation". Astrophysical Journal Letters 503: L83. doi:10.1086/311525. A digital object identifier ( DOI) is a permanent identifier given to an Electronic document.  
  23. ^ a b Villard, Ray; Weinberger, Alycia; Smith, Brad (January 8, 1999). Hubble Views of Dust Disks and Rings Surrounding Young Stars Yield Clues. HubbleSite. Retrieved on 2007-06-17. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 1462 - Vlad III the Impaler attempts to assassinate Mehmed II ( The Night Attack) forcing him to retreat
  24. ^ Meyer, M. R. ; Backman, D. . "Belt of Material Around Star May Be First Step in Terrestrial Planet Formation", University of Arizona, NASA, January 08, 2002. Retrieved on 2007-07-17. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 180 - Twelve inhabitants of Scillium in North Africa are executed for being Christians  

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