Astronomy:OTS 44

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Short description: Celestial object in the constellation Chamaeleon
OTS 44
Brown dwarf OTS 44 with disc.jpg
An artist's concept of OTS 44's dust disk
Observation data
Equinox J2000.0]] (ICRS)
Constellation Chamaeleon
Right ascension  11h 10m 11.5s
Declination −76° 32′ 13″
Characteristics
Spectral type M9.5[1]
Astrometry
Distance554 ly
(170 pc)
Details
Mass0.011[2] M
Radius0.23[1]–0.57[3] R
Luminosity0.0013[1]–0.0024[3] L
Temperature1,700[2][3]–2,300[1] K
Database references
SIMBADdata

OTS 44 is a free-floating planetary-mass object or brown dwarf located at 550 light-years (170 pc) in the constellation Chamaeleon near the reflection nebula IC 2631. It is among the lowest-mass free-floating substellar objects, with approximately 11.5 times the mass of Jupiter, or approximately 1.1% that of the Sun.[2][4] Its radius is not very well known and is estimated to be 23–57% that of the Sun.[1][3]

OTS 44 was discovered in 1998 by Oasa, Tamura, and Sugitani as a member of the star-forming region Chamaeleon I.[5][6] Based upon infrared observations with the Spitzer Space Telescope and the Herschel Space Observatory, OTS 44 emits an excess of infrared radiation for an object of its type, suggesting it has a circumstellar disk of dust and particles of rock and ice.[1][3][7] This disk has a mass of at least 10 Earth masses.[3][contradictory] Observations with the SINFONI spectrograph at the Very Large Telescope show that the disk is accreting matter at the rate of approximately 10−11 of the mass of the Sun per year.[3] It could eventually develop into a planetary system. Observations with ALMA detected the disk in millimeter wavelengths. The observations constrained the dust mass of the disk between 0.07 and 0.63 M, but these mass estimates are limited by assumptions on poorly constrained parameters.[8]

See also

  • SCR 1845-6357, a binary system comprising a red dwarf and a brown dwarf
  • Cha 110913-773444, an astronomical object that may be a free-floating planet surrounded by what appears to be a protoplanetary disk

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Luhman, K. L. et al. (February 2005), "Spitzer Identification of the Least Massive Known Brown Dwarf with a Circumstellar Disk", The Astrophysical Journal 620 (1): L51–L54, doi:10.1086/428613, Bibcode2005ApJ...620L..51L 
  2. 2.0 2.1 2.2 Bonnefoy, M.; Chauvin, G.; Lagrange, A.-M.; Rojo, P.; Allard, F.; Pinte, C.; Dumas, C.; Homeier, D. (2014). "A library of near-infrared integral field spectra of young M-L dwarfs". Astronomy & Astrophysics 562 (127): A127. doi:10.1051/0004-6361/201118270. Bibcode2014A&A...562A.127B. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Joergens, V.; Bonnefoy, M.; Liu, Y.; Bayo, A.; Wolf, S.; Chauvin, G.; Rojo, P. (2013). "OTS 44: Disk and accretion at the planetary border". Astronomy & Astrophysics 558 (7): L7. doi:10.1051/0004-6361/201322432. Bibcode2013A&A...558L...7J. 
  4. Luhmann, K. L.; Peterson, D. E.; Megeath, S. T. (2004). "Spectroscopic Confirmation of the Least Massive Known Brown Dwarf in Chamaeleon". The Astrophysical Journal 617 (1): 565–568. doi:10.1086/425228. Bibcode2004ApJ...617..565L. 
  5. Tamura, M.; Itoh, Y.; Oasa, Y.; Nakajima, T. (1998). "Isolated and Companion Young Brown Dwarfs in the Taurus and Chamaeleon Molecular Clouds". Science 282 (5391): 1095–7. doi:10.1126/science.282.5391.1095. PMID 9804541. Bibcode1998Sci...282.1095T. 
  6. Oasa, Y.; Tamura, M.; Sugitani, K. (1999). "A Deep Near-Infrared Survey of the Chamaeleon I Dark Cloud Core". The Astrophysical Journal 526 (1): 336–343. doi:10.1086/307964. Bibcode1999ApJ...526..336O. 
  7. "Blurring the lines between stars and planets: Lonely planets offer clues to star formation". http://www.mpia.de/Public/menu_q2e.php?Aktuelles/PR/2013/PR_2013_09/PR_2013_09_en.html. 
  8. Bayo, Amelia; Joergens, Viki; Liu, Yao; Brauer, Robert; Olofsson, Johan; Arancibia, Javier; Pinilla, Paola; Wolf, Sebastian et al. (May 2017). "First Millimeter Detection of the Disk around a Young, Isolated, Planetary-mass Object" (in en). Astrophysical Journal Letters 841 (1): L11. doi:10.3847/2041-8213/aa7046. ISSN 0004-637X. Bibcode2017ApJ...841L..11B. 

External links