OTS 44
OTS 44 (orange crosshair) and surrounding nebulae | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Chamaeleon |
| Right ascension | 11h 10m 11.5s |
| Declination | −76° 32′ 13″ |
| Characteristics | |
| Spectral type | M9.5[1] |
| Astrometry | |
| Distance | 530 ly (162.5 pc)[2] |
| Details | |
| Mass | 6–17 MJ, average 11.5[2] MJup |
| Radius | 3.2 or 3.6[3] RJup |
| Luminosity | 0.00126±0.00023[a][3] – 0.0024[2] L☉ |
| Temperature | 1,700[3][2]–2,300[1] K |
| Age | 1–6[3] Myr |
| Database references | |
| SIMBAD | data |
OTS 44 is a young, free-floating planetary-mass brown dwarf or rogue planet, located 530 light-years (160 pc) away in the star-forming molecular cloud Chamaeleon I in the constellation Chamaeleon. It is surrounded by a protoplanetary disk of gas and dust, from which it is actively accreting mass at an approximate rate of 500 billion kilograms per second (or equivalently, 7.6×10−12 solar masses per year).[2] With an estimated age between 1 and 6 million years, OTS 44 has not existed long enough to cool down, so it glows red with a temperature of around 1,700 K (1,430 °C; 2,600 °F) and a stellar spectral type of M9.5.[3]
Size and form
OTS 44 is estimated to be 6–17 times more massive than Jupiter,[4] though it is more likely below 13 Jupiter masses—in the planetary mass range, where it cannot fuse deuterium unlike brown dwarfs.[3] OTS 44 likely has a radius of 3.2 or 3.6 Jupiter radii, but surrounding dust from OTS 44's protoplanetary disk makes this estimate uncertain.[3]: 16, 19 The disk of OTS 44 is estimated to span at least several astronomical units in radius with a flared shape—decreasing in density but increasing in vertical thickness at farther distances from the object.[2]: 2–3 OTS 44's disk contains a total estimated mass of approximately 0.1 Jupiter masses or 30 Earth masses,[2] with a small fraction of this mass constituting dust in the disk.[4] OTS 44's disk will eventually coalesce to form a planetary system, with enough mass to potentially create one small gas giant planet and several Earth-sized rocky planets.[5][6]
Description
OTS 44 was discovered as a brown dwarf candidate in 1998 by Japanese astronomers Yumiko Oasa, Motohide Tamura, and Koji Sugitani, whose surnames form the acronym "OTS" in the object's name. It a member of the star-forming molecular cloud Chamaeleon I.[7][8] It was spectroscopically confirmed as a brown dwarf in 2004.[9] 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][2][10] This disk (gas+dust) has a spectral energy distribution (SED)-fitted mass of at about 30 Earth masses.[2] 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.[2] It could eventually develop into a planetary system.[10] 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.[4] Another work estimates the dust mass to 0.064 M🜨 (5.2 M☾) for dust particles of 1 mm in size and 0.295 M🜨 (24 M☾) for dust particles of 1 μm in size.[11]
See also
Other free-floating rogue planets and brown dwarfs with protoplanetary disks:
- Cha 110913-773444, rogue planet or brown dwarf surrounded by what appears to be a dusty disk
- Cha 1107−7626, a young rogue planet that underwent an episode of rapid accretion of material from its disk
- 2MASS J11151597+1937266, a young rogue planet or brown dwarf actively accreting material from its disk
- KPNO-Tau 12, another young rogue planet or brown dwarf that is actively accreting material from its disk
- J1407b, a possible disked object thought to have transited the star V1400 Centauri
Notes
- ^ In Table of 8 of Bonnefoy et al. (2014), OTS 44's effective luminosity is given as a base 10 logarithm: −2.90±0.08. The luminosity of 0.00126±0.00023 L☉ can be obtained by taking 10 to the power of the aforementioned logarithm value; the uncertainty is calculated via propagation of error.
References
- ^ a b c 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, arXiv:astro-ph/0502100, Bibcode:2005ApJ...620L..51L, doi:10.1086/428613, S2CID 15340083
- ^ a b c d e f g h i j Joergens, V.; Bonnefoy, M.; Liu, Y.; Bayo, A.; Wolf, S.; Chauvin, G.; Rojo, P. (2013-10-01). "OTS 44: Disk and accretion at the planetary border". Astronomy and Astrophysics. 558: L7. arXiv:1310.1936. Bibcode:2013A&A...558L...7J. doi:10.1051/0004-6361/201322432. ISSN 0004-6361.
- ^ a b c d e f g 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. arXiv:1306.3709. Bibcode:2014A&A...562A.127B. doi:10.1051/0004-6361/201118270. S2CID 53064211.
- ^ a b c Bayo, Amelia; Joergens, Viki; Liu, Yao; Brauer, Robert; Olofsson, Johan; Arancibia, Javier; Pinilla, Paola; Wolf, Sebastian; Ruge, Jan Philipp; Henning, Thomas; Natta, Antonella (May 2017). "First Millimeter Detection of the Disk around a Young, Isolated, Planetary-mass Object". Astrophysical Journal Letters. 841 (1): L11. arXiv:1705.06378. Bibcode:2017ApJ...841L..11B. doi:10.3847/2041-8213/aa7046. hdl:10150/624481. ISSN 0004-637X. S2CID 73605838.
- ^ "Tiny Brown Dwarf's Disk May Form Miniature Solar System". Center for Astrophysics. Harvard University. 2005-02-07. Retrieved 2025-12-07.
- ^ "Astronomers Discover Beginnings of 'Mini' Solar System". Spitzer Space Telescope. Jet Propulsion Laboratory. 2005-02-07. Retrieved 2025-12-07.
- ^ 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. Bibcode:1998Sci...282.1095T. doi:10.1126/science.282.5391.1095. PMID 9804541.
- ^ 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. Bibcode:1999ApJ...526..336O. doi:10.1086/307964.
- ^ 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. arXiv:astro-ph/0411445. Bibcode:2004ApJ...617..565L. doi:10.1086/425228. S2CID 18157277.
- ^ a b "Blurring the lines between stars and planets: Lonely planets offer clues to star formation". MPIA Science Release 2013-09. Retrieved 1 September 2014.
- ^ Wu, Ya-Lin; Bowler, Brendan P.; Sheehan, Patrick D.; Close, Laird M.; Eisner, Joshua A.; Best, William M. J.; Ward-Duong, Kimberly; Zhu, Zhaohuan; Kraus, Adam L. (2022-05-01). "ALMA Discovery of a Disk around the Planetary-mass Companion SR 12 c". The Astrophysical Journal. 930 (1): L3. arXiv:2204.06013. Bibcode:2022ApJ...930L...3W. doi:10.3847/2041-8213/ac6420. ISSN 0004-637X.