Global Information2M1207b information
 Size comparison of 2M1207b with Jupiter. | |
| Discovery | |
|---|---|
| Discovered by | Chauvin et al. |
| Discovery site | Paranal Observatory, Chile |
| Discovery date | April 2004 |
Detection method | Imaged |
| Orbital characteristics | |
Semi-major axis | 24–231 AU (3.6×109–3.46×1010 km)[1] |
| Eccentricity | 0.02–0.98[1] |
Orbital period (sidereal) | 633–20046[1] y |
| Inclination | 13–150[1] |
Longitude of ascending node | 7–174[1] |
Time of periastron | 2107.69–12883.36[1] |
Argument of periastron | 4–176[1] |
| Star | 2M1207 |
| Physical characteristics | |
Mean radius | 1.15 RJ[2] |
| Mass | 5.5±0.5[3] MJ |
| Temperature | 1200 K[3] |
Spectral type | mid-to-late L[3] |
| Atmosphere | |
| Composition by volume | hydrogen, water, carbon monoxide, helium[3][4] |
2M1207b is a planetary-mass object orbiting the brown dwarf 2M1207, in the constellation Centaurus, approximately 170 light-years from Earth.[5] It is one of the first candidate exoplanets to be directly observed (by infrared imaging). It was discovered in April 2004 by the Very Large Telescope (VLT) at the Paranal Observatory in Chile by a team from the European Southern Observatory led by Gaël Chauvin.[6] It is believed to be from 5 to 6 times the mass of Jupiter[3] and may orbit 2M1207 at a distance roughly as far from the brown dwarf as Pluto is from the Sun.[7]
The object is a very hot gas giant; the estimated surface temperature is roughly 1200 K (930 °C or 1700 °F),[3] mostly due to gravitational contraction.[8] Its mass is well below the calculated limit for deuterium fusion in brown dwarfs, which is 13 Jupiter masses. The projected distance between 2M1207b and its primary is around 40 AU (similar to the mean distance between Pluto and the Sun).[9] Its infrared spectrum indicates the presence of water molecules in its atmosphere.[10][4] The object is not a likely candidate to support life, either on its surface or on any satellites.
- ^ a b c d e f g Cite error: The named reference
Blunt2017was invoked but never defined (see the help page). - ^ "The Extrasolar Planet Encyclopaedia — 2M1207 A". Extrasolar Planets Encyclopaedia. Paris Observatory. Retrieved 2024-03-24.
- ^ a b c d e f Cite error: The named reference
Luhman et al 2023was invoked but never defined (see the help page). - ^ a b Barman, Travis S.; Macintosh, Bruce; Konopacky, Quinn M.; Marois, Christian (2011-07-01). "The Young Planet-mass Object 2M1207b: A Cool, Cloudy, and Methane-poor Atmosphere". The Astrophysical Journal. 735 (2): L39. arXiv:1106.1201. Bibcode:2011ApJ...735L..39B. doi:10.1088/2041-8205/735/2/L39. ISSN 0004-637X. S2CID 44225360.
- ^ Mamajek, Eric (November 8, 2007). "The Distance to the 2M1207 System". Archived from the original on 2008-01-24. Retrieved June 15, 2008.
- ^ Chauvin, G.; Lagrange, A.-M.; Dumas, C.; Zuckerman, B.; Mouillet, D.; Song, I.; Beuzit, J.-L.; Lowrance, P. (2004). "A giant planet candidate near a young brown dwarf: Direct VLT/NACO observations using IR wavefront sensing". Astronomy & Astrophysics. 425 (2): L29–L32. arXiv:astro-ph/0409323. Bibcode:2004A&A...425L..29C. doi:10.1051/0004-6361:200400056. ISSN 0004-6361.
- ^ "Star: 2M1207". Extrasolar Planets Encyclopaedia. Archived from the original on 2011-10-06. Retrieved June 15, 2008.
- ^ Mohanty, Subhanjoy; Jayawardhana, Ray; Huelamo, Nuria; Mamajek, Eric (2007-03-10). "The Planetary Mass Companion 2MASS 1207−3932B: Temperature, Mass, and Evidence for an Edge-on Disk". The Astrophysical Journal. 657 (2): 1064–1091. arXiv:astro-ph/0610550. Bibcode:2007ApJ...657.1064M. doi:10.1086/510877. ISSN 0004-637X.
- ^ Estimated observed projected separation from observed angular separation and estimated distance.
- ^ Cite error: The named reference
esoprwas invoked but never defined (see the help page).