 An artist's impression of MOA-2007-BLG-192Lb orbiting its primary. | |
| Discovery | |
|---|---|
| Discovered by | Bennett et al. |
| Discovery site | Mount John University Observatory,  New Zealand |
| Discovery date | 30 May 2008 |
| Detection method | Gravitational microlensing |
| Orbital characteristics | |
| Semi-major axis | 2.02±0.44 AU |
| Star | MOA-2007-BLG-192L |
| Physical characteristics | |
| Mass | 12.49+65.47 −8.03 ME (likely between 3 and 12 ME) |
MOA-2007-BLG-192Lb, occasionally shortened to MOA-192 b, is an extrasolar planet approximately 7,000 light-years away in the constellation of Sagittarius. The planet was discovered orbiting the low-mass star MOA-2007-BLG-192L. It was found when it caused a gravitational microlensing event on May 24, 2007, which was detected as part of the MOA-II microlensing survey at the Mount John University Observatory in New Zealand.
The mass of the planet is not well-known. It is anything between 2.75 and 105 Earth masses (ME), although it is more likely to be between 3 and 12 ME. The mass range also means that the planet's classification varies, from a Super-Earth to a Sub-Saturn. It is located at 2.02 astronomical units from its host star.
Host star
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Sagittarius |
| Right ascension | 18 18 03.8 |
| Declination | −27° 09′ 00.27″ |
| Characteristics | |
| Evolutionary stage | Red dwarf |
| Spectral type | M |
| Astrometry | |
| Distance | 7040±980 ly (2160±300 pc) |
| Details | |
| Mass | 0.28±0.04 M☉ |
| Database references | |
| SIMBAD | data |
MOA-2007-BLG-192L is a red dwarf star, one of the smallest and least massive type of stars, as well as one of the most numerous in the Milky Way. It was initially estimated to have a mass 6% the mass of the Sun, which would probably be too low to sustain nuclear fusion at its core, making it a dimly glowing brown dwarf. However, this mass was based on an erroneous parallax, and a further analysis suggest a higher mass of 0.24 M☉. This would make it a red dwarf.
Both MOA-2007-BLG-192L and its planet are located at a distance of 2,160 pc (7,000 ly) from Earth, in the direction of the constellation Sagittarius.
Notes
- ^ Obtained with a right ascension of 18 18 03.8 and a declination of −27° 09′ 00.27″ on this website.
References
- ^ Terry, Sean K.; Beaulieu, Jean-Philippe; Bennett, David P.; Hamdorf, Euan; Bhattacharya, Aparna; Chaudhry, Viveka; Cole, Andrew A.; Koshimoto, Naoki; Anderson, Jay; Bachelet, Etienne; Blackman, Joshua W.; Bond, Ian A.; Lu, Jessica R.; Marquette, Jean Baptiste; Ranc, Clément (2024-07-15). "Unveiling MOA-2007-BLG-192: An M Dwarf Hosting a Likely Super-Earth". The Astronomical Journal. 168 (2): 72. arXiv:2403.12118. doi:10.3847/1538-3881/ad5444. ISSN 1538-3881.
- Planet Quest: New Worlds Atlas Archived 2008-07-01 at the Wayback Machine, JPL. Accessed on line July 2, 2008.
- Bennett, D. P.; Bond, I. A.; Udalski, A.; et al. (2008). "A Low-Mass Planet with a Possible Sub-Stellar-Mass Host in Microlensing Event MOA-2007-BLG-192". The Astrophysical Journal. 684 (1): 663–683. arXiv:0806.0025. Bibcode:2008ApJ...684..663B. doi:10.1086/589940. S2CID 14467194.
- "Red dwarf star | Definition, Facts, & Temperature | Britannica". Britannica. Retrieved 2024-07-23.
- Smallest Extrasolar Planet Portends Other Earths Archived 2009-02-28 at the Wayback Machine, Richard A. Kerr, ScienceNOW Daily News, June 2, 2008. Accessed on line June 16, 2008.
External links
- "MOA-2007-BLG-192Lb: A Low-Mass Planet with a Possible Sub-Stellar-Mass Host". Archived from the original on 2008-06-06. Retrieved 2008-06-28.
