) Size comparison of XO-2 b (gray) with Jupiter. | |
| Discovery | |
|---|---|
| Discovered by | Burke et al. |
| Discovery date | 2007 |
Detection method | Transit (including secondary eclipse) |
| Orbital characteristics | |
Semi-major axis | 0.0369 ± 0.002 AU (5,520,000 ± 300,000 km) |
| Eccentricity | 0 |
| 2.61586178 ± 0.00000075[1] d | |
| Inclination | 87.62 ± 0.51[1] |
Time of periastron | 2454147.74902 ± 0.00002 |
Argument of periastron | ? |
| Semi-amplitude | 80.2 |
| Star | XO-2N (XO-2B) |
| Physical characteristics | |
Mean radius | 0.973 ± 0.03 RJ |
| Mass | 0.57 ± 0.06 MJ |
Mean density | 820 kg/m3 (1,380 lb/cu yd) |
| 1.42 m/s2 (4.7 ft/s2) | |
| Temperature | 1208 |
XO-2Nb (or rarely XO-2Bb) is an extrasolar planet orbiting the star XO-2N, the fainter component of XO-2 wide binary star in the constellation Lynx.[2] This planet was found by the transit method in 2007 by Burke et al. This was the second such planet found by the XO telescope.
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Like most planets found by the transit method, it is a roughly Jupiter sized planet that orbits very close to its host star; in this case, it has a surface temperature of about 1200 K, so it belongs to a group of exoplanets known as hot Jupiters. The planet takes 2.6 days to orbit the star at the average distance of 0.0369 AU. The planet has mass of 57% of Jupiter and radius of 97% of Jupiter. The radius is relatively large for its mass, probably due to its intense heating from its nearby star that bloats the planet's atmosphere. The large radius for its mass gives a low density of 820 kg/m3.[3]
See also
References
- ^ a b Sing, D. K.; et al. (2011). "Gran Telescopio Canarias OSIRIS transiting exoplanet atmospheric survey: detection of potassium in XO-2b from narrowband spectrophotometry". Astronomy and Astrophysics. 527. article number A73. arXiv:1008.4795. Bibcode:2011A&A...527A..73S. doi:10.1051/0004-6361/201015579.
- ^ "XO-2b". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2009-04-26.
- ^ Burke, Christopher J.; et al. (2007). "XO-2b: Transiting Hot Jupiter in a Metal-rich Common Proper Motion Binary". The Astrophysical Journal. 671 (2): 2115–2128. arXiv:0705.0003. Bibcode:2007ApJ...671.2115B. doi:10.1086/523087.
External links
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Media related to XO-2b at Wikimedia Commons