 Size comparison of XO-2 b (gray) with Jupiter. | |
| Discovery | |
|---|---|
| Discovered by | Burke et al. |
| Discovery date | 2007 |
| Transit (including secondary eclipse) | |
| Orbital characteristics | |
| 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] |
| 2454147.74902 ± 0.00002 | |
| ? | |
| Semi-amplitude | 80.2 |
| Star | XO-2N (XO-2B) |
| Physical characteristics | |
| 0.973 ± 0.03RJ | |
| Mass | 0.57 ± 0.06MJ |
Meandensity | 0.82 g/cm3[citation needed] |
| 1.42 m/s2 (0.145 g0)[citation needed] | |
| Temperature | 1,208 K (935 °C) |
XO-2Nb (or rarely XO-2Bb) is anextrasolar planet orbiting thestarXO-2N, the fainter component of XO-2 wide binary star in theconstellationLynx.[2] This planet was found by thetransit method in 2007 by Burke et al. This was the second such planet found by theXO telescope.
Like most planets found by the transit method, it is a roughlyJupiter sized planet that orbits very close to its host star; in this case, it has a surfacetemperature of about 1200K, so it belongs to a group of exoplanets known ashot 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'satmosphere. The large radius for its mass gives a low density of 820 kg/m3.[3]
Media related toXO-2b at Wikimedia Commons
