XO-1b
XO-1b is an extrasolar planet approximately 536 light-years away from Earth.
Size comparison of XO-1b with Jupiter. | |
| Discovery | |
|---|---|
| Discovered by | Peter R. McCullough et al. |
| Discovery site | Haleakala Observatory, Hawaii |
| Discovery date | 18 May 2006 |
| Transit and Radial velocity | |
| Orbital characteristics | |
| 0.04930+0.00091 −0.00096 AU | |
| Eccentricity | <0.019 |
| 3.94150685±0.00000091 d | |
| Inclination | 88.8 ± 0.2 |
| Semi-amplitude | 116 ± 9 |
| Star | XO-1 |
| Physical characteristics | |
Mean radius | 1.21 ± 0.03 RJ |
| Mass | 0.913±0.038 MJ |
Mean density | 0.64 ± 0.05 g/cm3 (0.0231 ± 0.0018 lb/cu in) |
| 15.8 ± 1.5 m/s2 (51.8 ± 4.9 ft/s2) | |
The planet XO-1b is named Negoiu. The name was selected in the NameExoWorlds campaign by Romania, during the 100th anniversary of the IAU. Negoiu is the second highest peak in Romania.
In 2006, the XO Project, an international team of professional and amateur astronomers, discovered a Jupiter-sized planet, later named XO-1b, orbiting a Sun-like star. The team, led by Peter R. McCullough of the Space Telescope Science Institute in Baltimore, had four amateur astronomers hailing from North America and Europe. An independent confirmation of the planet was made by the Wide Angle Search for Planets project later that same year.
The XO Project team employed the relatively inexpensive XO Telescope, made from commercial equipment, to search for extrasolar planets. This telescope is on the Hawaiian Island of Maui.
From September 2003 to September 2005, the XO Telescope detected tens of thousands of bright stars. In that time, McCullough's team of amateur astronomers studied a few dozen stars they had previously identified as promising candidates for extrasolar planets. The star XO-1, in particular, was marked as a promising candidate in June 2005. The amateur astronomers observed it from June to July 2005, eventually confirming that a planet-sized object was eclipsing it. McCullough's team then turned to the McDonald Observatory in Texas for information on the object's mass and to confirm it was a planet.