XO Project
The XO Project is an international team of amateur and professional astronomers tasked with identifying extrasolar planets. They are led by Peter R. McCullough of the Space Telescope Science Institute.[1] It is primarily funded by NASA's Origins Program and the Director's Discretionary Fund of the Space Telescope Science Institute.[2][3]
Duties
Preliminary identification of possible star candidates starts at the Haleakala telescope in Hawaii by a team of professional astronomers. Once they identify a star that dims slightly from time to time (the transit method), the information is forwarded to a team of amateur astronomers who then investigate for additional evidence suggesting this dimming is caused by a transiting planet. Once enough data is collected, it is forwarded to the University of Texas McDonald Observatory to confirm the presence of a transiting planet by a second team of professional astronomers.[2]
Equipment
McCullough and his team employed a relatively inexpensive telescope called the XO Telescope, made from commercial equipment, to search for extrasolar planets. The construction of the one-of-a-kind telescope cost $60,000 for the hardware, and much more than that for the associated software.[4] The telescope consists of two 200-millimeter telephoto camera lenses, and resembles binoculars in shape. It is similar to the TrES survey telescope. It stands on the summit of the Haleakalā volcano and 3,054 m (10,000 foot) in Hawaii.[1] Their first discovery of a Jupiter-sized planet orbiting a Sun-like star 600 light-years from Earth in the constellation Corona Borealis—XO-1b—was reported May 16, 2006 on Newswise.
In 2016 three similar double telescopes were operating, two in Spain and one in Utah.[5]
Discoveries
The XO telescope has discovered six objects so far, five are hot Jupiter planets and one, XO-3b, may be a brown dwarf.
Star | Constellation | Right ascension |
Declination | App. mag. |
Distance (ly) | Spectral type |
Planet | Mass (MJ) |
Radius (RJ) |
Orbital period (d) |
Semimajor axis (AU) |
Orbital eccentricity |
Inclination (°) |
Discovery year |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
XO-1[6] | Corona Borealis | 16h 02m 12s | +28° 10′ 11″ | 11.319 | 600 | G1V | XO-1b | 0.9 | 1.3 | 3.941534 | 0.0488 | 0 | 87.7 | 2006 |
XO-2N[7] | Lynx | 07h 48m 07s | +50° 13′ 33″ | 11.25 | 486 | K0V | XO-2Nb | 0.57 | 0.973 | 2.615838 | 0.0369 | 0 | 88.58 | 2007 |
XO-3[8] | Camelopardalis | 04h 21m 53s | +57° 49′ 01″ | 9.91 | 850 | F5V | XO-3b | 11.79 | 1.217 | 3.1915239 | 0.0454 | 0.26 | 84.2 | 2007 |
XO-4[9] | Lynx | 07h 21m 33.1657s | +58° 16′ 05.005″ | 10.78 | 956 | F5V | XO-4b | 1.72 | 1.34 | 4.12502 | 0.0555 | 0.0024 | 88.7 | 2008 |
XO-5[10] | Lynx | 07h 46m 51.959s | +39° 05′ 40.47″ | 12.1 | 881 | G8V | XO-5b | 1.15 | 1.15 | 4.187732 | 0.0508 | 0.0029 | 86.8 | 2008 |
XO-6[11] | Camelopardalis | 6h 19m 10.31s | +73° 49′ 39.24″ | 10.28 | 760 | F5V | XO-6b | 4.4 | 2.07 | 3.76 | 0.082 | 0 | 86.0 | 2016 |
XO-7 | Draco | 18h 29m 52.30s | 85° 13′ 59.58″ | 10.52 | 763 | G0V | XO-7b | 0.71 | 1.373 | 2.8641424 | 0.04421 | 0.038 | 83.45 | 2019 |
See also
A subset of XO light curves are available at the NASA Exoplanet Archive.
Other Ground-Based Transit Surveys
- Next-Generation Transit Survey
- Trans-Atlantic Exoplanet Survey or TrES
- HATNet Project or HAT
- Kilodegree Extremely Little Telescope or KELT
- SuperWASP or WASP
References
- Astronomers Catch Planet By Unusual Means, Space Daily
- XO-3b: Supersized planet or oasis in the 'brown dwarf desert'?, EurekAlert!
- Astronomers Use Innovative Technique to Find Extrasolar Planet, HubbleSite
- McCullough, P. R.; et al. (2005). "The XO Project: Searching for Transiting Extrasolar Planet Candidates". Publications of the Astronomical Society of the Pacific. 117 (834): 783–795. arXiv:astro-ph/0505560. Bibcode:2005PASP..117..783M. doi:10.1086/432024. S2CID 16972795.
- Crouzet, N.; McCullough, P. R.; Long, D.; Rodriguez, P. Montanes; Etangs, A. Lecavelier des; Ribas, I.; Bourrier, V.; Hébrard, G.; Vilardell, F. (February 2017). "Discovery of XO-6b: A Hot Jupiter Transiting a Fast Rotating F5 Star on an Oblique Orbit". The Astronomical Journal. 153 (3): 94. arXiv:1612.02776. Bibcode:2017AJ....153...94C. doi:10.3847/1538-3881/153/3/94. ISSN 1538-3881.
- McCullough, P. R.; et al. (2006). "A Transiting Planet of a Sun-like Star". The Astrophysical Journal. 648 (2): 1228–1238. arXiv:astro-ph/0605414. Bibcode:2006ApJ...648.1228M. doi:10.1086/505651. S2CID 8100425.
- 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. S2CID 13468914.
- Johns-Krull, Christopher M.; et al. (2008). "XO-3b: A Massive Planet in an Eccentric Orbit Transiting an F5V Star". The Astrophysical Journal. 677 (1): 657–670. arXiv:0712.4283. Bibcode:2008ApJ...677..657J. doi:10.1086/528950. S2CID 15342571.
- McCullough, P. R.; et al. (2008). "XO-4b: An Extrasolar Planet Transiting an F5V Star". arXiv:0805.2921 [astro-ph].
- Burke, Christopher J.; et al. (2008). "XO-5b: A Transiting Jupiter-sized Planet with a 4 day Period". The Astrophysical Journal. 686 (2): 1331–1340. arXiv:0805.2399. Bibcode:2008ApJ...686.1331B. doi:10.1086/591497. S2CID 14043772.
- Crouzet, N.; et al. (2017). "Discovery of XO-6b: A Hot Jupiter Transiting a Fast Rotating F5 Star on an Oblique Orbit". The Astronomical Journal. 153 (3). 94. arXiv:1612.02776. Bibcode:2017AJ....153...94C. doi:10.3847/1538-3881/153/3/94. S2CID 119082666.
External links
- The XO Project website
- The XO Project website
- Astronomers Catch Planet By Unusual Means (SpaceDaily) May 19, 2006