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
editPreliminary 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
editMcCullough 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
editThe 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
editA subset of XO light curves are available at the NASA Exoplanet Archive.
Other Ground-Based Transit Surveys
edit- Next-Generation Transit Survey
- Trans-Atlantic Exoplanet Survey or TrES
- HATNet Project or HAT
- Kilodegree Extremely Little Telescope or KELT
- SuperWASP or WASP
References
edit- ^ a b Astronomers Catch Planet By Unusual Means, Space Daily
- ^ a b 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
edit- The XO Project website
- The XO Project website
- Astronomers Catch Planet By Unusual Means (SpaceDaily) May 19, 2006