TheXO Projectis an international team of amateur and professional astronomers tasked with identifying extrasolar planets. They are led byPeter R. McCulloughof theSpace Telescope Science Institute.[1]It is primarily funded byNASA'sOrigins 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 (thetransit 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 theUniversity of TexasMcDonald Observatoryto 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 theXO 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-millimetertelephoto camera lenses,and resemblesbinocularsin shape. It is similar to theTrESsurvey telescope. It stands on the summit of theHaleakalāvolcano and 3,054 m (10,000 foot) inHawaii.[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, 2006on Newswise.
In 2016 three similar double telescopes were operating, two in Spain and one in Utah.[5]
Discoveries
editTheXO telescopehas discovered six objects so far, five arehot Jupiterplanets and one,XO-3b,may be abrown 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 | 16h02m12s | +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 | 07h48m07s | +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 | 04h21m53s | +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 | 07h21m33.1657s | +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 | 07h46m51.959s | +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 | 6h19m10.31s | +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 | 18h29m52.30s | 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 theNASA Exoplanet Archive.
Other Ground-Based Transit Surveys
editReferences
edit- ^abAstronomers Catch Planet By Unusual Means,Space Daily
- ^abXO-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.S2CID16972795.
- ^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.ISSN1538-3881.
- ^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.S2CID8100425.
- ^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.S2CID13468914.
- ^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.S2CID15342571.
- ^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.S2CID14043772.
- ^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.S2CID119082666.
External links
edit- The XO Project website
- The XO Project website
- Astronomers Catch Planet By Unusual Means(SpaceDaily) May 19, 2006