WASP-2

WASP-2 is a magnitude 12 orange dwarf star located about 500 light-years away in the Delphinus constellation.[3] It shows an infrared excess noise of unknown origin.[5]

WASP-2
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Delphinus
A[1]
Right ascension  20h 30m 54.1279s[2]
Declination +06° 25′ 46.338″[2]
Apparent magnitude (V) +11.98[3]
C[a 1]
Right ascension ~ 20h 30m 54s[1]
Declination ~+06° 25′ 46″[1]
Apparent magnitude (V) 15.38[1]
Characteristics
Spectral type K1V[4]/M[1]
Apparent magnitude (B) ~13[3]
Apparent magnitude (V) ~11.98[3]
Apparent magnitude (J) 10.166±0.027[3]
Apparent magnitude (H) 9.752±0.026[3]
Apparent magnitude (K) 9.632±0.024[3]
Astrometry
Proper motion (μ) RA: 5.936±0.101[2] mas/yr
Dec.: −48.279±0.082[2] mas/yr
Parallax (π)6.4980 ± 0.0686[2] mas
Distance502 ± 5 ly
(154 ± 2 pc)
Details
Mass0.77[1]/0.48[1] M☉
Radius0.834 ±0.08 R☉
Temperature5200 ±200 K
Other designations
GSC 00522-01199, 1SWASP J203054.12+062546.4, USNO-B1.0 0964-00543604, 2MASS J20305413+0625463, UCAC2 34018636, Gaia DR2 1748596020745038208
Database references
SIMBADdata
Extrasolar Planets
Encyclopaedia		data

Planetary system

This star has one extrasolar planet WASP-2b, detected by the SuperWASP project in 2006.[4]

The WASP-2 planetary system
Companion
(in order from star)		 Mass Semimajor axis
(AU)		 Orbital period
(days)		 Eccentricity Inclination Radius
b 0.847 (± 0.045) MJ 0.03138 (± 0.011) 2.15222144 (± 4e-07) 0 — —

Binary star

In 2008 a study was undertaken of fourteen stars with exoplanets that were originally discovered using the transit method through relatively small telescopes. These systems were re-examined with the 2.2 m (87 in) reflector telescope at the Calar Alto Observatory in Spain. This star system, along with two others, was determined to be a previously unknown binary star system. The previously unknown secondary star is a dim magnitude 15 M-type star separated by about 111 AU from the primary, appearing offset from the primary by about one arc second in the images. This discovery resulted in a recalculation of parameters for both the planet and the primary star.[1]

The re-examination of the WASP-2 spectrum in 2015, have resulted in the measurement of stellar companion temperature equal to 3513±28 K, and angular separation of 0.73 arc second[6]

See also

Notes
  1. The secondary star is identified with a "C" suffix so as to not confuse it with the planetary designation suffix "b".[1]

References
  1. Daemgen; et al. (2009). "Binarity of transit host stars - Implications for planetary parameters" (PDF). Astronomy and Astrophysics. 498 (2): 567–574. arXiv:0902.2179. Bibcode:2009A&A...498..567D. doi:10.1051/0004-6361/200810988.
  2. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
  3. "WASP-2". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2009-05-04.
  4. Cameron, A. Collier; et al. (2007). "WASP-1b and WASP-2b: two new transiting exoplanets detected with SuperWASP and SOPHIE". Monthly Notices of the Royal Astronomical Society. 375 (3): 951–957. arXiv:astro-ph/0609688. Bibcode:2007MNRAS.375..951C. doi:10.1111/j.1365-2966.2006.11350.x.
  5. EXTRASOLAR PLANET TRANSITS OBSERVED AT KITT PEAK NATIONAL OBSERVATORY, 2012, arXiv:1202.2799
  6. FRIENDS OF HOT JUPITERS III:AN INFRARED SPECTROSCOPIC SEARCH FOR LOW-MASS STELLAR COMPANIONS, 2015, arXiv:1510.08062
  • "WASP-2". Exoplanets. Retrieved 2009-05-04.

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.