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] |
Orbit [4] | |
Primary | WASP-2A |
Companion | WASP-2B |
Semi-major axis (a) | 106″ |
Characteristics | |
Spectral type | K1.5V + K2-M3 [5] |
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 mas [2] |
Distance | 502 ± 5
ly (154 ± 2 pc) |
Details [6] | |
WASP-2A | |
Mass | 0.843±0.033 M☉ |
Radius | 0.821±0.013 R☉ |
Temperature | 5170±60 K |
Age | 7.6+2.5 −3.3 Gyr |
WASP-2B | |
Mass | 0.48 [1] M☉ |
Temperature | 3523+28 −19 K |
Other designations | |
Database references | |
SIMBAD | data |
WASP-2 is a binary star system in the Delphinus constellation located about 500 light-years away. [3] The primary is magnitude 12 orange dwarf star, orbited by red dwarf star on wide orbit. [4] [7] The star system shows an infrared excess noise of unknown origin. [8]
This star has one extrasolar planet WASP-2b, detected by the SuperWASP project in 2006. [9]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 0.882±0.027 MJ | 0.0308±0.0004 | 2.15222144 (± 4e-07) | 0 | — | 1.06±0.024 RJ |
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. [10]
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] |
Orbit [4] | |
Primary | WASP-2A |
Companion | WASP-2B |
Semi-major axis (a) | 106″ |
Characteristics | |
Spectral type | K1.5V + K2-M3 [5] |
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 mas [2] |
Distance | 502 ± 5
ly (154 ± 2 pc) |
Details [6] | |
WASP-2A | |
Mass | 0.843±0.033 M☉ |
Radius | 0.821±0.013 R☉ |
Temperature | 5170±60 K |
Age | 7.6+2.5 −3.3 Gyr |
WASP-2B | |
Mass | 0.48 [1] M☉ |
Temperature | 3523+28 −19 K |
Other designations | |
Database references | |
SIMBAD | data |
WASP-2 is a binary star system in the Delphinus constellation located about 500 light-years away. [3] The primary is magnitude 12 orange dwarf star, orbited by red dwarf star on wide orbit. [4] [7] The star system shows an infrared excess noise of unknown origin. [8]
This star has one extrasolar planet WASP-2b, detected by the SuperWASP project in 2006. [9]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 0.882±0.027 MJ | 0.0308±0.0004 | 2.15222144 (± 4e-07) | 0 | — | 1.06±0.024 RJ |
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. [10]