Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Pegasus |
Right ascension | 22h 52m 09.8636s [1] |
Declination | +35° 26′ 49.608″ [1] |
Apparent magnitude (V) | 10.17 [2] |
Characteristics | |
Spectral type | F [3] |
Apparent magnitude (B) | 10.77 ± 0.04 [2] |
Apparent magnitude (V) | 10.36 ± 0.03 [2] |
Apparent magnitude (J) | 9.214 ± 0.022 [2] |
Apparent magnitude (H) | 9.004 ± 0.018 [2] |
Apparent magnitude (K) | 8.953 ± 0.013 [2] |
Variable type | planetary transit [3] |
Astrometry | |
Radial velocity (Rv) | −22.2±0.3 [1] km/s |
Proper motion (μ) |
RA: 74.676(19)
mas/
yr
[1] Dec.: 14.944(20) mas/ yr [1] |
Parallax (π) | 4.6606 ± 0.0208 mas [1] |
Distance | 700 ± 3
ly (214.6 ± 1.0 pc) |
Details | |
Mass | 1.27±0.03 [4] M☉ |
Radius | 1.491+0.016 −0.014 [4] R☉ |
Surface gravity (log g) | 4.1956+0.0095 −0.013 [4] cgs |
Temperature | 6410±140 [4] K |
Metallicity [Fe/H] | -0.018+0.0072 −0.056 [4] dex |
Rotational velocity (v sin i) | 12.6 ± 1.0 [5] km/s |
Age | 3.4 ± 1 Gyr |
Other designations | |
Database references | |
SIMBAD | data |
HAT-P-8 is a magnitude 10 star located 700 light-years away in Pegasus. [2] It is a F-type star about 28% more massive than the Sun. [3] Two red dwarf companions have been detected around HAT-P-8. The first has a spectral type of M5V and has a mass of 0.22 M☉. The second is even less massive, at 0.18 M☉, and its spectral type is M6V. [6]
In 2008 the HATNet Project announced the discovery of extrasolar planet HAT-P-8b around this star. This planet is a hot Jupiter gas giant planet. [3]
Companion (in order from star) |
Mass |
Semimajor axis ( AU) |
Orbital period ( days) |
Eccentricity | Inclination | Radius |
---|---|---|---|---|---|---|
b | 1.354±0.035 MJ | 0.04496+0.00046 −0.00045 |
3.0763458±0.0000024 | <0.0060 | — | 1.334±0.013 [4] RJ |
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