Back HR 8799 Afrikaans HR 8799 Arabic HR 8799 AST এইচআর ৮৭৯৯ Bengali/Bangla HR 8799 Catalan HR 8799 Czech HR 8799 German HR 8799 Spanish اچآر ۸۷۹۹ Persian HR 8799 Finnish
 HR 8799 (center) with HR 8799 e (right), HR 8799 d (lower right), HR 8799 c (upper right), HR 8799 b (upper left) from W. M. Keck Observatory | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Pegasus |
| Right ascension | 23h 07m 28.7157s[1] |
| Declination | +21° 08′ 03.311″[1] |
| Apparent magnitude (V) | 5.964[2] |
| Characteristics | |
| Spectral type | kA5 hF0 mA5 V; λ Boo[3][4] |
| U−B color index | −0.04[5] |
| B−V color index | 0.234[2] |
| Variable type | Gamma Doradus variable[2] |
| Astrometry | |
| Radial velocity (Rv) | −11.5±2[2] km/s |
| Proper motion (μ) | RA: 108.284±0.056[1] mas/yr Dec.: −50.040±0.059[1] mas/yr |
| Parallax (π) | 24.4620 ± 0.0455 mas[1] |
| Distance | 133.3 ± 0.2 ly (40.88 ± 0.08 pc) |
| Absolute magnitude (MV) | 2.98±0.08[3] |
| Details | |
| Mass | 1.43+0.06 −0.07[6] M☉ |
| Radius | 1.34±0.05[3] R☉ |
| Luminosity (bolometric) | 4.92±0.41[3] L☉ |
| Surface gravity (log g) | 4.35±0.05[3] cgs |
| Temperature | 7430±75[3] K |
| Metallicity [Fe/H] | −0.52±0.08[7][a] dex |
| Rotational velocity (v sin i) | 37.5±2[3] km/s |
| Age | 30+20 −10[8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HR 8799 is a roughly 30 million-year-old main-sequence star located 133.3 light-years (40.9 parsecs) away from Earth in the constellation of Pegasus. It has roughly 1.5 times the Sun's mass and 4.9 times its luminosity. It is part of a system that also contains a debris disk and at least four massive planets. Those planets, along with Fomalhaut b, were the first exoplanets whose orbital motion was confirmed by direct imaging. The star is a Gamma Doradus variable: its luminosity changes because of non-radial pulsations of its surface. The star is also classified as a Lambda Boötis star, which means its surface layers are depleted in iron peak elements. It is the only known star which is simultaneously a Gamma Doradus variable, a Lambda Boötis type, and a Vega-like star (a star with excess infrared emission caused by a circumstellar disk).
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Yale-BSC-1991-06was invoked but never defined (see the help page). - ^ Sepulveda, Aldo G.; Bowler, Brendan P. (2022). "Dynamical Mass of the Exoplanet Host Star HR 8799". The Astronomical Journal. 163 (2): 52. arXiv:2111.12090. Bibcode:2022AJ....163...52S. doi:10.3847/1538-3881/ac3bb5. S2CID 232572566.
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