HAT-P-38
| Observation data Epoch J2000.0 (ICRS) Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Triangulum |
| Right ascension | 02h 21m 31.98035s |
| Declination | +32° 14′ 46.0933″ |
| Apparent magnitude (V) | 12.51±0.02 |
| Characteristics | |
| Spectral type | G5 |
| B−V color index | +0.83 |
| Astrometry | |
| Radial velocity (Rv) | −19.85±0.73 km/s |
| Proper motion (μ) | RA: +47.671 mas/yr Dec.: −21.594 mas/yr |
| Parallax (π) | 3.9747±0.0134 mas |
| Distance | 821 ± 3 ly (251.6 ± 0.8 pc) |
| Details | |
| Mass | 0.886±0.044 M☉ |
| Radius | 1.01+0.07 −0.05 R☉ |
| Luminosity | 0.6772+0.007 −0.008 L☉ |
| Surface gravity (log g) | 4.46±0.08 cgs |
| Temperature | 5,330±100 K |
| Metallicity [Fe/H] | +0.06±0.10 dex |
| Rotational velocity (v sin i) | 0.4±0.5 km/s |
| Age | 10.1+3.9 −4.8 Gyr |
| Other designations | |
| Horna, TOI-3681, TIC 285272237, GSC 02314-00559 | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HAT-P-38, formally named Horna, is a star located in the northern constellation Triangulum. It has an apparent magnitude of 12.51, making it readily visible in amateur telescopes but not to the naked eye. The object is located relatively far at a distance of 821 light-years based on Gaia DR3 parallax measurements, but it is drifting closer with a spectroscopic radial velocity of −19.85 km/s.
HAT-P-38 has a stellar classification of G5, indicating that it is a G-type star. It has 88.6% the mass of the Sun and 101% the radius of the Sun. It radiates 67.72% the luminosity of the Sun from its photosphere at an effective temperature of 5,330 K, giving it a yelllowish-orange hue. HAT-P-38 is slightly metal enriched with an iron abundance 115% that of the Sun's. It is estimated to be approximately 10.1 billion years old, which is more than twice the age of the Sun. It spins modestly with a projected rotational velocity of 0.4 km/s.