HAT-P-28
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Andromeda |
| Right ascension | 00h 52m 00.1876s |
| Declination | +34° 43′ 42.205″ |
| Apparent magnitude (V) | 13.03 |
| Characteristics | |
| Evolutionary stage | main sequence |
| Spectral type | G3 |
| Astrometry | |
| Radial velocity (Rv) | 48.06 km/s |
| Proper motion (μ) | RA: 25.615(14) mas/yr Dec.: 2.712(11) mas/yr |
| Parallax (π) | 2.4728±0.0156 mas |
| Distance | 1,319 ± 8 ly (404 ± 3 pc) |
| Orbit | |
| Primary | HAT-P-28 |
| Companion | HAT-P-28 B |
| Semi-major axis (a) | 0.994±0.002" (404 AU) |
| Details | |
| Mass | 1.02±0.05 M☉ |
| Radius | 1.10+0.09 −0.07 R☉ |
| Luminosity | 1.13+0.23 −0.16 L☉ |
| Surface gravity (log g) | 4.36±0.06 cgs |
| Temperature | 5680±90 K |
| Metallicity [Fe/H] | 0.12±0.08 dex |
| Rotational velocity (v sin i) | 0.2+0.5 −0.2 km/s |
| Age | 6.1+2.6 −1.9 Gyr |
| Other designations | |
| Gaia DR2 363702817083391232, GSC 02284-00503, 2MASS J00520018+3443422 | |
| Database references | |
| SIMBAD | data |
HAT-P-28 is the primary of a binary star system about 1320 light-years away. It is a G-type main-sequence star. The star's age is older than the Sun's at 6.1+2.6
−1.9 billion years. HAT-P-28 is slightly enriched in heavy elements, having a 130% concentration of iron compared to the Sun. Evolutionary modelling shows it to be right at the end of its main sequence life. The binary star system is suspected to be surrounded by a debris disk with a 6.1″(2500 AU) radius.
The red dwarf stellar companion was detected in 2015 at a projected separation of 0.972″ and confirmed in 2016 to be either bound or co-moving.