| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 01h 20m 31.596s [1] |
| Declination | +61° 52′ 57.01″ [1] |
| Apparent magnitude (V) | 9.04 [2] |
| Characteristics | |
| Evolutionary stage | main sequence [1] |
| Spectral type | G3 [3] |
| Astrometry | |
| Proper motion (μ) | RA: +0.144 [1] mas/yr Dec.: +0.010 [1] mas/yr |
| Parallax (π) | 13.2118±0.0322 mas [1] |
| Distance | 246.9 ± 0.6 ly (75.7 ± 0.2 pc) |
| Details | |
| Mass | 1.07 [1] M☉ |
| Radius | 1.09 [1] R☉ |
| Luminosity | 1.20 [1] L☉ |
| Surface gravity (log g) | 4.35 [1] cgs |
| Temperature | 5,816 [1] K |
| Metallicity [Fe/H] | −0.59 [1] dex |
| Age | 6.7 [1] Gyr |
| Other designations | |
| HD 7977, BD+61°250, SAO 11703 | |
| Database references | |
| SIMBAD | data |
HD 7977 (also designated as TYC 4034-1077-1 or USNO-A2 1500-01356484) is a G-type main-sequence star located in the constellation of Cassiopeia, around 246.9 light-years away from Earth. HD 7977 is notable for its close flyby of the Solar System 2.8 million years ago. [4] Its flyby may have taken it close enough to the Sun that it penetrated deep into the Oort Cloud and disturbed the population of Oort Cloud bodies and long-period comets there. [5] Its mass is equivalent to 1.07 times the Sun's mass. [6]
