Tycho G
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 00h 25m 23.59578s |
| Declination | +64° 08′ 02.0297″ |
| Apparent magnitude (V) | 18.71 |
| Characteristics | |
| Evolutionary stage | subgiant |
| Spectral type | G0/1 IV |
| Astrometry | |
| Radial velocity (Rv) | −79.22 km/s |
| Proper motion (μ) | RA: −2.50 mas/yr Dec.: −4.22 mas/yr |
| Parallax (π) | 0.5189±0.0993 mas |
| Distance | approx. 6,000 ly (approx. 1,900 pc) |
| Details | |
| Mass | 1.0 M☉ |
| Radius | 1.32–2.63 R☉ |
| Luminosity | 1.9–7.6 L☉ |
| Surface gravity (log g) | 4.0 cgs |
| Temperature | 6,025 K |
| Metallicity | −0.13 |
| Rotational velocity (v sin i) | < 6 km/s |
| Age | 5.7 Gyr |
| Other designations | |
| Tycho G, 2MASS J00252358+6408019 | |
| Database references | |
| SIMBAD | data |
Tycho G has been proposed as the surviving binary companion star of the SN 1572 supernova event. The star is located about 6,500±1,300 light-years away in the constellation Cassiopeia. It is a subgiant, similar to the Sun in temperature, but more evolved and luminous.