Upsilon1 Cancri
Upsilon1 Cancri, Latinised from υ1 Cancri, is the Bayer designation for a solitary, yellow-white-hued star in the constellation Cancer. It is faintly visible with the naked eye, having an apparent visual magnitude of +5.7. Based upon an annual parallax shift of 13.05 mas as seen from Earth, this system is roughly 250 light-years from the Sun.
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Cancer |
| Right ascension | 08h 31m 30.51925s |
| Declination | +24° 04′ 51.9890″ |
| Apparent magnitude (V) | +5.694 |
| Characteristics | |
| Spectral type | F0 IIIn |
| B−V color index | +0.309 |
| Astrometry | |
| Radial velocity (Rv) | +19.0±4.3 km/s |
| Proper motion (μ) | RA: −81.36 mas/yr Dec.: −44.57 mas/yr |
| Parallax (π) | 13.05 ± 0.29 mas |
| Distance | 250 ± 6 ly (77 ± 2 pc) |
| Absolute magnitude (MV) | +1.29 |
| Details | |
| Mass | 1.47 M☉ |
| Luminosity | 25 L☉ |
| Surface gravity (log g) | 3.51 cgs |
| Temperature | 7,240±246 K |
| Rotational velocity (v sin i) | 109.2 km/s |
| Age | 570 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This object has a stellar classification of F0 IIIn, indicating it is an F-type giant star. The 'n' suffix indicates "nebulous" absorption lines due to rapid rotation, and it shows a relatively high projected rotational velocity of 109.2 km/s. It is a variable star of unknown type that varies in brightness with an amplitude of 0.05 magnitude. The star is about 570 million years old and it has an estimated mass of 1.47 times that of the Sun. On average, it is radiating 25 times the Sun's luminosity from its photosphere at an effective temperature of 7,240 K.