25 Orionis
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Orion |
| Right ascension | 05h 24m 44.82738s |
| Declination | +01° 50′ 47.2019″ |
| Apparent magnitude (V) | 4.92 - 4.96 |
| Characteristics | |
| Spectral type | B1Vn |
| U−B color index | −0.92 |
| B−V color index | −0.20 |
| Variable type | γ Cas |
| Astrometry | |
| Radial velocity (Rv) | 19.3 ± 2 km/s |
| Proper motion (μ) | RA: +1.047 mas/yr Dec.: +0.433 mas/yr |
| Parallax (π) | 2.9321±0.1219 mas |
| Distance | 1,110 ± 50 ly (340 ± 10 pc) |
| Details | |
| Mass | 10.5 M☉ |
| Radius | 6.4 R☉ |
| Luminosity | 10,500 L☉ |
| Surface gravity (log g) | 4.0 cgs |
| Temperature | 24,661 ± 339 K |
| Rotational velocity (v sin i) | 316 km/s |
| Age | ~100 Myr |
| Other designations | |
| ψ1 Ori, 25 Ori, V1086 Ori, BD+01 1005, FK5 2406, HD 35439, HIP 25302, HR 1789, SAO 112734, CCDM J05247+0150A | |
| Database references | |
| SIMBAD | data |
25 Orionis, less commonly known by its Bayer designation Psi1 Orionis (ψ1 Orionis, ψ1 Ori) is a fifth-magnitude star in the constellation Orion. It lies among a dense cluster of low-mass pre-main-sequence stars in the Orion OB1a.