Pi1 Orionis (π1 Ori, π1 Orionis) is a star in the equatorial constellation of Orion. It is faintly visible to the naked eye with an apparent visual magnitude of 4.74.[2] Based upon an annual parallax shift of 28.04 mas,[1] it is located about 116 light-years from the Sun.
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Orion |
Right ascension | 04h 54m 53.72877s[1] |
Declination | +10° 09′ 02.9952″[1] |
Apparent magnitude (V) | 4.74[2] |
Characteristics | |
Spectral type | A3 Va[3] |
U−B color index | +0.09[2] |
B−V color index | +0.08[2] |
Astrometry | |
Proper motion (μ) | RA: +41.49[1] mas/yr Dec.: −128.73[1] mas/yr |
Parallax (π) | 28.04 ± 0.25 mas[1] |
Distance | 116 ± 1 ly (35.7 ± 0.3 pc) |
Absolute magnitude (MV) | 1.76±0.08[4] |
Details | |
Mass | 1.97±0.07[4] M☉ |
Radius | 1.67[5] R☉ |
Luminosity | 16.6[5] L☉ |
Surface gravity (log g) | 4.15[3] cgs |
Temperature | 8,611[3] K |
Metallicity [Fe/H] | −1.24[3] dex |
Rotational velocity (v sin i) | 120[6] km/s |
Age | 100[5] Myr |
Other designations | |
Database references | |
SIMBAD | data |
This is an A-type main-sequence star with a stellar classification of A3 Va.[3] It is a Lambda Boötis star,[8] which means the spectrum shows lower-than-expected abundances for heavier elements.[9] Pi1 Orionis is a relatively young star, just 100 million years old,[5] and is spinning fairly rapidly with a projected rotational velocity of 120 km/s.[6] It has nearly double[4] the mass of the Sun and 167% of the Sun's radius. The star radiates 16.6[5] times the solar luminosity from its outer atmosphere at an effective temperature of 8,611 K.[3]
An infrared excess indicates there is a debris disk with a temperature of 80 K orbiting 49 AU from the star. The dust has a combined mass 2.2% that of the Earth.[5]
{{cite web}}
: CS1 maint: postscript (link)