Pi1_Orionis
Pi1 Orionis
Star in the constellation Orion
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.
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]