Omega Orionis

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Omega Orionis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Orion
Right ascension 05h 39m 11.14632s [1]
Declination +04° 07′ 17.2795″ [1]
Spectral type B3IIIe [1]

Omega Orionis (ω Ori) is a B3IIIe class star in the constellation Orion. Its apparent magnitude is 4.57 an is located approximately 1380 light years from our solar system, giving it an apparent magnitude of -3,56. It is surrounded by a cloud of dust, forming a modest reflection nebula over a light-year wide.[2]

Orion constellation map.

Omega Orionis is a blue giant of spectral type B3IIIe with an effective temperature of 19,100 K. Including a large amount of ultraviolet radiation, Omega Orionis shines with a Luminosity 15,275 times greater than the Sun's and it has a radius 11.4 times larger than solar radius, The projected rotation speed is-181km / s- involves a period of less than 3.15 days rotation. However, actual rotation speed can reach 450 km / s, it estimated that its axis is inclined 24° relative to the line of sight. The star has a mass 10.5 times that of the Sun, just above the limit beyond which stars explode as supernovas. Its age is estimated at 19 million years and has only recently begun his career as gigante.[3]

As a result of its rapid rotation, Omega Orionis is a Be class star. Among the stars of this class, Omega Orionis was the first where the magnetic field was measured and found to be 1000 times that of the Earth. Omega Orionis is, like many Be stars, a variable star whose brightness varies 0.19 magnitudes. Also, small variations have been observed due to non-radial pulsations with periods of 0,97 and 2,19 days.[4][5]