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WR 102 Star System (Wolf-Rayette)

WR 102, of spectral classification WO2, is one of the very few known oxygen-sequence Wolf–Rayet stars, just four in the Milky Way galaxy and five in external galaxies. It is also the hottest known, with a surface temperature of 210,000 K. Modelling the atmosphere gives a luminosity around 282,000 L☉, while calculations from brightness and distance gives luminosity of 380,000 L☉ with a distance of 9400 light years from the Solar System. It is a very small dense star, with a radius 0.52 R☉ and a mass of 16.7 M☉.
It is very likely that WR 102 is on its last stages of nuclear fusion, near or beyond the end of helium burning. It has been calculated that WR 102 will explode as a supernova within 1,500 years. High mass and rapid rotation would make a gamma-ray burst (GRB) possible, but it is unclear if WR 102 is rotating rapidly. It was previously thought that the projected rotation velocity within the stellar wind could be as fast as 1,000 km/s, but spectropolarimetric observations seem to indicate that if WR 102 is rotating, it is rotating at a much lower speed.[