Magnitude 14.1 B−V color index +0.77 People also search for V725 Sagittarii | Temperature 210,000 K Apparent magnitude (V) 14.1 Absolute magnitude (MV) −1.71 | |
 | ||
Unboxing toys review demos gundam huge efsf white base wr 102
WR 102 is a Wolf-Rayet star in the constellation Sagittarius, an extremely rare star on the WO oxygen sequence.
Contents
Features
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 nearly 500,000 L☉ although the distance is not known with any certainty. It is a very small dense star, less than 0.4 R☉ but nearly 20 M☉.
Very strong stellar winds with a terminal velocity of 5,000 kilometers per second are causing WR 102 to lose 10−5 M☉/year. For comparison, the Sun loses (2-3) x 10−14 solar masses per year due to its solar wind, several hundred million times less than WR 102. These winds and the strong ultraviolet radiation from the hot star have compressed and ionised the surrounding interstellar material into a complex series of arcs described as the bubble type of Wolf-Rayet nebula.
Evolutionary status
WO stars are the last evolutionary stage of the most massive stars before exploding as supernovae. 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.
