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WR 142
WR 142 is a Wolf-Rayet star in the constellation Cygnus (constellation), Cygnus, an extremely rare star on the WO oxygen sequence. It is a luminous and very hot star, highly evolved and close to exploding as a supernova. It is suspected to be a binary star with a companion orbiting about away. Discovery In 1966, a search for Wolf-Rayet stars in the northern celestial hemisphere discovered seven new examples. One, designated as ''Stephenson 3'', was classified as WC. It was later found to show unusual emission lines of highly ionised OVI. Because of the unusual oxygen lines, seen in only a handful of other stars, it was given the spectral type WC5pec in the Sixth Catalogue of Galactic Wolf-Rayet Stars. In 1981, described as a WC-OVI star, it was identified as being associated with the active star-forming region ON2, and then a heavily obscured open cluster designated Berkeley 87, south of the red supergiant BC Cygni. In 1982, the WC-OVI stars were grouped as member ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
J2000
In astronomy, an epoch or reference epoch is a instant, moment in time used as a reference point for some time-varying astronomical quantity. It is useful for the celestial coordinates or orbital elements of a Astronomical object, celestial body, as they are subject to Perturbation (astronomy), perturbations and vary with time. These time-varying astronomical quantities might include, for example, the mean longitude or mean anomaly of a body, the node of its orbit relative to a reference plane, the direction of the apogee or Perihelion and aphelion, aphelion of its orbit, or the size of the major axis of its orbit. The main use of astronomical quantities specified in this way is to calculate other relevant parameters of motion, in order to predict future positions and velocities. The applied tools of the disciplines of celestial mechanics or its subfield orbital mechanics (for predicting orbital paths and positions for bodies in motion under the gravitational effects of other bodi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |