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Psi Crateris
Psi Crateris, Latinized from ψ Crateris, is the Bayer designation for a visual binary star system in the southern constellation of Crater. It is faintly visible to the naked eye with an apparent visual magnitude of 6.13. According to the Bortle scale, it requires dark suburban or rural skies to view. Based upon an annual parallax shift of 6.5 mas, the system is located approximately 500 light years away from the Sun. The components in this star system have an orbital period of about 366 years with an eccentricity of 0.43. The angular size of the orbit's semimajor axis is about half an arc second. The primary member, component A, is an ordinary A-type main sequence star with a visual magnitude of 6.24 and a stellar classification of A0 V. It was a candidate λ Boötis star, but this was later rejected when the spectrum was found to be normal. Any peculiarities may have instead resulted from the overlapping spectra of the two stars. The star is ... [...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] |