HR 4458

HR 4458 (HD 100623) is a binary star system 31.18 light-years away in the equatorial constellation of Hydra. It has the Flamsteed designation 20 Crateris and the Gould designation 289 G. Hydrae; the former refers to the constellation Crater, but when the IAU formally defined constellation boundaries, it was placed in Hydra. This object is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.97. It is moving closer to the Earth with a heliocentric radial velocity of −22 km/s.

The primary component is a K-type main-sequence star with a stellar classification of K0 V. It is around five billion years old with 84% of the Sun's radius. The star is radiating 37% of the Sun's luminosity from its photosphere at an effective temperature of 5,241 K. It has been examined for the presence of an infrared excess, but none was detected.

There is a 15th-magnitude common proper motion companion at an angular separation of 16.2″, corresponding to a projected separation of 162.5 AU. This is a white dwarf star with a classification of DC8. The orbital period of the pair is estimated as 1,110 years.

Notes

References

External links

• "CD-32 8179 / HR 4458 AB". SolStation. Archived from the original on 2012-10-13. Retrieved 2007-06-06.