Kappa Cassiopeiae
Observation data Epoch J2000.0 Equinox J2000.0 | |
---|---|
Constellation | Cassiopeia |
Right ascension | 00h 32m 59.991s[1] |
Declination | +62° 55′ 54.42″[1] |
Apparent magnitude (V) | 4.189 |
Characteristics | |
Spectral type | B1Iae |
Apparent magnitude (U) | 3.50 |
Apparent magnitude (B) | 4.276 |
Apparent magnitude (J) | 4.141 |
Apparent magnitude (H) | 4.148 |
Apparent magnitude (K) | 4.013 |
U−B color index | -0.776 |
B−V color index | +0.0869 |
J−H color index | -0.0069 |
J−K color index | +0.128 |
Variable type | α Cyg |
Astrometry | |
Radial velocity (Rv) | -2.3 km/s |
Proper motion (μ) | RA: 3.65 ± 0.17[1] mas/yr Dec.: –2.07 ± 0.16[1] mas/yr |
Parallax (π) | 0.73 ± 0.17[1] mas |
Distance | approx. 4,000 ly (approx. 1,400 pc) |
Absolute magnitude (MV) | -6.32 |
Details | |
Radius | 41.4[2] R☉ |
Luminosity | 330,000[2] L☉ |
Surface gravity (log g) | 2.6[2] cgs |
Temperature | 21,500[2] K |
Rotational velocity (v sin i) | 91[2] km/s |
Other designations | |
Kappa Cassiopeiae (κ Cas, κ Cassiopeiae) is a star in the constellation Cassiopeia.
κ Cassiopeiae is a blue-white B-type supergiant with a mean apparent magnitude of +4.17. It is approximately 4000 light years from Earth.[1] It is classified as an Alpha Cygni type variable star and its brightness varies from magnitude +4.22 to +4.30.
It is a runaway star, moving at around 2.5 million mph relative to its neighbors (1,100 kilometers per second). Its magnetic field and wind of particles creates a visible bow shock 4 light-years ahead of it, colliding with the diffuse, and usually invisible, interstellar gas and dust. This is about the same distance that we are from Proxima Centauri, the nearest star to the sun.[3] [4]
References
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.Vizier catalog entry
- ↑ 2.0 2.1 2.2 2.3 2.4 Crowther, P. A.; Lennon, D. J.; Walborn, N. R. (January 2006), "Physical parameters and wind properties of galactic early B supergiants", Astronomy and Astrophysics 446 (1): 279–293, arXiv:astro-ph/0509436, Bibcode:2006A&A...446..279C, doi:10.1051/0004-6361:20053685
- ↑ Clavin, Whitney. "The bow shock of Kappa Cassiopeiae, a massive, hot supergiant". Phys.org.
- ↑ http://www.nasa.gov/jpl/spitzer/bow-shock-wave-20140220/#.Uwd-BVNfQpQ
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