Kappa¹ Ceti
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| Observation data Epoch J2000 |
|
|---|---|
| Constellation (pronunciation) |
Cetus |
| Right ascension | 03h 19m 21.7s |
| Declination | +03° 22′ 13″ |
| Apparent magnitude (V) | 4.84 |
| Characteristics | |
| Spectral type | G5 V |
| U-B color index | 0.19 |
| B-V color index | 0.67 |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | +19.9 km/s |
| Proper motion (μ) | RA: 268.87 mas/yr Dec.: 93.53 mas/yr |
| Parallax (π) | 109.18 ± 0.78 mas |
| Distance | 29.9 ± 0.2 ly (9.16 ± 0.07 pc) |
| Absolute magnitude (MV) | 5.03 |
| Details | |
| Mass | 0.9 M☉ |
| Radius | .96 R☉ |
| Luminosity | 0.85 L☉ |
| Temperature | 5,690 K |
| Metallicity | 110% Sun |
| Rotation | 8.9-10.5 days (4.64 km/s.) |
| Age | 6.5-7.5 × 108 years |
| Other designations | |
Kappa1 Ceti is a single star in the constellation Cetus the Whale. It is slightly less massive than our Sun, giving it a lower temperature and a redder hue. This star has been examined for companions, thus far without success. There was some early evidence based on spectroscopic measurements, but subsequent examination failed to corroborate the earlier results.
The rapid rotation rate of this star, roughly once every 9 days, is indicative of a relatively youthful body several hundred million years in age. Due to starspots, the star varies slightly over the approximately the same period. (The variations in period are thought to be caused by differential rotation at various latitudes, similar to what happens on the surface of our Sun.[1])
This star been observed to emit what is termed a "super flare", a type of large-scale mass ejection event. These are 108-109 more energetic than a typical coronal mass ejection on the Sun.[2] Such events would have serious implications for the environments of potential planetary bodies in orbit around this star.
Kappa2 Ceti is a star that lies near the line of sight of Kappa1 Ceti, but is about 10 times further away from us. It is a giant star of spectral class G8.
[edit] References
- ^ E. J. Gaidos, G.W. Henry, S.M.Henry, 2000, "Spectroscopy and Photometry of Nearby Young Solar Analogs", The Astronomical Journal, 120:1006-1013.
- ^ B. E. Schaefer, J.R. King, C.P. Deliyannis, 2000, "Superflares on Ordinary Solar-Type Stars", The Astrophysical Journal, Vol. 529, Issue 2, pp. 1026-1030.
[edit] External links
- Kappa Ceti at SolStation.
- ESA
- Kappa-1 Ceti by Professor Jim Kaler.
- ARICNS entry
