Mu Cassiopeiae
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| Observation data Epoch J2000 |
|
|---|---|
| Constellation | Cassiopeia |
| Right ascension | 01h08m16.4s |
| Declination | +54°55′13″ |
| Apparent magnitude (V) | 5.17/11 |
| Spectral Characteristics | |
| Spectral type | G5VIp/M5V |
| U-B color index | 0.10 |
| B-V color index | 0.69 |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | -98.1 km/s |
| Proper motion (μ) | RA: 3,421.44 mas/yr Dec.: -1,599.27 mas/yr |
| Parallax (π) | 132.57 ± 0.57 mas |
| Distance | 24.6 ± 0.1 ly (7.54 ± 0.03 pc) |
| Absolute magnitude (MV) | 5.78/11.6 |
| Visual binary orbit | |
| Companion | μ Cas B |
| Period (P) | 21.40 years |
| Semimajor axis (a) | 0.189" |
| Eccentricity (e) | 0.62 |
| Inclination (i) | 110.0° |
| Node (Ω) | 227.3° |
| Periastron epoch (T) | 1975.80 |
| Physical Characteristics | |
| Mass | 0.60/0.17 M☉ |
| Radius | 0.74/0.29 R☉ |
| Luminosity | 0.46/0.001 L☉ |
| Temperature | 5290 K |
| Metallicity | 13-28% |
| Rotation | ? |
| Age | 7.9 × 109 years |
| Other designations | |
Mu Cassiopeiae (μ Cas / μ Cassiopeiae) is a binary star system in the constellation Cassiopeia. This system shares the name Marfak with Theta Cassiopeiae.
In 1961 the close binary nature of this system was discovered. Since then the orbital elements of the two stars have been fairly well established. The two stars are separated by a distance range of 0.54–2.30 AU. Compared to other nearby stars, this pair are moving at a relatively high velocity of 167 km/s through the Milky Way galaxy. They are low metal, Population II stars that are thought to have formed before the galactic disk first appeared.
[edit] References
- Heintz, W. D.; Cantor, B. A. (1994). "An astrometric study of four binary stars". PASP 106: 363–364.
[edit] External links
- SolStation entry
- Mu Cassiopeiae by Professor Jim Kaler.
