S Cancer ( lat. S Cancri , S Cnc) is a completely eclipsing variable star of the Algol type . It is located in the constellation Cancer , at a distance of about 1000 light-years from the Sun. Outside the eclipse phases, the apparent magnitude is 8.35 m (not visible to the naked eye), and decreases to 10.3 m during the eclipse. The orbital period of the pair is 9.484 days. The main component of the pair is a white-blue star of the main sequence of class B9 with a surface temperature of 10 190 K , a radius of 2.23 R ☉ and a mass of 2.42 M ☉ . Its satellite is an orange giant or a subgiant of spectral class from G9 to K0 with a surface temperature of 4858 K , a radius of 4.74 R ☉ and a mass of 0.23 M ☉ . The mass ratio of hot and cold stars is unusually small, 0.078 ± 0.016. Signs of the flow of matter between the stars are not observed. The distance between them is 18.159 × 10 6 km , or 26.09 R ☉ . The luminosity of the hot and cold stars is 1.69 and 1.08 L ☉, respectively.
| S Cancer | |||
|---|---|---|---|
| Star | |||
| Observational data ( Age J2000.0 ) | |||
| Right ascension | |||
| Declination | |||
| Distance | 1,025 ± 114 St. years (314 ± 35 pc ) | ||
| Visible magnitude ( V ) | 8.35 [1] | ||
| Constellation | Crayfish | ||
| Astrometry | |||
| Radial velocity ( R v ) | 10 ± 4,5 [1] km / s | ||
| Own movement (μ) | RA: −19.430 (74) [1] Dec: +2,442 (38) [1] | ||
| Parallax (π) | 3.18 ± 0.35 [1] mas | ||
| Absolute magnitude (V) | 0.87 | ||
| Specifications | |||
| Spectral class | B9V + K0IV | ||
| Variability | eclipsing type Algol | ||
| physical characteristics | |||
| Weight | 2.42 + 0.23 M ☉ | ||
| Temperature | 10 190 K / 4858 K | ||
| Luminosity | 1.69 + 1.08 L ☉ | ||
| Metallicity | [M / H] =? | ||
| |||
| Database Information | |||
| SIMBAD | data | ||
See also
- Cancer constellation star list
Literature
- Irwin JB The differential limb darkening of S Cancri // Publications of the Goethe Link Observatory of Indiana University. - 1963. - P. 1104-1111. - .
- Linnell AP, Proctor DD A Computer Solution of the Light Curves of S Cancri (Eng.) // The Astrophysical Journal. - 1971. - Vol. 164. - P. 131-136. - DOI : 10.1086 / 150824 . - .
- Olson EC, Etzel PB S Cancri - New multicolor photometric observations and solutions, and spectroscopic observations (Eng.) // The Astronomical Journal. - 1993. - Vol. 106. - P. 1162-1173. - DOI : 10.1086 / 116715 . - .
Links
Notes
- ↑ 1 2 3 4 5 SIMBAD: S Cancri
- ↑ 1 2 3 4 Gaia Data Release 2 - 2018.