HD 202206
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Stern HD 202206 |
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| AladinLite | |||||||||||||
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Observation dates equinox : J2000.0 , epoch : J2000.0 |
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| Constellation | Capricorn | ||||||||||||
| Right ascension | 21 h 14 m 57.77 s | ||||||||||||
| declination | -20 ° 47 ′ 21.2 ″ | ||||||||||||
| Apparent brightness | 8.08 likes | ||||||||||||
| Typing | |||||||||||||
| Known exoplanets | 1 | ||||||||||||
| B − V color index | +0.7 | ||||||||||||
| Spectral class | G6 V | ||||||||||||
| Astrometry | |||||||||||||
| parallax | (22.06 ± 0.82) mas | ||||||||||||
| distance | (147.8 ± 5.5) ly (45.3 ± 1.7) pc |
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| Visual absolute brightness M vis | +4.80 mag | ||||||||||||
| Proper movement | |||||||||||||
| Rec. Share: | (−38.40 ± 0.94) mas / a | ||||||||||||
| Dec. portion: | (−119.81 ± 0.37) mas / a | ||||||||||||
| Physical Properties | |||||||||||||
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Other names and catalog entries |
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HD 202206 is a main sequence star of the spectral class G6 in the constellation Capricorn . It is orbited by two substellar companions.
According to measurements by the Hipparcos satellite , the star's parallax is 22 milli-arcseconds , which corresponds to a distance of 45 parsecs . The apparent visual brightness of HD 202206 is 8.1 mag. The star is around 5.4 billion years old, its mass is around 13 percent higher than that of the Sun , and its radius is almost exactly the same. It has a significantly higher metallicity than the sun.
Substellar companions
After measurements of the radial velocity, a substellar object with at least 17 times the mass of Jupiter was discovered in an orbit around the central star. The object with the designation HD 202206 b / HD 202206 B is probably a brown dwarf . HD 202206 B orbits the main sequence star in a very eccentric orbit at a mean distance of 0.8 astronomical units in 256 days .
After further measurements, the data of another companion were published in 2004. The second companion, HD 202206 c , has at least 2.4 times the mass of Jupiter and orbits HD 202206 in 1400 days on an also very eccentric orbit at a mean distance of 2.5 astronomical units. The two companions are in a 5: 1 track resonance .
Individual evidence
- ↑ a b c Hipparcos catalog (ESA 1997)
- ↑ a b c Hipparcos, the New Reduction (van Leeuwen, 2007)
- ↑ Udry, S. et al .: The CORALIE survey for southern extra-solar planets VIII. The very low-mass companions of HD 141937, HD 162020, HD 168443, HD 202206: Brown dwarfs or “superplanets”? . In: Astronomy and Astrophysics . 390, 2002, pp. 267-279.