BD+20 2457: Difference between revisions
proposed planetary system is dynamically implausible |
proposed merger from BD+20°2457 b and BD+20°2457 c |
||
| Line 1: | Line 1: | ||
{{Merge from|BD+20°2457 b|BD+20°2457 c|discuss=Talk:BD+20°2457#Merger proposal|date=March 2014}} |
|||
{{Starbox begin |
{{Starbox begin |
||
| name = [[Durchmusterung|BD]]+20°2457 |
| name = [[Durchmusterung|BD]]+20°2457 |
||
Revision as of 21:39, 30 March 2014
 | It has been suggested that BD+20°2457 b and BD+20°2457 c be merged into this article. (Discuss) Proposed since March 2014. |
 Artistic rendering of star BD+20° 2457, how it appears at ≈4 Astronomical Units. | |
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Leo |
| Right ascension | 10h 16m 44.8635s |
| Declination | +19° 53′ 28.974″ |
| Apparent magnitude (V) | 9.75 |
| Characteristics | |
| Spectral type | K2II |
| B−V color index | 1.18 |
| Variable type | none |
| Astrometry | |
| Proper motion (μ) | RA: –35.20 mas/yr Dec.: –31.70 mas/yr |
| Parallax (π) | 5.00 ± 3.33 mas |
| Distance | 650 ± 330 ly (200 ± 100 pc) |
| Details | |
| Mass | 2.8 ± 1.5[1] M☉ |
| Radius | 49[1] R☉ |
| Luminosity | 624 L☉ |
| Surface gravity (log g) | 2.5 cgs |
| Temperature | 4127 ± 17[1] K |
| Metallicity | –1.00 ± 0.07 |
| Other designations | |
PPM 127264 | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
BD+20°2457 is a 10th magnitude K-type bright giant star located between 320 to 980 light years away in the constellation of Leo. This star is very metal-poor, containing only 10% as enriched with elements heavier than hydrogen and helium as our sun, almost classifying this as a population II star. On June 10, 2009, two planets were announced to be orbiting the star, with minimum masses 21.4 and 12.5 times the mass of Jupiter and orbital periods of 380 and 622 days for the inner and outer planets respectively.[1] A dynamical analysis reveals that the proposed system is unstable on astronomically-short timescales and so the suggested planetary configuration is unlikely to be correct: further data is needed to determine a physically-plausible explanation for the radial velocity variations.[2]
References
- ^ a b c d Niedzielski, A.; et al. (2009). "Substellar-mass Companions to the K-dwarf BD+14 4559 and the K-giants HD 240210 and BD+20 2457". The Astrophysical Journal. 707 (1): 768–777. arXiv:0906.1804. Bibcode:2009ApJ...707..768N. doi:10.1088/0004-637X/707/1/768.
- ^ Horner, J.; Wittenmyer, R. A.; Hinse, T. C.; Marshall, J. P. (2014). "A dynamical investigation of the proposed BD +20 2457 system". Monthly Notices of the Royal Astronomical Society. 439 (1): 1176–1181. arXiv:1401.2793. Bibcode:2014MNRAS.439.1176H. doi:10.1093/mnras/stu081.
{{cite journal}}: CS1 maint: multiple names: authors list (link) CS1 maint: unflagged free DOI (link)
| Stars |
| ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| |||||||||||||
| Galaxies |
| ||||||||||||
 | This giant-star-related article is a stub. You can help Wikipedia by expanding it. |
 | This extrasolar-planet-related article is a stub. You can help Wikipedia by expanding it. |