DP Leonis (abbreviated DP Leo) is a binary star system in the equatorial constellation of Leo. It is a variable star that ranges in apparent visual magnitude from 17.5 down to 19.[3] The system is located at a distance of approximately 990 light-years from the Sun based on parallax.[2] It is a cataclysmic variable star of the AM Herculis-type also known as polars. The system comprises an eclipsing white dwarf and red dwarf in tight orbit (nearly 1.5 hours) and an extrasolar planet.[8] This eclipsing variable was discovered by P. Biermann and associates in 1982 as the optical counterpart to the EINSTEIN X-ray source E1114+182.[9]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Leo |
| Right ascension | 11h 17m 15.92381s[2] |
| Declination | +17° 57′ 41.6804″[2] |
| Apparent magnitude (V) | 17.5-19[3] |
| Characteristics | |
| Variable type | AM Her[3] |
| Astrometry | |
| Radial velocity (Rv) | 0.0[4] km/s |
| Proper motion (μ) | RA: −28.700 mas/yr[2] Dec.: −1.444 mas/yr[2] |
| Parallax (π) | 3.2781 ± 0.3110 mas[2] |
| Distance | 990 ± 90 ly (310 ± 30 pc) |
| Orbit | |
| Period (P) | 0.0623628426[5] yr |
| Eccentricity (e) | 0.0 (fixed) |
| Inclination (i) | 79.5[6]° |
| Details | |
| White dwarf | |
| Mass | 0.6[6] M☉ |
| Temperature | 13,500[5] K |
| Donor star | |
| Mass | 0.09[6] M☉ |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
Planetary system edit
In 2010, Qian et al. announced the detection of a third body of planetary mass around the eclipsing binary system. The presence of a third body had already been suspected in 2002.[6] The object is roughly 6 times more massive than Jupiter and is located 8.6 AU from the binary.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥6.1 ± 0.5 MJ | 8.2 ± 0.4 | 28.0 ± 2.0 | 0.39 ± 0.13 | — | — |
See also edit
References edit
- ^ Beuermann, K.; Dreizler, S.; Hessman, F. V.; Schwope, A. D. (February 2014). "Evidence for an oscillation of the magnetic axis of the white dwarf in the polar DP Leonis". Astronomy and Astrophysics. 562: A63. arXiv:1401.1638. Bibcode:2014A&A...562A..63B. doi:10.1051/0004-6361/201323192. S2CID 118631556.
- ^ a b c d e Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv:1804.09365. Bibcode:2018A&A...616A...1G. doi:10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d Samus, N. N.; et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1. 61 (1): 80–88. Bibcode:2017ARep...61...80S. doi:10.1134/S1063772917010085. S2CID 125853869. Retrieved 2021-11-30.
- ^ Duflot, M.; et al. (December 1995). "Radial velocities: The Wilson-Evans-Batten catalogue". Astronomy and Astrophysics Supplement. 114: 269. Bibcode:1995A&AS..114..269D.
- ^ a b c Beuermann, K.; et al. (February 2011). "The giant planet orbiting the cataclysmic binary DP Leonis". Astronomy and Astrophysics. 526: 5. arXiv:1011.3905. Bibcode:2011A&A...526A..53B. doi:10.1051/0004-6361/201015942. S2CID 119184531. A53.
- ^ a b c d Schwope, A. D.; et al. (2002). "A multiwavelength timing analysis of the eclipsing polar DP Leo". Astronomy and Astrophysics. 392 (2): 541–551. arXiv:astro-ph/0111457. Bibcode:2002A&A...392..541S. doi:10.1051/0004-6361:20011651. S2CID 17284811.
- ^ "DP Leo". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-03-25.
- ^ Qian, S.-B.; et al. (2010). "Detection of a Giant Extrasolar Planet Orbiting the Eclipsing Polar DP Leo". The Astrophysical Journal Letters. 708 (1): L66–L68. Bibcode:2010ApJ...708L..66Q. doi:10.1088/2041-8205/708/1/L66.
- ^ Biermann, P.; et al. (June 1985). "The new eclipsing magnetic binary system E 1114+182". Astrophysical Journal. 293: 303–320. Bibcode:1985ApJ...293..303B. doi:10.1086/163238.