HD 80606 and HD 80607
The HD 80606/7 binary star system on GALEX sky survey
Epoch J2000.0 Equinox J2000.0
|Right ascension||09h 22m 37.5679s|
|Declination||+50° 36′ 13.397″|
|Apparent magnitude (V)||+8.93|
|Right ascension||09h 22m 39.7266s|
|Declination||+50° 36′ 13.927″|
|Apparent magnitude (V)||+9.07|
|Spectral type||G5V / G5V|
|Radial velocity (Rv)||3.6 / 3.3 km/s|
|Proper motion (μ)||RA: 42.80 / 46.98 mas/yr
Dec.: 8.26 / 6.92 mas/yr
|Parallax (π)||9.51 / 17.13 mas|
|Age||7.63 ×109 years|
HD 80606 and HD 80607 are two stars comprising a binary star system approximately 190 light-years away in the constellation of Ursa Major. Both stars orbit each other at an average distance of 1,200 astronomical units. The binary system is listed as Σ1341 in the Struve Catalogue of Double Stars, however this designation is not in wide use and the system is usually referred to by the HD designations of its constituent stars. An extrasolar planet has been confirmed to orbit HD 80606 in a highly elliptical orbit.
Naef's team in 2001 discovered HD 80606 b. It is misaligned with the star's rotation at 53 degrees. Additional studies using the Spitzer Space Telescope in the infrared, and the Very Large Array in the millimeter radio, have shown that the highly eccentric planet 'b' orbiting HD 80606 grazes the parent star at its closest passage to produce difficult-to-detect stellar lobing, severe 'space weather', aurorae and other non-thermal activity.
At the time, its orbit was the most eccentric orbit of any extrasolar planet known. It has an eccentricity of 0.9336, comparable to that of Comet Halley in the Solar System. The eccentricity may be a result of the Kozai mechanism, which would occur if the planet's orbit is significantly inclined to that of the binary stars. This conclusion is reinforced by the detection of the misalignment, an expected result of the Kozai mechanism.
In a simulation of a 10 million year span, the planet "sweeps clean" most test particles within 1.75 AU of HD 80606. The 8:1 resonance hollows out another Kirkwood gap at 1.9 AU. There cannot be any habitable planets in this system. Also, observation has ruled out planets heavier than 0.7 Jupiter mass with a period of one year or less.
(in order from star)
|b||4.0 ± 0.3 MJ||0.453 ± 0.015||111.436 ± 0.003||0.9336 ± 0.0002||89.285 ± 0.023°||0.987 ± 0.061 RJ|
- "Exoplanets: The Hunt Continues!" (Press release). Garching, Germany: European Southern Observatory. April 4, 2001. Retrieved December 27, 2012.
- Naef, D.; et al. (2001). "HD 80606 b, a planet on an extremely elongated orbit". Astronomy and Astrophysics Letters. 375 (2): L27–L30. arXiv:. Bibcode:2001A&A...375L..27N. doi:10.1051/0004-6361:20010853.
- Moutou, C.; et al. (2009). "Photometric and spectroscopic detection of the primary transit of the 111-day-period planet HD 80606 b". Astronomy and Astrophysics Letters. 498 (1): L5–L8. arXiv:. Bibcode:2009A&A...498L...5M. doi:10.1051/0004-6361/200911954.
- Roberts, Jessica E.; et al. (2013). "MOST Space Telescope Photometry of the 2010 January Transit of Extrasolar Planet HD80606b". The Astrophysical Journal. 762 (21). 55. arXiv:. Bibcode:2013ApJ...762...55R. doi:10.1088/0004-637X/762/1/55.
- Lazio, T.J.W., Shankland, P.D., Farrell, W.M., & Blank, D.L., 2010, Astronomical Journal, 140, 1929. http://adsabs.harvard.edu/abs/2010AJ....140.1929L
- Since then, HD 20782 b has been found, at 0.97.
- Fossey, S. J.; et al. (2009). "Detection of a transit by the planetary companion of HD 80606". Monthly Notices of the Royal Astronomical Society: Letters. 396 (1): L16–L20. arXiv:. Bibcode:2009MNRAS.396L..16F. doi:10.1111/j.1745-3933.2009.00653.x.
- Wittenmyer, Robert A.; et al. (2007). "Dynamical and Observational Constraints on Additional Planets in Highly Eccentric Planetary Systems". The Astronomical Journal. 134 (3): 1276–1284. arXiv:. Bibcode:2007AJ....134.1276W. doi:10.1086/520880.
- "Distant planet's roasting orbit". BBC News. 2009-01-29. Retrieved 2009-01-29.
- HD 80606 and HD 80607 on WikiSky: DSS2, SDSS, GALEX, IRAS, Hydrogen α, X-Ray, Astrophoto, Sky Map, Articles and images