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RE: QS Virginis
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A team of Chinese astronomers have discovered a giant planet close to the exotic binary star system QS Virginis. The planet is currently dormant.
According to Professor Shengbang Qian of National Astronomical Observatories of Yunnan Observatory, there is high possibility that the two stars will one day erupt in a violent nova outburst, as reported by the Royal Astronomical Society.

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QS Virginis b
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QS Virginis b is a circumbinary planet which orbits both the white dwarf and red dwarf stars in the QS Virginis system, located approximately 156 light years away in the constellation Virgo. This planet has at least 6.4 times the mass of Jupiter and takes 7.86 years to orbit the star at a semimajor axis of 4.2 AU.
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NameQS Vir b
Discovered in2009
Mass6.4 MJ
Semi major axis4.2 AU
Orbital period2869 days

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Chinese astronomers at the Yunnan Observatory have discovered a Jupiter sized exoplanet orbiting the eclipsing binary QS Virginis.
The QS Virginis binary star system consist of a cool red dwarf and a hot  white dwarf. The two stars orbit about each other only 840000 km apart (twice the distance from the Earth to the Moon); with an  orbital period of  3 hours, 37 minutes.
QS Virginis lies about 157 light years away in the constellation of Virgo.


Title: A giant planet in orbit around a magnetic-braking hibernating cataclysmic variable
Authors: S.-B. Qian, W.-P. Liao, L.-Y. Zhu, Z.-B. Dai, L. Liu, J.-J. He, E.-G. Zhao3 and L.-J. Li

Detections of Jupiter-like giant planets in orbit around short-period white dwarf binaries should provide insight into the formation and evolution of circumbinary planets (planets orbiting both components of short-period binaries), as well as into the ultimate fate of planets and the late evolutionary stage of binary stars (e.g. the evolution of the common envelope). However, to date no planets have been detected as companions to such close binaries. Here, we report the discovery of a giant planet orbiting the only known hibernating cataclysmic variable (CV), QS Vir, with a period of 7.86 yr. We analysed the variations of the orbital period of the eclipsing white dwarf-red dwarf binary, and a very small-amplitude cyclic change is found to be superimposed on a long-term period decrease. The period oscillation has the smallest amplitude among close binary stars and can be plausibly interpreted as the light-travel time effect via the presence of a third body. We found that the tertiary component is a giant planet with a mass of  ~6.4 Jupiter masses at a distance of ~4.2 astronomical units (au) from the binary. The continuous decrease is explained as angular momentum loss via magnetic braking which is driving the evolution of the hibernating CV into a normal cataclysmic binary.

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QSVirginisb.jpg
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This planet has at least 6.4 times the mass of Jupiter and takes 7.86 years to orbit the star at a semimajor axis of 4.2 AU. However unlike most other known exoplanets, its eccentricity is not known, but it is typical that its inclination is not known. This planet was detected by variable star timing on November 13, 2009.
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Position(2000): RA 13h 49m 51.9503s, Dec -13° 13' 37.482"

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Title: Activity on the M star of QS Vir
Authors: T. Ribeiro, S. Kafka, R. Baptista, C. Tappert

We report analysis of VRIJH photometry, and phase-resolved optical spectroscopy of the eclipsing DA white dwarf plus dMe dwarf binary QS Vir. Modelling of the photometric data yields an inclination of i = 74.9 ±0.6 and a mass ratio of q = M_2/M_1 = 0.50 ±0.05. Our Doppler maps indicate the presence of material in the Roche lobe of the white dwarf, at a location near the M star, likely due to accretion from the stellar wind of the M star (as opposed to Roche-lobe overflow accretion). We also constructed images of the brightness distribution of the M star at different epochs which reveal the location of two stable active regions. Doppler tomography shows that the majority of the Hydrogen and Ca II H&K emission originates on the active M dwarf, likely distributed in two preferred activity longitudes, similar to active regions on BY Dra and FK Comae systems.

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