NN Serpentis
Encyclopedia
NN Serpentis is an eclipsing binary system approximately 1670 light-year
s away, likely a cataclysmic variable star. The system comprises an eclipsing white dwarf
star and red dwarf
star. The two stars orbit each other every 0.13 days.
In late 2009 Qian et al. announced possible discovery of a planetary companion around the cataclysmic variable. They have estimated a minimum mass of 10.7 Jupiter
masses and orbital period of 7.56 years, probably located at 3.29 Astronomical Unit
s. This has since been disproven by further measurements of the eclipse times of the binary stars.
In late 2009 and 2010 two gas giant
planets were found orbiting the recently formed post-common envelope binary NN Serpentis by a research team from the UK (University of Warwick and the University of Sheffield), Germany (Georg-August-Universitat in Göttingen, Eberhard-Karls-Universitat in Tübingen), Chile (Universidad de Valparaíso), and the United States (University of Texas at Austin).
The researchers used the fact that Earth sits in the same plane as the NN Serpentis binary star system, so we can see the larger red dwarf eclipse the white dwarf every 3 hours and 7 minutes. The astronomers were able to used these frequent eclipses to spot a pattern of small but significant irregularities in the orbit of stars and demonstrated that the pattern was due to the presence and gravitational influence of two massive gas giant planets. The more massive gas giant is about 6 times the mass of Jupiter and orbits the binary star every 15.5 years, the other orbits every 7.75 years and is about 1.6 times the mass of Jupiter.
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...
s away, likely a cataclysmic variable star. The system comprises an eclipsing white dwarf
White dwarf
A white dwarf, also called a degenerate dwarf, is a small star composed mostly of electron-degenerate matter. They are very dense; a white dwarf's mass is comparable to that of the Sun and its volume is comparable to that of the Earth. Its faint luminosity comes from the emission of stored...
star and red dwarf
Red dwarf
According to the Hertzsprung-Russell diagram, a red dwarf star is a small and relatively cool star, of the main sequence, either late K or M spectral type....
star. The two stars orbit each other every 0.13 days.
Planetary system
Chen (2009) inferred the presence of a tertiary companion orbiting the cataclysmic variable, hinted by orbital period changes, suggesting a putative orbital period spanning between 30 and 285 years and a minimum mass between 0.0043 and 0.18 Solar masses.In late 2009 Qian et al. announced possible discovery of a planetary companion around the cataclysmic variable. They have estimated a minimum mass of 10.7 Jupiter
Jupiter
Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined. Jupiter is classified as a gas giant along with Saturn,...
masses and orbital period of 7.56 years, probably located at 3.29 Astronomical Unit
Astronomical unit
An astronomical unit is a unit of length equal to about or approximately the mean Earth–Sun distance....
s. This has since been disproven by further measurements of the eclipse times of the binary stars.
In late 2009 and 2010 two gas giant
Gas giant
A gas giant is a large planet that is not primarily composed of rock or other solid matter. There are four gas giants in the Solar System: Jupiter, Saturn, Uranus, and Neptune...
planets were found orbiting the recently formed post-common envelope binary NN Serpentis by a research team from the UK (University of Warwick and the University of Sheffield), Germany (Georg-August-Universitat in Göttingen, Eberhard-Karls-Universitat in Tübingen), Chile (Universidad de Valparaíso), and the United States (University of Texas at Austin).
The researchers used the fact that Earth sits in the same plane as the NN Serpentis binary star system, so we can see the larger red dwarf eclipse the white dwarf every 3 hours and 7 minutes. The astronomers were able to used these frequent eclipses to spot a pattern of small but significant irregularities in the orbit of stars and demonstrated that the pattern was due to the presence and gravitational influence of two massive gas giant planets. The more massive gas giant is about 6 times the mass of Jupiter and orbits the binary star every 15.5 years, the other orbits every 7.75 years and is about 1.6 times the mass of Jupiter.
External links
- http://exoplanet.eu/star.php?st=NN+Ser+%28ab%29
- UK Astronomers Help Find Snooker Star System
See also
- Algol
- HW VirginisHW VirginisHW Virginis, abbreviated HW Vir, is an eclipsing binary system approximately 590 light-years away in the constellation of Virgo. The system comprises an eclipsing B-type subdwarf star and red dwarf star...
- CM DraconisCM DraconisCM Draconis is an eclipsing binary system approximately 47 light-years away in the constellation of Draco . The system consists of two nearly identical red dwarf stars located in the constellation Draco. The two stars orbit each other with a period of 1.27 days with a separation of 2.7 million...
- Kepler-16Kepler-16Kepler-16 is a binary star system in the constellation of Cygnus that was targeted by the Kepler spacecraft. Both stars are smaller than the Sun; the primary, Kepler-16A, is a class K red dwarf, and the secondary, Kepler-16B, is a class M red dwarf...