Discovery | |
---|---|
Discovered by | Currie et al. [1] |
Discovery site | Keck Telescope, Very Large Telescope, Subaru Telescope |
Discovery date | October 17, 2013 |
Direct imaging | |
Orbital characteristics | |
1968.3 [2] | |
Star | ROXs 42B |
Physical characteristics | |
Mean radius | 2.43±0.18 –2.55±0.2 [3] RJ |
Mass | 9.0+6 −3 [3] MJ |
3.8 ± 0.2 [3] g | |
Temperature | 1,800-2,600 K [3] |
ROXs 42Bb is a directly imaged planetary-mass companion [1] to the binary M star ROXs 42B, [4] a likely member of the Rho Ophiuchi cloud complex. The companion was announced/discovered on October 17, 2013, by University of Toronto astronomer Thayne Currie.
The object has an estimated mass around 9 Jupiter masses, depending on the age of the star, [1] similar to the masses of directly imaged planets around HR 8799 and beta Pictoris. However, it is unclear whether ROXs 42Bb formed like these planets via core accretion, by disk (gravitational) instability, or more like a binary star. Preliminary fits of the spectra and broadband photometry to atmospheric models imply a radius of 2.43 ± 0.18 RJ for an effective temperature of about 2,000 K or a radius of 2.55 ± 0.20 RJ for about 1950 K. [3] Like Beta Pictoris b, ROXs 42Bb's atmosphere is likely very cloudy and dusty. [3]
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This page describes exoplanet orbital and physical parameters.
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HD 106906 b is a directly imaged planetary-mass companion and candidate exoplanet orbiting the star HD 106906, in the constellation Crux at about 336 ± 13 light-years (103 ± 4 pc) from Earth. It is estimated to be about eleven times the mass of Jupiter and is located about 738 AU away from its host star. HD 106906 b is an oddity; while its mass estimate is nominally consistent with identifying it as an exoplanet, it appears at a much wider separation from its parent star than thought possible for in-situ formation from a protoplanetary disk.
51 Eridani is a star in the constellation Eridanus. It has an apparent magnitude of 5.22, meaning it is just visible to the unaided eye in suburban and rural skies. The primary star's absolute magnitude is 2.87. There is also a binary star named GJ 3305 which shares the same proper motion through space with it, making it overall a triple star system.
Beta Pictoris c is the second exoplanet discovered orbiting the young star Beta Pictoris, located approximately 63 light-years away from Earth in the constellation of Pictor. Its mass is around nine times that of Jupiter, and it orbits at around 2.7 astronomical units (AU) from Beta Pictoris, about 3.5 times closer to its parent star than Beta Pictoris b. It has an orbital period of 1,200 days. The orbit of Beta Pictoris c is moderately eccentric, with an eccentricity of 0.24.
ROXs 12 is a binary system of pre-main-sequence stars. It belongs to the Rho Ophiuchi cloud complex. The surface temperature of the primary star is 3900±100 K. ROXs 12 is much younger than the Sun with an age of 7.6+4.1
−2.5 million years.