ROXs 42Bb is a directly imaged

planet A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...

ary-mass companion to the binary M star ROXs 42B, a likely member of the

Rho Ophiuchi cloud complex The Rho Ophiuchi cloud complex is a complex of interstellar clouds with different nebulae, particularly dark nebulae which is centered 1° south of the star ρ Ophiuchi, which it among others extends to, of the constellation Ophiuchus. At an es ...

. The companion was announced/discovered on October 17, 2013 by

University of Toronto The University of Toronto (UToronto or U of T) is a public university, public research university in Toronto, Ontario, Canada, located on the grounds that surround Queen's Park (Toronto), Queen's Park. It was founded by royal charter in 1827 ...

astronomer

Thayne Currie Thayne is a town in Lincoln County, Wyoming, United States. The population was 366 at the 2010 census. Geography Thayne is located at (42.919754, –111.000714), at 5906 feet in elevation. It sits in the northern portion of Wyoming's grassy Sta ...

. The object has an estimated mass around 9 Jupiter masses, depending on the age of the star, similar to the masses of directly imaged planets around

HR 8799 HR 8799 is a roughly 30 million-year-old main-sequence star located away from Earth in the constellation of Pegasus. It has roughly 1.5 times the Sun's mass and 4.9 times its luminosity. It is part of a system that also ...

and beta Pictoris. However, it is unclear whether ROXs 42Bb formed like these planets via core accretion, formed by disk (gravitational) instability, or formed more like a binary star. Preliminary fits of the spectra and broadband photometry to atmospheric models imply an effective temperature of about 2,000 K for a radius of or about 2150 K for a radius of . Like

Beta Pictoris b Beta Pictoris b (abbreviated as β Pic b) is an exoplanet orbiting the young debris disk A-type main sequence star Beta Pictoris located approximately 63 light-years (19.4 parsecs, or km) away from Earth in the constellation of Pictor. It has ...

, ROXs 42Bb's atmosphere is likely very cloudy and dusty.

References

{{2013 in space Exoplanets discovered in 2013 Exoplanets detected by direct imaging Circumbinary planets

See also

References