WISE J2209+2711 (WISE J220905.73+271143.9) is a

brown dwarf Brown dwarfs are substellar objects that have more mass than the biggest gas giant planets, but less than the least massive main sequence, main-sequence stars. Their mass is approximately 13 to 80 Jupiter mass, times that of Jupiter ()not big en ...

of spectral type Y0:, located in constellation

Pegasus Pegasus (; ) is a winged horse in Greek mythology, usually depicted as a white stallion. He was sired by Poseidon, in his role as horse-god, and foaled by the Gorgon Medusa. Pegasus was the brother of Chrysaor, both born from Medusa's blood w ...

at 22

light-year A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by the International Astr ...

s from Earth. Its discovery was published in 2014 by Cushing ''et al.''

Physical properties

WISE J2209+2711 is one of a few Y-dwarfs observed with JWST

NIRSpec The NIRSpec (Near-Infrared Spectrograph) is one of the four scientific instruments flown on the James Webb Space Telescope (JWST). The JWST is the follow-on mission to the Hubble Space Telescope (HST) and is developed to receive more information ...

and

MIRI Miri () is a coastal city in north-eastern Sarawak, Malaysia, located near the border of Brunei, on the island of Borneo. The city covers an area of , located northeast of Kuching and southwest of Kota Kinabalu. Miri is the second largest ...

. The modelling re-produced the spectrum with an excellent fit using

phosphine Phosphine (IUPAC name: phosphane) is a colorless, flammable, highly toxic compound with the chemical formula , classed as a pnictogen hydride. Pure phosphine is odorless, but technical grade samples have a highly unpleasant odor like rotting ...

-free and diabatic models. The excellent fit was achieved with a model that used an

effective temperature The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...

of 350 K and a

surface gravity The surface gravity, ''g'', of an astronomical object is the gravitational acceleration experienced at its surface at the equator, including the effects of rotation. The surface gravity may be thought of as the acceleration due to gravity experi ...

of 4.0. This corresponds to a 5 object with an age of 800 Myrs.

References

Pegasus (constellation) Y-type brown dwarfs WISE objects {{Brown-dwarf-stub

Physical properties

See also

References