Astronomy

HD 179949 b – an Extrasolar Planet

HD 179949 b – an Extrasolar Planet

HD 179949 b is a gas giant exoplanet in the habitable zone of an F-type star. It is an extrasolar planet orbiting the star HD 179949 discovered by the Anglo-Australian Planet Search at the Anglo-Australian Observatory. It has a mass of 0.916 Jupiters, takes 3.1 days to complete one orbit around its star, and is 0.0443 AU away from it.

It was discovered in the year 2000. The planet is a “hot Jupiter,” or a Jupiter-mass planet that orbits very close to its parent star. In this case, the orbital distance from the Sun is nearly one-tenth that of Mercury. One orbital revolution lasts about three days.

Its magnetic field creates a bright spot on its star at 30 degrees latitude, which rotates at an angle of 87 degrees. If the planet orbited at an angle between 83 and 97 degrees, its transit would be visible from Earth. The angle of inclination is thus 83 degrees or less, but not much less, and its mass is constrained to 0.923±0.077. The star and the planet are not tidally locked.

The temperature would be 1533 K if the planet were perfectly grey, with no greenhouse or tidal effects, and a Bond albedo of 0.1. This, like Tau Boötis b, is hotter than the predicted temperature of HD 209458 b (1392K) and close to the temperature of HD 149026 b before measurements were taken.

Initially, searches for water in the planet’s atmosphere were inconclusive, as were attempts to determine the presence of titanium and vanadium oxides. Meanwhile, carbon monoxide and water have been detected in HD 179949b’s dayside emission.

HD 179949 b has been identified as a candidate for “near-infrared characterization using the VLTI Spectro-Imager.” As in 2021, light reflected off-planet could not be detected, implying that HD 179949 b has a low albedo.

Mastika is the name of the planet HD 179949 b. Brunei chose the name as part of the NameExoWorlds campaign to commemorate the IAU’s 100th anniversary. Mastika is a Malay word that means “gem,” “precious stone,” or “the prettiest, most beautiful.”