Pi Mensae b (also known as π Mensae b or HD 39091 b), is an extrasolar planet located around 59 light years away from Earth in the constellation of Mensa. The planet orbits the yellow subgiant star Pi Mensae. It was discovered in October 2001.
Detection and discovery[]
On October 15, 2001, a team of astronomers including Jones, Butler, Tinney, Marcy, Penny, McCarthy, Carter, and Pourbaix announced the discovery of one of the most massive extrasolar planets ever found. It was discovered by the Anglo-Australian Planet Search team, using a Doppler spectrometer mounted on the Anglo-Australian Telescope.
Overview[]
Pi Mensae b has a very eccentric orbit. The planet takes about 5.89 years, or 2151 days, to complete an orbit around its star. The semi-major axis of the planet is about 3.38 AU while the semi-minor axis is 2.559 AU. The planet passes through the star's habitable zone at periastron (1.21 AU). While at apastron, it passes to beyond the Jupiter-Sun distance (5.54 AU). This gravitational influence would disrupt the orbits of any Earth-like planets that may be present in the system, and might have potentially thrown them into the star, or out into the interstellar medium.
Pi Mensae b is over ten times more massive than Jupiter. The inclination of the planet is not known and it is possible that the planet may not be a gas giant but instead a brown dwarf.