Mu Arae d
Mu Arae d, also known as HD 160691 d, formally named Rocinante , is an extrasolar planet orbiting the star Mu Arae of the constellation Ara. Characteristics. The planet has a mass about half that of Jupiter and orbits at a distance of 0.921 AU from the star with a period of 310.55 days. The planet may be located at a distance close enough to the star to receive a comparable amount of ultraviolet radiation as the Earth does from the Sun. However, it is too close to the star to be able to support liquid water at  its surface. Furthermore, given its mass, the planet is likely to be a gas giant with no solid surface. Name. In July 2014 the International Astronomical Union launched NameExoWorlds, a process for giving proper names to certain exoplanets and their host stars. The process involved public nomination and voting for the new names. In December 2015, the IAU announced the winning name was Rocinante for this planet. The winning name was submitted by the Planetario de Pamplona, Spain. Rocinante was the horse of the lead character of the novel "El Ingenioso Hidalgo Don Quixote de la Mancha". Mu Arae d