What is Planet Osiris?
Planet Osiris, officially known as HD 209458 b, is a gas giant planet orbiting a main sequence star HD 209458, located 150 light-years away in the constellation of Pegasus. The planet was discovered by spectroscopic studies on 5 November 1999, the first extrasolar planet discovered orbiting a Sun-like star, and its transit was observed shortly afterward, on 9 November 1999. This was also the first observation of an extrasolar planet transiting its home star. HD 209458 is a “Hot Jupiter” planet, with a mass 0.69 times that of Jupiter, a volume 146% greater than Jupiter, and a orbital radius of 0.045 AU (astronomical units), about an eighth of the distance between Mercury and the Sun.
