10. Planet Osiris
HD 209458 b, located 150 light years away from planet Earth, in the Pegasus constellation, and is the first exoplanet to be discovered in transit of its orbiting star. It is 30% larger than Jupiter, while its orbit is 1/8th of Mercury distance from Sun. Naturally, its temperature is extremely high: about 1832°F. This gas planet, under the extreme heat, and immense pressure, has faced evaporation of different atmospheric gases that stream escape its gravitational field, including hydrogen, carbon and oxygen. Surprised scientists classify it in a whole new planet classification called chthonian.
