Credit: Illustration: NASA, ESA, and G. Bacon (STScI);
Science: NASA, ESA, and T. Evans (University of Exeter)
ARTIST'S CONCEPT OF EXOPLANET WITH GLOWING WATER ATMOSPHERE.
This is an artist's impression of the gas giant exoplanet WASP-121b. The bloated
planet is so close to its star that the tidal pull of the star stretches it into an egg shape. The top of the planet's atmosphere is heated to a blazing 4,600 degrees Fahrenheit (2,500 degrees Celsius), hot enough to boil iron. This is the first planet outside our solar system where astronomers have found the strongest evidence yet for a stratosphere -- a layer of atmosphere in which temperature increases with higher altitudes. The planet is about 900 light-years away.