NASA researchers with the help of Hubble Space Telescope have detected an atmospheric layer on a blazing-hot exoplanet that absorbs ultraviolet and visible light, acting as a kind of “sunscreen”.
This atmospheric layer includes molecules that absorb ultraviolet and visible light, acting as a kind of “sunscreen” for the planet it surrounds. Until now, scientists were uncertain whether these molecules would be found in the atmospheres of large, extremely hot planets in other star systems.
Some of these planets are so hot in their upper atmospheres, they’re essentially boiling off into space,” said Avi Mandell, a planetary scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland,
In Earth’s atmosphere, the stratosphere sits above the troposphere – the turbulent, active-weather region that reaches from the ground to the altitude where nearly all clouds top out.
In the troposphere, the temperature is warmer at the bottom – ground level – and cools down at higher altitudes. The stratosphere is just the opposite. In this layer, the temperature increases with altitude, a phenomenon called temperature inversion.
On Earth, temperature inversion occurs because ozone in the stratosphere absorbs much of the Sun’s ultraviolet radiation, preventing it from reaching the surface, protecting the biosphere, and therefore warming the stratosphere instead.
Using Hubble, the researchers have settled this debate by identifying a temperature inversion in the atmosphere of WASP-33b, which has about four-and-a-half times the mass of Jupiter.