The oversized planet WASP-18b, located 325 light-years from Earth, is wrapped in a smothering stratosphere loaded with carbon monoxide and devoid of water, a NASA-led team has found. "We don't know of any other extrasolar planet where carbon monoxide so completely dominates the upper atmosphere," said Sheppard, lead author of the research published in the Astrophysical Journal Letters. On Earth, ozone absorbs UV in the stratosphere, protecting our world from a lot of the Sun's harmful radiation. The findings indicate that WASP-18b has hot carbon monoxide in the stratosphere and cooler carbon monoxide in the layer of the atmosphere below, called the troposphere. The team determined this by detecting two types of carbon monoxide signatures, an absorption signature at a wavelength of about 1.6 micrometres and an emission signature at about 4.5 micrometres.

Source: dna November 30, 2017 11:15 UTC