With a dayside temperature of roughly 380 kelvins (about 225 degrees Fahrenheit), TRAPPIST-1 c is now the coolest rocky exoplanet ever characterized based on thermal emission. The precision necessary for these measurements further demonstrates Webb’s utility in characterizing rocky exoplanets similar in size and temperature to those in our own solar system.
The result marks another step in determining whether planets orbiting small red dwarfs like TRAPPIST-1 – the most common type of star in the galaxy – can sustain atmospheres needed to support life as we know it.
“We want to know if rocky planets have atmospheres or not,” said Sebastian Zieba, a graduate student at the Max Planck Institute for Astronomy in Germany and first author on results being published today in Nature. “In the past, we could only really study planets with thick, hydrogen-rich atmospheres. With Webb we can finally start to search for atmospheres dominated by oxygen, nitrogen, and carbon dioxide.”
Read more at: NASA Goddard Space Flight Center
(Photo Credit: NASA, ESA, CSA, Joseph Olmsted STScI)