An exoplanet discovered in 1999 finally sees its secrets revealed. The telescope makes the discovery that we have been waiting for a long time. Trappist-1b is therefore habitable like the Earth or not?
A major discovery and a clear answer
On paper, the exoplanet Trappist-1b is perfect to host life: a correct size, rocky type, with a mass and density similar to Earth and the presence of water is possible. On top of that, it is not so far away, at 40 light years.
It was therefore one of the objectives of the James-Webb telescope: to observe the planetary system around the star Trappist-1. Composed of 7 planets, they orbit a red dwarf star. This makes Trappist-1b (planet B of the system) the closest to the star. But the weak irradiation of this one makes it a potentially habitable planet.
After probing the planet with the MIRI instrument and using a technique called secondary eclipse photometry, James-Webb managed to get an answer to the essential question: does Trappist-1b have an atmosphere?
The answer is unfortunately no… And ESA explains in a release:
The results are almost perfectly consistent with a black body made of bare rock and without an atmosphere to circulate heat. We also saw no evidence of light absorbed by carbon dioxide, which would be apparent in these measurements.
Even without an atmosphere, is there any hope?
Again it’s disappointing, but this planet is a perfectly uninhabitable rock. The analyses showed a surface temperature of about 230 degrees. But beyond the disappointment of the result, to have this kind of data is absolutely incredible. The co-author of the article, Pierre-Olivier Langage explains the positive in this discovery:
There was one target I was dreaming of having and this was it. This is the first time we can detect the emission from a rocky and temperate planet. This is a very important step in the history of the discovery of exoplanets
For scientists, beyond the result, it is an incredible exploration lab. It allows us to learn more about the formation of planets and thus discover a little more about the Universe, but also our own Earth.
There is still one last hope, because scientists are waiting to have the complete data of the phase curve to see if the changes in brightness between the illuminated and unilluminated side of the planet can make the results vary. This will allow to see a difference between the night and day temperatures in order to confirm or deny the presence of an atmosphere.