Scientists from the University of Vienna revealed that all the planets in the TRAPPIST-1 system are probably not suitable for the existence of living organisms due to the fact that they are devoid of atmosphere as a result of the harsh radiation of the parent star. This is reported in an article published in the journal Astronomy & Astrophysics.
The researchers analyzed data from observations of the TRAPPIST-1 system and other red dwarfs, which allowed them to calculate the amount of high-energy radiation emitted by the star. They then modeled the effects of this radiation on the possible early atmospheres of the outer planets and determined their evaporation rates.
It turned out that on all worlds the atmospheres disappear quite quickly – in just a few hundred million years. If, instead of a red dwarf, the planets revolved around a yellow main-sequence star like the Sun, initially dense atmospheres would evolve into gaseous envelopes of varying thickness, as is now observed for Venus, Earth, and Mars. However, young red dwarfs emit even higher-energy radiation, so the atmospheres would evaporate even faster.
