Astronomers have proposed chlorofluorocarbons as a sign of an alien civilization
The James Webb Space Telescope (JWST) is capable of detecting signs of activity of alien civilizations on exoplanets by atmospheric pollution. This is reported in the preprint of the article published in the arXiv repository. Briefly about the study tells the publication Universe Today.
As a potential technosignature indicating the presence of an advanced alien civilization, experts have proposed chlorofluorocarbons —CFCs) - compounds that are produced on an industrial scale as refrigerants and cleaning agents. CFCs have created the ozone hole and are powerful greenhouse gases. It is shown that these substances are capable of producing a distinct signal, noticeable when observing exoplanets using a high-resolution space telescope.
According to the authors of the work, JWST can achieve greater success if it observes stars of spectral class M, that is, red dwarfs. They are dim enough not to drown out the technosignature signals. An example of such a star is TRAPPIST-1, located 40 light-years from Earth and having several Earth-like planets. On the contrary, the sun-like stars belonging to class G are too bright to distinguish CFCs.
Despite the fact that red dwarfs produce powerful flashes capable of destroying life on exoplanets, they become calmer with age, which allows for the existence of living organisms and their evolution into intelligent life forms.
