Terraforming or geo-engineering alien
As far as we know, there is no natural process that can significantly enhance the atmosphere of a terrestrial planet in chlorofluorocarbons ( CFCs ). If we find it, it necessarily would be a technosignature. It could be, for example, the remains of a time when an alien civilization does not care about its environment. Since these two CFCs have lifetimes of about 50,000 years, they could allow the atmosphere of an exoplanet to keep the memory of the turbulent history of this civilization even after its extinction . The most likely is that CFCs were massively and deliberately released to terraform a planet that was too cold for the existence of large amounts of liquid water. It could also be a strategy adopted by the ET civilization to keep the planet habitable due to the cooling of the star host . http://enjoycoloring.com/tag/funny/
In theory, one could also find this type of technosignature for exoplanets orbiting Sun-like star, but according to three astrophysicists, this would require waiting generation telescope that will succeed the JWST.
As far as we know, there is no natural process that can significantly enhance the atmosphere of a terrestrial planet in chlorofluorocarbons ( CFCs ). If we find it, it necessarily would be a technosignature. It could be, for example, the remains of a time when an alien civilization does not care about its environment. Since these two CFCs have lifetimes of about 50,000 years, they could allow the atmosphere of an exoplanet to keep the memory of the turbulent history of this civilization even after its extinction . The most likely is that CFCs were massively and deliberately released to terraform a planet that was too cold for the existence of large amounts of liquid water. It could also be a strategy adopted by the ET civilization to keep the planet habitable due to the cooling of the star host . http://enjoycoloring.com/tag/funny/
In theory, one could also find this type of technosignature for exoplanets orbiting Sun-like star, but according to three astrophysicists, this would require waiting generation telescope that will succeed the JWST.