The universe hides many mysteries, and one of them is whether it is possible to detect signs of intelligent life on other planets?
When distant planets pass in front of their stars, their atmospheres filter the light and leave behind traces of chemical compounds. JWST, which has become a kind of eye on space, can detect gases in the atmospheres of planets. But what would it look like if an alien civilization had its own version of JWST and decided to observe Earth?
Most of the Earth’s atmosphere is made up of nitrogen and oxygen, but other gases, albeit in smaller quantities, can have a significant impact on our planet.
The effects of climate change have become visible and can be observed from afar. This important discovery raises interesting questions about the nature of Earth’s atmosphere and whether aliens can recognize the signs of an intelligent civilization.
A team of astronomers conducted a study where they calculated what the features of Earth’s atmosphere would look like in infrared light.
Their analysis showed the presence of a variety of gases, including methane, carbon dioxide, ozone and even CFCs, which have been present on Earth for 33 years.
In such an off-world scenario, the presence of CFCs would be strong evidence of an artificial source as they do not occur naturally. The biosphere and the “technosphere” would be scrutinized, and extraterrestrial observers would certainly be surprised.
Despite the louder signals, the team was still able to isolate methane, carbon dioxide and ozone. However, without context, these gases don’t in themselves indicate the presence of intelligent life, but they can spark interest and raise questions.
Using Earth as a model will help astronomers better understand the atmospheric characteristics of exoplanets like ours.
An interesting test object are the TRAPPIST-1 planets: seven Earth-sized exoworlds orbiting a red dwarf. If they have an atmosphere, JWST can help determine their habitability.
Among the 4,000 planets within 50 light-years of Earth, there may already be civilizations watching us.
However, the Fermi paradox, which is why they haven’t contacted us, remains one of the most exciting questions in astronomy and the search for extraterrestrial civilizations.
