A new study about life on other planets suggests pollution may be the key in finding alien civilizations. This would be a new approach to finding extraterrestrial life by studying the atmospheres of planets.

The study was done by theorists at the Harvard Smithsonian Center for Astrophysics. It says we may be able to spot certain pollutants, under ideal conditions, in the atmosphere of far off planets. By looking for gases like oxygen and methane it could be a sign of intelligent life.

They also say looking for a planet that has high levels of pollutants could be a sign of intelligent life with the theory being if a planet was too cold, the inhabitants may have polluted the atmosphere on purpose to hold in the heat. The other thought would be that the planet wasn’t being taken care of and it could be a warning sign of dangers that the inhabitants aren’t taking care of their world.

Some pollutants in Earth’s atmosphere last up 50,000 years, so scientist hope this new approach will help in the search for life on other planets. Basically they believe if they can find pollution, they will find life.