LOOKING for alien intelligence? One way might be to keep an eye out for an exoplanet that has been messed up with chemical pollution or is spilling light into space (see 鈥淭o spot an alien, follow the pollution trail鈥�). If we do discover an alien civilisation this way, we鈥檒l know we aren鈥檛 the only dirty denizens of the galaxy. But there鈥檚 a flip side to this idea: our own pollution could reveal our presence to extraterrestrials. That provides yet another good reason why we should mend our polluting ways. What鈥檚 bad for Earth鈥檚 environment could also invite an alien invasion.
Pollution sends an interstellar message
What's bad for Earth's environment could also invite an alien invasion