Two Columbia University astronomers, Professor David Kipping and graduate student Alex Teachey, suggest humanity could use lasers to conceal the Earth from searches by advanced extraterrestrial civilizations.

Several prominent scientists, including Stephen Hawking, have cautioned against humanity broadcasting our presence to intelligent life on other planets. Other civilizations might try to find Earth-like planets using the same techniques we do, including looking for the dip in light when a planet moves directly in front of the star it orbits. Continue reading »