NASA chief scientist Ellen Stofan believes we 're close to finding alien life . Indications within a decade ; definitive evidence within `` 20 to 30 years , '' she said . The first step in the search for extraterrestrial intelligence is identifying what kind of signal it sends out and how much energy it uses up.
NASA chief scientist Ellen Stofan believes we 're close to finding alien life . Indications within a decade ; definitive evidence within `` 20 to 30 years , '' she said . Finding water on other celestial bodies is key to determination .