Scientists from the Harvard-Smithsonian Centre for Astrophysics propose that a 10-year old massive radio wave could be from a faraway alien civilization using artificial beams to power spaceships with light sails...

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Scientists from the Harvard-Smithsonian Centre for Astrophysics propose that a 10-year old massive radio wave could be from a faraway alien civilization using artificial beams to power spaceships with light sails...