If extraterrestrial intelligence exists somewhere in our galaxy, a new MIT study proposes that laser technology on Earth could, in principle, be fashioned into something of a planetary porch light—a beacon strong enough to attract attention from as far as 20,000 light years away

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If extraterrestrial intelligence exists somewhere in our galaxy, a new MIT study proposes that laser technology on Earth could, in principle, be fashioned into something of a planetary porch light—a beacon strong enough to attract attention from as far as 20,000 light years away