A search of more than 1,300 galaxies for extraterrestrial signals has helped to constrain expectations as to how many communicating, technological civilizations may exist beyond Earth. Conducted with ...

Although no aliens were found, the results have helped constrain expectations of possible alien transmitter power. When you purchase through links on our site, we may earn an affiliate commission.

It's quick and easy to access Live Science Plus, simply enter your email below. We'll send you a confirmation and sign you up for our daily newsletter, keeping you up ...