It’s quiet out there. We’ve been listening for radio signals from other civilizations off and on for decades. But we haven’t heard a peep.

Many scientists say there’s no reason to think Earth is the only planet with life in the Milky Way Galaxy. In fact, life could be common. And if there’s life, there’s a decent chance there’s intelligent life.

Many stars are much older than the Sun, so it’s possible that there are civilizations that are much older than our own. And if they were at all interested in exploring space, they could have colonized the entire galaxy in a few million years. So if anyone is out there, the reasoning goes, we shouldn’t have much trouble finding some evidence — a radio signal, a laser beam, an artifact, or something else.

There are many possible explanations for “the Great Silence.” It could be that civilizations are so far advanced that we don’t recognize them. Or perhaps Earth is off-limits — protected by the equivalent of Star Trek’s “prime directive.” Or perhaps we haven’t looked in the right places, with the right technology.

Some have suggested that we beam invitations to make contact out into the galaxy and see if anyone responds. Others say that such a move is risky — meetings between disparate civilizations never end well.

Perhaps, though, it’s all a moot point. One other possibility is that no one else is out there — that we’re the only technological civilization in the entire galaxy.

Script by Damond Benningfield

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