You're listening to shortwave from NPR.

Emily Quang, have I got a question for you?

You always do, John Brunfield.

What is your question?

Have you ever thought about how aliens might phone us

and then like how we might be able to pick up that call?

I think since the days of ET, I pretty much went through a stint

where I only ate Reese's pieces

and the hope that something would happen.

Hey, she was just so cute.

Well, it turns out there's a very small group of scientists

who have dedicated their entire careers

to thinking about this specific problem.

And one of them is Sophia Shake.

She sums up the challenge this way.

How in the world can we use our technology on this pale blue dot

to detect someone else's technology?

I didn't realize there were scientists that did this.

Yeah, yeah.

You know, a lot of times it's just a thought experiment,

but a couple of years ago, Shake's group picked something up.

A signal that seemed like it bore a lot of the telltale

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