With the rise of cell phones, it's never been easier to get in touch.

You just unlock your phone, tap a name, and in just a few seconds, you can literally talk to someone

on the other side of the planet.

We're all used to it by now, but the technology that makes that call possible is pretty

incredible.

When you initiate that phone call, the antenna on your cell phone beams a radio signal to a nearby cell tower.

The cell tower then sends this signal over a fiber optic line to a switching center.

From there, the signal is connected to another cell tower, which then beams it to the phone

of whoever you're calling.

Hello.

That's complicated enough, but what happens when you need to talk to someone who's not even on this planet?

Houston, this Neil, radio check.

You're listening to 20,000 Hertz.

Neil, this is Houston, loud and clear.

Break, break, buzz, this is Houston.

Radio check and verify TV circuit breaker in.

When you're orbiting the Earth at over 17,000 miles an hour,

communication gets really tricky.

They use what's considered space-to-ground loops. It's radio frequency. And because they're

moving around the Earth so quickly, they have to bounce off a satellite in order for it to get

transmitted down. Alexandria Perryman is an audio engineer at the Johnson Space Center in Houston.

Yep, the same Houston that the astronauts are always talking to.

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