You're listening to Shortwave from NPR.

Hey, Sherwaiver is Regina Barber here.

Recently, our producer Burley McCoy was out on a frozen lake near her home.

It's been a weird winter, so I was already kind of worried about the ice safety.

Don't worry, Burley knows about being safe on the ice.

But then she saw something that

freaked her out. There were these star-looking kind of spidery patterns in the ice. They were

black and branching, and they kind of just made me nervous because I spent a lot of time on the ice

and I hadn't seen them before, and I didn't know what they were. Lucky for Burley, she works on a science podcast.

So we called up an expert to ask about this icy phenomenon.

They're actually quite common, but you need a particular set of circumstances to happen.

Victor Sci is a geophysicist at Brown University.

He says the thing Burley was seen is called a lake star.

He studied them as a visiting graduate student at Woods Hole Oceanographic Institution.

There his advisor gave him a task.

Figure out the science behind lake stars.

Victor did by creating them in the lab.

And here's the cool thing.

The research eventually led Victor somewhere unexpected, a water world

in space. Today on the show, Lake Stars, how they're formed, and why studying them may help

us understand where the water is on Europa, one of Jupiter's largest moons. We'll also tell you,

and Burley, what Lake Stars might say about the safety of the ice.

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