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So a neutron star is kind of about the size of Chicago.
Unexpected Elements from the BBC World Service.
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Hi, I'm Alex.
Nice to meet you.
Hello and welcome to Crowd Science from the BBC World Service.
Ready?
I'm.
Yes.
I'm Alex Lethbridge and I'm in the Austrian capital of Vienna to see a small aquarium.
Sometimes we're not even convinced they're in here, but if you look around, you can find them.
Helping me here is Eli Tanake, director of the Institute of Molecular Biotechnology, Austria.
She's got a keen eye because just then, here, this one, there's the white one.
Oh, wow.
That's a.
Such an expressive face.
From under a round tree stump, a white face with beady half olive eyes is looking up at me and to either side of its face are three pink fuzzy extrusions.
They're gills which suddenly fan in and out again.
Did you see the gills?