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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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Baku.
Baku.
Eso.
You're ready for the water.
Stand by to thrust.
Starbird, break.
Break.
Hello and welcome to Crowd Science from the BBC World Service.
I'm Caroline Steele and we're starting this episode in the South Pacific, close to the island nation of Tonga.
So the current time is exactly 8:00 in the morning local time, and we'll wait for our permission to dive.
This is marine biologist Professor Alan Jamieson.
He sat on the surface of the ocean in a submersible weighing more than 12 tonnes.
It's called Bakunawa, or Baku for short.
And Alan isn't alone.
He's with pilot Luke Ziebermeyer.