保护地球免受太空陨石的侵害

Do you want to find a meteorite? Well, here is where to look – out on the Antarctic ice. The pristine white surface makes meteorites easier to see.

你想找一颗陨石吗？你可以在南极的冰面上试试！这里一尘不染的白色表面让陨石更容易被看到。

Alexander Gerst is part of a team hunting for rocks from space, which makes sense because he has spent a lot of his time up here.

He is a former commander of the International Space Station and has spent more time in orbit than any other European. But he is back on Earth searching for clues about the origin of our Solar System.

His boss on the ice gives me a lesson in how to find a meteorite.

So John has found more meteorites than anyone else. So we're going to simulate finding a meteorite – we've placed one on the snow over there, right? So we've been driving on the Ski-Doo. We've spotted it over there. What happens next?

Well, the next thing we'll do is walk over to confirm whether it is a meteorite or not.

So you're not allowed to touch it, are you?

You don't want to touch it – and we're upwind of it too – I don't want to drip my nose on it!

No, snot is the least of it. There are strict rules to ensure nothing contaminates the meteorites.

Most meteorites date back billions of years, right to the birth of the Solar System, so the research here helps us understand how the Earth itself was formed and it could also protect our planet.

Everybody knows that the dinosaurs came to extinction because of the big, big asteroid crashing into Earth and that was long ago but nowadays, still we have asteroids hitting Earth. Sooner or later, a bigger one is going to hit us. They're made of, in principle, the same stuff as some of these rocks that we find out there on the Polar plateau. If ever one comes straight at us and we realise that – well, we can only do something about that if we know exactly what it's made of.

For astronaut Alex, the rocks hold a personal significance.

You see things coming from outer space, zipping past you into the Earth's atmosphere and that's the weird thought when you, for the first time in your life, see a shooting star from above realising, hey, that thing just flew past me.

So his Antarctic trip kind of closes a circle. The astronaut has recovered the remains of shooting stars on Earth so we can understand our planet a bit better.