'Bad radiation' for Mars missions

Some bad news for Mars mission plans - astronauts travelling to the Red Planet would get a big dose of damaging radiation.

The information's come from Nasa's Curiosity rover. It counted the number of high energy space particles striking it on its eight-month journey there.

It shows that astronauts would be exposed to radiation levels higher than current safety limits allow.

And that's before they'd even reached the planet's surface!

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