Which animal can survive in space?

Tardigrades are microscopic animals, usually under a millimetre long, famous for surviving conditions that would kill almost anything else. In a 2007 experiment some tardigrades were exposed to the open vacuum of space and intense solar radiation while in orbit, and a number of them survived and even reproduced afterwards. They endure by entering a dried-out, dormant state called cryptobiosis, in which their metabolism nearly stops. In this state they can withstand extreme cold, heat, pressure, and dehydration. They are found all over Earth, from mountain tops to deep sea, wherever there is a film of water.