British astronaut Tim PeakeReuters

British astronaut Tim Peake, back from a six-month mission aboard the International Space Station, said at a news conference Tuesday in Germany that he’d return to space “in a heartbeat,” and urged his country to conduct more space missions.

Peake was the first British astronaut to go to space since 1991. He will now spend three weeks rehabilitating at the European Astronaut Center in Cologne, Germany. There, doctors will monitor his health as he readjusts to life with gravity. As my colleague, Marina Koren, wrote in March, weightlessness can take its toll on humans:

In weightlessness, the fluids in the human body float upward and clog the sinuses, making astronauts’ heads feel congested and their faces appear puffy. Their skeletons become useless; bones don’t need to support muscles in microgravity, so they start losing minerals and regenerating cells at a slower pace. Astronauts can lose 1 percent of their bone density a month. Back on Earth, it takes a year for aging men and women to lose the same amount of bone mass. In a environment that requires little strength to move around and work, muscles atrophy, their fibers shrinking.

Shortly after his return, Peake said the effects of returning to Earth felt like the “world’s worst hangover.” By Tuesday, he said he already felt much better, as The Telegraph reported:

“I’m feeing a lot better than I did on Saturday lunchtime,that’s for sure” he told reporters at the European Space Agency in Cologne, Germany,

“What’s amazing is how quickly the human body adapts to a new environment. I had the same experience when I went up into space and was amazed after just 24 hours, living on board the space station how quickly I was able to function.

“It’s a bit slower coming the other way, I can tell you, and it’s a bit harder.”

While at the space station, Peake participated in hundreds of experiments, many of which focused on the effects of weightlessness on the human body. These tests aim to give scientists a better understanding of how astronauts might endure long-term space travel, like a mission to Mars would require.  

Peake returned to earth in a Soyuz TMA-19M spacecraft, which reached 17,000 mph as it descended, slowed as it entered Earth’s atmosphere, then deployed a parachute and retro rockets that reduced its speed to 3 mph as it touched down.

Peake said he hopes the United Kingdom will send other astronauts into space.

“We have to be,” he said, “continuing our contributions to human spaceflight.”

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