(Credit: NASA) We’ve been looking up at the stars for centuries, but it’s only in the last few decades that we’ve been able to actually think about exploring them. Space is still one of the harshest environments that we’ve ever discovered — colder than most people can imagine, with no oxygen and plenty of radiation to increase the risk of cancer and other dangerous diseases. When an emergency happens in space, there’s no one to come to the rescue. So how do astronauts handle it?