If you read or watch any science fiction at all, you probably know that one of the most perilous parts of any space travel is the extreme cold of deep space: As soon as an astronaut is exposed to the vacuum, they freeze solid.
But depending on where in the universe the story is taking place, that danger might be overstated.
If you're way, way out in the universe, too far from stars and galaxies to catch any light whatsoever, yes, it's mind-bogglingly cold. Scientists estimate that the coldest place in the universe might get down to minus-454 degrees Fahrenheit.
But since present-day astronauts stick close to home, light from the sun can push temperatures to 250 degrees or more. The iconic white suits astronauts wear for spacewalks reflect light, keeping them (relatively) cool.
So when you're watching a fingernail-biting spacewalk in the next big space flick, remember that your protagonist may be freezing, but actual space-walkers face an entirely different danger.
