It's decently likely that, sometime in the future, a major solar storm will hit Earth, wreaking havoc on our infrastructure and crippling our satellites. But there's a more long-term danger: space could become too dangerously radioactive to stay there.
And some new research indicates that we could face a situation that keeps us from exploring space, within our lifetimes.
While we haven't sent humans beyond low-Earth orbit in close to forty years, we've carved out quite a niche for ourselves in the area of space directly around our planet. The International Space Station provides a constant human presence in space, and we've built up a massive network of satellites that are crucial to our communications infrastructure, not to mention navigation, scientific research, weather monitoring, and a bunch of other things.
What allows us to keep humans and all that sensitive electronics up there is the presence of huge clouds of plasma, which extend out to a few times Earth's radius and provide a buffer zone against cosmic radiation. Without this protective cloud, electromagnetic waves could form, which would send deadly radiation bursts into the space above Earth.
The problem is that this cloud can be destroyed if a big enough solar storm hits it. Recent Sun activity in October 2003 caused the cloud to contract to just two times the Earth's radius, and scientists believe that a huge solar outburst in 1859 completely destroyed the protective layer. Of course, there weren't nearly as many communications satellites up in space in the mid-19th century, so that didn't have nearly as big an impact as the destruction of the cloud would if it happened today.
According to new research from UCLA, a big enough solar storm would form a belt of dangerous radiation right on the edge of low-Earth orbit. This would place astronauts and satellites alike at the mercy of electromagnetic waves and dangerous radiation. The researchers calculate that this belt would persist for at least a decade before the plasma cloud began to reassert itself.
In that time, the belt would drastically reduce the lifespan of satellites. It's an open question whether it would be safe for astronauts to remain in the International Space Station - the answer probably depends on the level of severity of the solar storm. It might also pose some complications for any planned missions beyond low-Earth orbit. Admittedly, that's not something we have to worry about right now, but hey...the solar blast could happen in the 2040s, by which time we might just be ready to return to the Moon or something.
Anyway, lead researcher Yuri Shprits suggests that installing thicker shielding around satellite electronics could stave off some of the problem. But the fact is, space really is a dangerous, inhospitable place, and for all the challenges and occasional tragedies we've endured while exploring it, so far space has been pretty easy on us. One big solar storm could change that for the foreseeable future.