Low Earth orbit just got a free spring-clean, thanks to the sun. It turns out that increased solar activity in recent years has removed some of the satellite debris that clogs this regionMovie Camera, making it temporarily safer for other satellites and astronauts.

The United States Department of Defense is looking for ways to repurpose space junk thousands of miles above Earth back into valuable satellite parts, or even completely new spacecraft.

There is so much junk in space that collisions could start to increase exponentially, leading to a continuously growing pile of rubble in orbit, a new report warns. But while the dangers posed by growing orbital detritus are increasing, NASA's budget and management structure has not kept pace, the new report found.

Two new studies propose potential spacecraft missions that would collide with asteroids in an attempt to deflect them away from our planet. Such missions, some researchers say, may be among our best hopes to ward off asteroids that may pose a threat to Earth.

The buildup of space debris orbiting the Earth, which poses a threat to spacecraft and the environment, has reached a critical point, scientists say.

Dealing with the decades of detritus from using outer space -- human-made orbital debris -- is a global concern, but some experts are now questioning the feasibility of the wide range of "solutions" sketched out to grapple with high-speed space litter, arguing that it may be too late.

Researchers have suggested using ground-based lasers to nudge small pieces of space junk away from satellites to prevent collisions.

Until now, satellites orbiting around Earth have been limited by how much fuel they carry onboard but two satellite companies have announced a new deal to launch the first spacecraft designed to refuel other satellites in orbit. This will help reduce the problem of dead satellites sometimes languishing in space as uncontrollable debris that then poses the risk of colliding with other spacecraft.

NASA researchers are working on ground-based lasers that could be used to nudge debris in orbit, which could help move dangerous space junk away from satellites and spacecraft. They caution that this operation should be multilateral because of obvious concerns over how the laser could be used for space warfare.

Russia has begun some ambitious space projects, including a new system to protect spacecraft from space junk and a nuclear-powered engine for future spaceships, according to Russian news reports.