Space debris to go critical, reduce all satellites to junk?

The amount of debris in the orbits used by our communications and weather satellites is building toward critical mass, a point of no return in which debris starts to smash into active satellites, turning them into more debris that smashes more sats, and so on. There's no cost-effective solution to the space-junk problem and none are on the horizon. Marshall Kaplan (Johns Hopkins Space Department) believes that it's inevitable that all the satellites in use will be percussively decommissioned and their orbits will be unusable. He speculates that we'll replace them with lower orbit satellite constellations that relay to one another in order to achieve the coverage attained by today's high-orbit sats. Here's Gen. William Shelton, commander of USAF Space Command:

"The traffic is increasing. We've now got over 50 nations that are participants in the space environment," Shelton said last month during the Space Foundation's 27th National Space Symposium. Given existing space situational awareness capabilities, over 20,000 objects are now tracked.

"We catalog those routinely and keep track of them. That number is projected to triple by 2030, and much of that is improved sensors, but some of that is increased traffic," Shelton said. "Then if you think about it, there are probably 10 times more objects in space than we're able to track with our sensor capability today. Those objects are untrackable ... yet they are lethal to our space systems -- to military space systems, civil space systems, commercial -- no one's immune from the threats that are on orbit today, just due to the traffic in space."

Ugly Truth of Space Junk: Orbital Debris Problem to Triple by 2030

(via /.)