Officials say that the crash this week between a U.S. commercial communications satellite and a defunct Russian satellite generated possibly thousands of pieces of debris that will hang around in low-Earth orbit for years. Vladimir Solovyov, chief of the Russian segment of the International Space Station (ISS), told reporters today that "debris from the collision could stay in orbit for up to 10,000 years, and even tiny fragments threaten spacecraft, because both travel at such a high orbiting speed." But Nicholas Johnson, NASA's chief scientist for space debris, says that's not correct. "Most of the debris will be down in decades, some perhaps as long as 100 or more years," Johnson says. He adds that NASA is waiting on military orbit monitors to assess the scene before making an estimated debris count.

"800 kilometers [500 miles] is a very popular orbit for remote Earth sensing and telecommunications satellites," Solovyov said. "The cloud [of debris] from the collision is a serious threat to them."

NASA has not revised its assessment, made immediately following the incident, that the debris clouds pose no significant risk to manned space operations, specifically the ISS and space shuttle Discovery, targeted for a launch later this month.

But some in the space community are using the collision as an opportunity to call for the development of systems to prevent such accidents from happening in the future. At present, space is a free-for-all with no rules of the road. "The collision offers a literally heaven-sent opportunity for the Obama administration to take forceful, visible and long-overdue measures to address a long-ignored issue of 'space debris,'" space consultant James Oberg told the AP.

Schematic showing all the trackable objects in low-Earth orbit before Tuesday's collision courtesy of NASA