James Hollopeter of GIT Satellite has a plan for getting rid of orbiting junk. He wants to launch rocket-loads of water into space to create a liquid wall for debris to slam into, so the pieces can slow down and eventually drop out of orbit.
Launched on ballistic flight paths that quickly re-enter the atmosphere, the water wouldn't add to the debris problem, unlike some other proposals to clean up space. The Defense Advanced Research Projects Agency known as DARPA wants to hear about them all.
The agency last week issued a request for ideas to clean up orbital debris, a problem that has skyrocketed since China intentionally blew up a defunct satellite as part of a weapons test in 2007 and the orbital collision of two communications spacecraft earlier this year.
"Since January 2007, we have experienced a nearly 50 percent increase in the number of cataloged debris objects," DARPA wrote in its solicitation.
The government's Space Surveillance Network currently tracks more than 20,000 objects in orbit around Earth, 94 percent of which are classified as debris. And those are just the pieces big enough to track. There are estimated to be hundreds of thousands of objects smaller than about 10 centimeters across that literally slip beneath the radar.
While hurling water into space is a decidedly low-tech affair, Hollopeter says that is one of its advantages.
"In less than 18 months, I could do a demonstration mission," he told Discovery News. "The pacing item would be getting the paperwork approval through NASA."
The so-called Ballistic Orbital Removal System could be operated inexpensively by launching water on decommissioned missiles out of suborbital launch complexes, such as NASA's Wallops Island in Virginia, he added.
The DARPA solicitation so far has attracted interest from 11 firms, including prime aerospace contractor Boeing, NASA's Space Science and Technology Center at Marshall Space Flight Center in Alabama, and several small firms.
"The debris is becoming more pronounced and more important," said B.J. Austin, president of Indiana-based In Space. "In order to preserve space for future generations, we need to mitigate debris."
Proposals are due by Wednesday.
DARPA, which does not plan on awarding a contract at this time, declined to be interviewed.
"We need more time to gather information to see what direction this study points us in before we're ready to engage in further discussions," an agency spokesman said.