— For anyone concerned about orbital debris, the February collision of two communications satellites high above
underscored the need to start mulling over ways to mitigate man-made space clutter.
The Laurel, Md.-based Johns Hopkins University Applied Physics Laboratory (APL) is taking the initiative to formulate an action plan for reducing orbital debris. A workshop is tentatively planned for later this year. Marshall Kaplan, an APL senior scientist, said the lab would like to take a leadership role in space debris reduction research through analysis, simulations and experimentation.
“It is not our mission or intent to carry out any major debris reduction programs. That is for government and industry to do,” Kaplan said. “Ideally, we want to create a
in Debris Reduction Research that will be creative and innovative in finding solutions for potential future space access issues related to space debris.”
The NASA Advisory Council endorsed studying the possibility of active debris removal during its April 16 meeting in
. The council agreed to recommend that NASA begin comparing costs of “operating in the ever-expanding debris population” versus the cost and benefits of selectively remove large objects with a high potential of fragmenting into hundreds of pieces.
To date, national and international agencies and nongovernmental groups have concentrated on steps to help lessen new debris production and better anticipate close-approaches and collisions, Kaplan said in an April 1 interview with Space News during the 25th National Space Symposium here.
“Nobody has taken a serious look at actual reduction of existing debris. This is where the crux of the problem is,” Kaplan said. “What’s up there now is sufficiently large, small and numerous that it’s going to continue to propagate and continue to make the problem worse.”
Indeed, the Feb. 10 collision of the operational 33 telecommunications satellite and the defunct Russian Cosmos 2251 satellite has aggravated the orbital debris situation throughout low Earth orbit, said Nicholas Johnson, chief scientist of NASA’s Orbital Debris Program Office at the
“Coupled with the debris from Fengyun-
, which was destroyed during a Chinese anti-satellite test in 2007, the amount of cataloged debris has increased approximately 40 percent compared with all debris left over from the first 50 years of space exploration. This is a dramatic and significant increase in only two years,” Johnson told Space News in an April 7 e-mail.
Johnson said the principal risk to spacecraft in low Earth orbit arises from debris that are too small to be cataloged by the U.S. Space Surveillance Network since the smaller debris far outnumber the cataloged population.
“The 2007 anti-satellite test and the 2009 spacecraft collision also contributed markedly to the number of small debris in orbit,” Johnson wrote.
Kaplan characterized space debris as a growth industry – one that is international in scope and demands global solutions. “Every country that flies in space, or uses space for applications, will be affected … and that is every country, period.”
While Kaplan said nations would be hard-pressed today to justify the expense that cleaning up low Earth orbit would entail, he said he believes the time is approaching when the cost-benefit calculation will flip. “We don’t know exactly where that point is, but I’m going to guess it’s within the next 10 to 20 years … maybe sooner, maybe later … we don’t know.
“But there will be a day when we’re going to say we cannot use space anymore unless we do something,” Kaplan continued. “That’s the day we start cleaning up space. I guarantee that cleaning up space is the next space age because it’s going to take a major new space program – not just one mission – just to clean this stuff up. Reduction will become imperative.”
APL’s bid to push forward on orbital debris reduction research, while still embryonic, includes brainstorming a mix of ground-based and space-based experiments to help identify promising approaches for actually collecting orbital debris. APL is considering holding a workshop, possibly this summer, to assist in shaping a research agenda, Kaplan said.
All manner of de-cluttering ideas have been proposed over the years, from shooting debris with lasers to deploying huge orbiting nets that snare bits of flotsam.
“But most of the people that come up with ideas don’t really appreciate the magnitude of the problem and the complexity of the solution,” Kaplan said.
Johnson said that since it is inevitable that objects in space will continue to collide, “[t]he challenge is to curtail the number of future collisions via operational and remediation measures.”
NASA continues to be very interested in concepts for removing debris from Earth orbit, and numerous proposals have been evaluated, Johnson said. Some proposals are focused on removing small objects, while others focus on large objects. Some are best-suited for low Earth orbits, some for high Earth orbits. The concepts include ground-based, air-based and space-based removal systems, he said.
“Any evaluation of these proposals must consider technical, cost and international policies issues. To date NASA has not been assigned a mission to undertake a formal orbital debris removal program, although we continue basic research in this field,” Johnson said.
Kaplan said it is time to kick-start active work on orbital debris reduction.
“Right now we’re in the ‘whose fault is it?’ blame game. It’s a typical thing that happens,” he said. “Let’s stop worrying about the past and start fixing the future.”
Becky Iannotta contributed to this article from Washington