Shortening the time satellites stay in orbit after their missions are completed is one of the most cost-effective ways to solve the orbital debris problem, according to a NASA report.

The report, released May 20 by NASA’s Office of Technology, Policy and Strategy, is a follow-up to a March 2023 report on the effectiveness of debris disposal methods or disposal methods. The scope of the new report has been expanded to include strategies to alleviate or prevent congestion and monitor improvements.

The study found that one of the most cost-effective approaches was to reduce the time for so-called debris disposal after the mission was completed. This is the time required for the satellite to be removed from orbit after completing its mission. U.S. government regulations based on international guidelines require satellites to be removed from orbit after 25 years. However, the United States Federal Communications Commission has adopted rules that will go into effect in September this year and will shorten the satellite destruction period to five years after the end of the mission.

NASA research has shown that even smaller reductions in post-mission disposal times provide significant benefits. “We estimate that the benefits of moving to a 15-year period exceed the costs by 20 to 750 times and could create net benefits of up to $6 billion,” the report said.

A shorter time frame could offer higher net benefits of up to $9 billion in a scenario where the spacecraft deorbits immediately after mission completion, albeit at a lower cost-benefit ratio. In all scenarios considered in NASA’s study, reductions in post-mission disposal times result in a cost-benefit ratio greater than one, meaning the benefits outweigh the costs.

While the study found that improving post-flight disposal as a debris reduction measure was highly effective, it also identified the benefits of some approaches to debris remediation. The most promising is so-called “just-in-time” collision avoidance, which involves using lasers or other technologies to push large pieces of debris that risk colliding with each other.

According to the report, the cost-benefit ratio of these approaches is similar to the cost-benefit ratio of the most promising mitigation approaches; He adds that uncertainties in the models could make the improvement even more promising. “We urge the space community to recognize that recovery performance can be comparable to, and possibly better than, mitigation and tracking,” the report concluded.

Other promising tools based on cost-benefit analysis include adding some degree of shielding to spacecraft to guard against collisions and improving tracking of “high-risk” communications to allow satellite operators to make more informed decisions about collision avoidance maneuvers. However, there are significant uncertainties in these estimates, especially regarding conservation.

Other methods received surprisingly low scores. Improving spacecraft passivation (removing energy sources from batteries and fuel tanks that could cause an explosion to create debris) has not yielded a net positive benefit for 30 years, even in the most optimistic scenarios, because the cost of implementing passivation measures is greater than the cost of implementing them.

Although the study included significant technical analysis, its results were expressed in financial terms. “By measuring everything in dollars, we can directly compare protecting the spacecraft to tracking down smaller debris, or removing 50 large pieces of debris versus 50,000 smaller pieces,” Jericho Locke, the report’s lead author, said in a statement. said.

The new study comes a month after NASA announced a new Space Resilience Strategy that highlights the need to better characterize the orbital debris problem before developing technologies to solve it. This involves developing a framework for assessing site sustainability and determining which uncertainties are most important to address.

“This research is part of NASA’s work to rapidly advance our understanding of this environment by applying an economic perspective to this critical issue, as outlined in NASA’s recently released Space Sustainability Strategy,” said Charity Weeden, NASA Deputy Administrator for Technology, Policy, and Policy. said. strategies.