The Gravity of Space Debris
With the commercial space economy poised to fuel another roaring ’20s, space debris is now the big elephant in the room. Are we doing enough to keep our orbits clean?July 24th, 2023It’s early 2019, and most of the commercial space industry is abuzz about the launch of megaconstellations into Low Earth Orbit (LEO), which will deliver a powerful broadband experience to all of mankind.
Chris Blackerby, Chief Operating Officer (COO) at Astroscale, is pumped about a different kind of launch, specifically of the company’s ELSA-d satellite, which is scheduled to launch in the first quarter of 2020, into Low Earth Orbit (LEO). The satellite is designed to facilitate End of Life (EOL) services — helping to bring retired or failed satellites out of orbit and back into the Earth’s atmosphere, where they will burn on reentry, leaving no further debris behind.
Astroscale, which was founded in 2013 as a space-debris removal company, has built an impressive name for itself as an environmental steward of the skies. The company raised $50 million in late 2018 through Series D funding (led by INCJ), bringing total capital raised to $102 million. This year, the company’s to-do list includes seeking partnerships with commercial satellite providers that require a de-orbit plan for future satellites, as well as governments looking to remove current orbital debris. Astroscale also hopes to partner with policy makers and international organizations to develop norms and regulations that contribute to the responsible use of space.
“The industry is becoming more cognizant of the fact that they need to do something to manage debris,” says Blackerby, who works out of the company’s Japan office (the company also has offices in Singapore and the U.K.). “We know we’re addressing a growing concern because we're seeing a lot of other companies trying to get into this space. We welcome the competition because it shows we have identified a viable market.”
The timing couldn’t be more important. There have been an estimated 5,000-plus launches since the space age began in the late 1950s, which have left behind a trail of debris, especially in LEO but also Medium Earth Orbit (MEO) and Geostationary Orbit (GEO). These launches have put about 8,650 satellites into space, according to European Space Agency (ESA) estimates. Of these, about 4,700 are still in space, but only 1,800 are still functioning.
With the momentum around the rollout of megaconstellations from the likes of SpaceX, OneWeb, and others, the potential for creating even more debris is real. But as an industry, we’re only starting to understand downside of having too many satellites, and in some circles, there’s a preference to downplay the potential for disaster. And so we’re left with many unanswered questions: Are new mobile satellites being built with the right “end of life” technology? How likely are future collisions? And how many megaconstellations are too many?
The Clean-Space Crusade
The 2013 film “Gravity” deserves much credit for bringing the topic of space debris into everyday conversation — though many believed the space collision-driven plot for the Hollywood blockbuster, starring Sandra Bullock and George Clooney, was pure science fiction. Today, there’s no doubt that collision of that magnitude — the catastrophic scenario known as “Kessler Syndrome,” proposed by space scientist Donald Kessler in 1978 — is entirely possible, and the impacts are more dire than “half of North America [losing] Facebook,” the hypothetical scenario Clooney’s character suggests as tries to quickly redirect the space mission, before chunks of metal start flying.
What’s possibly scarier than this scenario is that significant, real-life response to the problem of debris didn’t happen years before “Gravity” hit the big screen. To be fair, headline-grabbing collisions were relatively few and far between, like the bullet-size piece of junk flying at high speed that knocked a crater into a European Earth Observation (EO) satellite a few years ago, or the 1,984-pound (900 Kg) non-operational Russian satellite that collided with, and destroyed, one of Iridium’s communication satellites in 2009.
Major collisions don’t happen often, but many believe that they soon might.
“It's like the environmental concerns in the 1950s,” says Blackerby, describing the current debris situation. “People would dump things in the ocean, and they would say, 'oh the ocean’s huge, we’re okay.’ Now we know better.”
As a testament to the importance of keeping orbits as clutter-free as possible, multiple government agencies, including NASA, the European Space Agency (ESA) and the United Nations (UN), to name a few, have ramped up efforts to clean up space.
In 2018, the Scientific and Technical Subcommittee of the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) reached an agreement on nine guidelines intended to reduce the risk of space collisions. The guidelines cover everything from the registration and information sharing of space objects to testing and assessments of them, for example.
Luisa Innocenti, head of ESA’s Clean Space initiative, which launched in 2012, says the ESA is also making strides in numerous ways — from embedding environmental sustainability within space design, to promoting the industry-wide adoption of greener industrial materials and aiding debris-removal missions.“There’s been a lot of progress with our agency, and a lot of activities around clean space —not just the sexy ones of removing junk, but also improving the understanding of the environmental impact of space activities … not only in space, but also on the ground,” Innocenti tells Via Satellite. “In the past we have been building our satellites to survive in space. Now we have to build our satellites to destroy themselves when they come down or to move to some graveyard orbits.”
Leading commercial operators are also showing they care. SpaceX, for example, in 2018 revised its FCC filing to launch 1,584 satellites at 550 kilometers opposed to the 1,110 kilometer orbit it initially proposed, to reduce its orbital footprint.
A Cluster of Challenges
But cleaning up space, and ensuring future missions stay clean, is hard, given the abundance of technological, regulatory and financial issues.
For one, cleaning debris, or building new satellites that comply with best practices, is expensive. It’s not easy to obtain public funding for missions, as ESA’s Clean Space office learned in 2016 when it failed to secure funding for the e.Deorbit mission to remove Envisat, an ESA-owned satellite that performed an Earth-observation mission for 10 years but finally failed in 2012.
For commercial satcoms, dealing with an onslaught of parameters and rules is also challenging.
Mike Gold, Vice President, Regulatory & Policy, for Maxar Technologies, parent company to SSL, says the biggest concern in the future will be finding the balance between regulation and innovation.
“One issue tangentially related to debris that we’ve been trying to tackle is Article 6 of the International Space Treaty [of 1967], which requires nations to provide authorization and continuing supervision of their own country’s space activities,” says Gold. “However, no single federal agency has been given explicit authority for the continuing supervision of commercial activities. Such supervision wasn’t a big concern 20 years ago. For example, if a mission was conducted by NASA, it was supervised by NASA, but with the development of some of these new commercial activities, there is a gap that has developed where, again, no specific department or agency has authority. The problem is that insurers like predictability. So do investors. If the U.S. doesn’t get it right you could see a lot of these companies go overseas for regulatory reasons.”
The Business of Snagging Space Junk
Even still, the business capturing debris (and preventing collisions) is becoming a more “crowded” space, so to speak.
One of the most notable efforts to date is the recent RemoveDEBRIS mission, which launched in April 2018 on a SpaceX Dragon resupply to the ISS (and then deployed in June). The mission is overseen by a consortium of space companies including Surrey Satellite Technology Ltd (SSTL), which designed and manufactured the RemoveDEBRIS satellite platform that hosts space debris removal payloads produced by Airbus, ArianeGroup, CSEM, Inria, Innovative Solutions in Space (ISIS), Surrey Space Centre and Stellenbosch University. The mission utilizes imaging technology and other sophisticated equipment, plus a harpoon and net (produced by Airbus) to capture space debris, starting with the biggest chunks first. [For more, see SIDEBAR].
“To help clear up space it’s necessary to remove the largest pieces of debris first, as these are a huge risk as they could collide with other debris and fragment into thousands of pieces,” explains Alexander Hall, Mission Systems Engineer at Airbus in Stevenage. “The RemoveDEBRIS harpoon and net that can both capture junk the size of a washing machine, as well as robotic arms. These technologies are scalable so can be tailored for capturing a range of debris sizes.”
In Canada, Maxar Technologies’ subsidiary, MDA was commissioned in 2013 by Canada’s Department of National Defense (DND), to develop the Sapphire Satellite, which tracks man-made space objects in Earth's orbit between 6,000 and 40,000 km in altitude, as part of Canada’s continued support of Space Situational Awareness. “The mission is going very well,” says Chris Pogue, president of MDA Government. “As the space economy becomes more ingrained in our lives, the ability to monitor objects and prevent damage will help us to ensure we can effectively use space.”
Meanwhile, MDA’s sibling company SSL is focused on the next generation of orbit-servicing satellites that can perform the repair of existing space structures so that they don’t turn into debris. “There are a lot of technologies being developed from drag-like parachute devices to lasers to nudge you out of orbit,” says Al Tadros, SSL’s VP of Space Infrastructure and Civil Space. “In addition to building satellites at SSL, we’re doing a lot of work on satellite servicing programs and infrastructure, which includes robotics. SSL is addressing issues like, ‘if a satellite dies prematurely, what do you do to move it out of the way?’”
Meanwhile, In the United States, Lockheed Martin is currently building Space Fence, a sophisticated system that will dramatically improve the way the U.S. Air Force identifies and tracks objects in space. This will ultimately help researchers understand the space environment, down to the smallest objects, so we can make more informed decisions.
Preventing a Mass Collision
While organizations and space agencies are concerned with the balance of innovation and regulation, scientists are concerned about catastrophe. Hugh Lewis, a space debris scientist and professor of astronautics at the University of Southampton in the U.K., says what concerns him most is the uncertainty of the fallout from a massive collision: Would this remain an isolated event or would it result in other collisions, with the potential to disrupt global communications or weather forecasting? Would the ground economy suffer? How long would the disruption last?
The University of Southampton's debris simulation model, Debris Analysis and Monitoring Architecture to the GEO Environment (DAMAGE), offers a worst-case scenario. Some of the results show signs that are eerily similar to the scene in ‘Gravity,’ in which fragments from the destruction of a defunct spacecraft were sent flying at huge speeds, knocking out one spacecraft after the next.
But, there is a great deal of uncertainty in the predictions made by these models. “That’s the fundamental problem with extreme events like the Kessler syndrome,” says Lewis. “Because it’s never happened in the past, we don’t know how bad the impact would be if it were to happen in the future.”
While such an extreme event is improbable; it’s not impossible. Therefore, international agencies need to step up their licensing procedures for megaconstellations and other new space proposals. “The FCC approved SpaceX’s license application … they approved 12,000 satellites to go into LEO, seemingly on the basis of a relatively basic orbital debris assessment. In my opinion that’s not comprehensive enough. What’s needed is an orbital debris assessment that matches the complexity of the proposed space systems that we are starting to see from NewSpace companies.”
However, Lewis is encouraged by the fact that companies are thinking more about how to operate with the smallest environmental footprint. “You go back ten or 20 years, and the attitude was, ‘we go forward with our space mission no matter what,’” says Lewis. “Now companies are looking at how to operate in a clean way.” VS