Why Orbital Debris Deserves Our Attention


Christie Iacomini
Prime Movers Lab


Space is getting crowded — fast.

Spacecraft launched per year have increased 10 fold compared to a decade ago. Statistics vary as references are quickly obsolete with each new launch (which alone reinforces the fact that orbital content is increasing rapidly). Regardless, the trend does not appear to be slowing. The latest Euroconsult Analysis predicts an almost quintupling in satellite demand in the next decade.

Much of this growth is fueled by the new low and medium earth orbit mega-constellations, being brought to you by the likes of SpaceX, Amazon, OneWeb, and Telesat to provide relatively inexpensive global telecommunications services. Meanwhile, behemoth communication satellites in geostationary orbits that provide continuous wide-spectrum coverage to an entire continent are not going away. Add to the neighborhood uncontrolled whole defunct satellites unable to complete their mission and relic spent stages of launch vehicles. Then literally pepper the expanse with shards from explosions caused by residual fuel, thermally cycled batteries, or in-space collisions. These millions of smaller pieces go whizzing in and out of orbits given the velocity changes imparted when they were birthed by explosions or collisions.

The threat is growing — faster.

The number of “conjunctions” (when two spacecraft pass near each other) at < 1 km apart currently occurs around 3,200 times per week and is growing, according to Professor Hugh Lewis, the head of the Astronautics Research Group at the University of Southampton, U.K.. Operators make risk assessments on whether to implement collision avoidance maneuvers. This is complicated by trading uncertainties (estimated 100 m for a spacecraft and over 1 km for a piece of debris) with consuming propellant (which could shorten a mission) and possibly temporarily cutting service (which could impact revenues). If a collision were to occur, that could create a cascading effect — known as the Kessler syndrome — as more debris is created and collides with neighboring spacecrafts. This chain event could wipe out the space infrastructure for years to come.

To illustrate the magnitude of potential threats, consider these figures updated monthly by ESA. There are more than 4,700 currently-functioning satellites today. There are almost 2,900 additional inactive satellites still in space. Then there are over 29,000 debris objects larger than 10 cm (or about a softball) regularly tracked and catalogued by the U.S. Space Surveillance Network for purposes of collision avoidance. Over one third of these objects are attributed to only two events: China’s anti-satellite test in 2007, and an accidental collision in 2009 between a retired Soviet Union-era satellite and an operating U.S. spacecraft. The threat of more events like these are frequent, like the near miss of two obsolete spacecraft reported just this April — neither of which can maneuver to avoid collision.

Statistical models estimated there are another 7,000 objects larger than 10 cm not tracked. Just as dangerous, statistical models estimate there are nearly one million objects between 1 cm to 10 cm, and over 330 million objects less than 1 cm (the latter estimate increased 3X in the last 6 months). These projectiles move at speeds faster than bullets and wreak havoc. NASA’s space shuttle has numerous evidence of the damage caused by even the tiniest orbital debris, requiring costly repairs and threatening astronaut lives. Satellites in geostationary orbit are just as vulnerable, which disrupts service and revenues and increases capex (see tracking video that captures the anomaly taking out a telecommunications satellite after only a fraction of its service life). To get a sense of all the debris orbiting the Earth, see this ESA 2019 orbital debris animation (set playback speed to 2x and note the color key to the right).

The threat is not contained to in-space assets. As early as 1997, Lottie William was actually hit by what is assumed to be a piece of a Delta II rocket. And just this past spring, a Falcon 9 second stage pressure vessel (about one and half meters long) landed in Washington state (it was launched from Florida).

It’s got the government’s attention.

This uptick in orbital traffic and threats has commanded the attention of government agencies. ESA partnered with the United Nations Office for Outer Space Affairs (UNOOSA) to create infographics and podcasts specifically to raise awareness of orbital traffic and debris.

In the U.S., the National Space Policy was updated late last year to include a cross-sector (commercial, civil, and national security) space policy to address challenges related to tracking, minimization, and removal of orbital debris.

In March, the U.S. Space Force Vice Chief of Space Operations Gen. David Thompson was advocating for companies to address the problem, “I’ll pay by the ton if they can remove debris.” Space Force amplified that message just last month as part of a keynote at the Advanced Maui Optical and Space Surveillance Technologies, or AMOS, conference, “I think there is a use case for industry to go after that as a service-based opportunity.” Major General DeAnna M. Burt went on to explain that commercial companies are preferred over military-led efforts to avoid the worry of “dual use” (where the technology could also be classified as useful for weapon applications and slow their adoption).

In support of this, last week, Space Force’s business accelerator “Hyperspace Challenge” announced finalists competing for $100,000 to, well, accelerate their businesses. Technology areas included those to affect orbital debris detection, tracking and removal.

Growing demand.

The 2020 global space economy is estimated at $371B per Carie Mullins at BryceTech (report to be released soon, see 2019 report at $366B). Investments in start-up space companies have doubled in the last couple years, achieving $7.6B in 2020. Space company entries into the public sector have also been rapidly increasing since 2019 with $5.1B raised through special purpose acquisition companies at an anticipated $27.1B in combined aggregate market value (see Bryce’s 2021 Start-up Space Report).

The opportunities fueling the next wave are plentiful. We are seeing an increasing number of start-ups rich in diverse applications and technologies that will build upon each other to provide the infrastructure and lower costs for doing business in space.

So what are these market opportunities? Servicing will be in demand for high value large GEO satellites. These assets are worth a lot of money. Keeping them in orbit allows for them to generate revenue for longer. According to a recent Northern Sky Research forecast, demand for extending the operational life of satellites in geostationary orbit is predicted to create a $3.2 billion cumulative market opportunity within the next decade. GEO satellites also don’t want to turn into a liability when they have exhausted their utility or (worse) become unintentionally inoperative. Space tugs could move them to a higher “graveyard” orbit (the propellant for that maneuver is far, far less than what would be required to deorbit and burn up in the atmosphere).

On the LEO side, large constellations may be designed to lose a satellite or two (or 10 or 20). Their low cost may also allow for replacement rather than service. But from the debris side, they may choose to equip themselves for Active Debris Removal (ADR). That is being driven by their business and economic decisions to keep their orbital space clutter-free from self-inducing hazards. ADR may be secondary self-initiated technology to insure deorbit into the atmosphere or hardware that allows a tug to assist.

Over half the respondents at the CONFERS 2021 Global Satellite Servicing Forum (GSSF) last month concluded that space servicing capabilities will immediately contribute the most to achieving sustainability (followed by large-scale science platforms, in-space transportation, exploration, and national security).

So ADR and satellite life extension are the first focus. These capabilities will grow other services. Space tugs will eventually require propellant depots less they become orbital debris themselves. Satellite relocation can then enable customer flexibility. Inspection may be required to assess the state of an inoperative satellite (salvageable or in need of a deorbit assist?). Space tugs could turn into hosts providing functions (like power or comm) that maybe were damaged by small debris, a single event upset, or simply end-of-life. On-orbit 3-D printing may provide repaired solar arrays or antenna booms.

Real progress.

With demand for satellite services rising and governments’ calls to action, the future is bright for us space enthusiasts! Companies large and small are making good traction, and demonstrations are picking up in this sector. Here are a couple recent achievements demonstrated in space.

Addressing legacy assets — In April, SpaceLogistics of Northrop Grumman used one of its Mission Extension Vehicles (MEVs) to extend the operational life of a several-ton communications satellite — by five years. The intent is that after five years, the MEV will have capacity to move on to service other satellites. Turns out this is the second time an MEV has been used to meaningfully extend the life of a commercial space asset. Even more interesting and challenging, the satellites were designed and deployed before remote on-orbit servicing was possible. They now have 7 missions booked with 6 customers, through 2025 and into 2026.

Designing for Sustainability — In March, we saw the launch of Japanese startup Astroscale’s “space sweeper.”Called the End-of-Life Services by Astroscale demonstration (ELSA-d), the mission demonstrated a 175 kg “server” satellite, releasing and capturing a client with a magnetic docking mechanism. This demonstration mission will end by disposing of the client in the Earth’s atmosphere where it will incinerate. OneWeb, which has been adding small magnetic plates to position itself to take advantage of ADR services (see an animation of how that might work), entered into partnership with Astroscale earlier this year.

More to come.

Many missions are in the works. If you want to view something that looks like an alien consuming Earth’s orbital assets (!) then check out ClearSpace. ESA estimates there are almost 2,000 discarded rocket stages that need to be removed. ESA has awarded ClearSpace the opportunity to address these literal space mines using multiple tentacle-like robotic arms. In 2025, ClearSpace-1 will carefully approach and embrace an uncontrolled 100 kg, almost 2.5 meter piece of a rocket booster — without creating any new orbital debris in the process mind you. ClearSpace-1 with its trash treasure will then deorbit and burn up in the atmosphere. An expensive one-off? Yes — but with a solution that doesn’t care if the offending object has a standard grappling fixture or stable attitude.

Speaking of which, we didn’t even touch on standards … or regulations, tracking debris, traffic management to avoid making more debris, technologies under development, and the business cases. We just have to cover those in future blogs.

Maintaining a clean space environment will maintain on-orbit services that keep us protected and connected, guide our travels, inform discoveries and, yes, deliver Netflix uninterrupted. Speaking of which, what program is on for me tonight? Netflix’s Space Sweepers! After I take out the trash…

Prime Movers Lab invests in breakthrough scientific startups founded by Prime Movers, the inventors who transform billions of lives. We invest in companies reinventing energy, transportation, infrastructure, manufacturing, human augmentation, and agriculture.

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