
It is like flying through airspace saturated with pieces of every aircraft from the previous fifty years, blind.
DEBRIS OR NOT DEBRIS
Talking Tea, Trash and Destiny with Rising Star Harriet Brettle
15 November 2019 A debris shield that was removed from the Alpha Magnetic Spectrometer (AMS), the International Space Station's cosmic particle detector, is pictured drifting away from the orbiting lab. The debris shield was detached by spacewalkers so they could access and begin the repairs of the AMS thermal control system. Credit: NASA
I find myself in Old Street, London. My meet is at the aptly named Ozone Coffee. My guest: Harriet Brettle, a finance analyst turned next-generation space-guru set on making space sustainability a reality. Her forte: bringing the thorny issue of space debris far above our heads into the competitive commercial and public spotlight. I say far, it’s as heavenly as the distance between Paris and Amsterdam, about one vertical Eurostar trip away.
We thawed inside on two bar stools, footrests hovering two inches below comfortable. Harriet has better credentials than most BA Mathematics graduates could dream of (and only seven years after leaving university). An intern at JP Morgan, then a graduate at the Bank of England before uprooting herself to become a senior analyst at the Federal Reserve Bank of New York, then returning to the UK to continue her work at the Bank of England; finance seems to have been the foregone conclusion. What changed? Harriet characterises this shift in focus from ‘I.O.U.’s to ‘U.F.O.’s as taking the “scenic route”.
“Honestly, it’s great to say with hindsight that, ‘Obviously, I’ve got this finance experience and then I got this space experience and now I’ve combined the two,’ but you know, it wasn’t that smart of me. I left university and had no idea what I wanted to do.”
The trouble with finance was that the underlying subject was something Harriet just couldn’t get passionate about. It simply didn’t inspire.
“I started to think about the bigger picture I was like, ‘actually, in ten years’ time, do I want to be here in this industry?’ Maybe not.”
"...when I started to think about the bigger picture I was like, ‘actually, in ten years’ time, do I want to be here in this industry?’ Maybe not.”
While in New York, Harriet saw an opportunity to satisfy a hunger for space by volunteering at public outreach events for The Planetary Society, an organisation advocating for citizen involvement in space exploration. Public engagement struck a chord, but how she might translate that into a career wasn’t obvious.
“I didn’t see how I could do this as a real job because I’m a math major. I’m not an engineer, and I can’t be a rocket scientist and I don’t want to be an astronaut, so how could I combine those interests?”

Undeterred, Harriet returned to the UK and took evening classes in astrophysics. Finding a bridge between finance and the space industry became the big problem for Harriet to solve. Her solution lay in statistics—specifically their use in the hunt for exoplanets: the promisingly rocky, Earth-sized worlds beyond our solar system.
“Somewhat on a whim, I took a vacation to spend a week in California doing this workshop. It was a game changer because I realised that there were things in the exoplanet research field, particularly the use of statistics, where I could see how my finance experience could be useful.
So, I used that to basically frame my application reference to graduate programs to be like, ‘Look, I might not have a traditional route in, but I have relevant experience,’ so that helped me get into Caltech and study planets.”
Harriet Brettle speaking at the 2019 Global Space Congress in the United Arab Emirates.
Harriet arrived intending to complete a PhD but left with a Masters. The reason? The big picture: pure science’s nitty gritty details could have meant missing out on holistic space strategising.
“At Caltech I started thinking, ‘If I’m not going to be a scientist in the industry, what other options are there?’ I still wanted to do something that was technical. I liked the problem-solving element. So for the business side—I get to do all these different things right?”
However, we agree that a Masters in Planetary Science must make Harriet at least half a scientist. A bit like a degree in Geography makes a student half an artist. The drinks arrive and we readjust on our stools. For Harriet, an elegant glass teapot, and for me, a very bitter espresso.
Harriet’s present role as Head of Business Analysis at Astroscale is particularly intriguing. Working for a private company of self-identified ‘Space Sweepers’, tackling our space junk problem must carry a host of unprecedented challenges and opportunities. Few things illustrate the reality of the threat (or German ingenuity) better then when European Space Agency astronaut Alexander Gerst had no choice but to fix a breach by sticking his finger inside a 2mm debris hole in the Station’s hull back in August 2018. The suspected culprit was a paint fleck or bolt from an old satellite. As NASA Ground Control dryly observed at the time, “I don't think that's the best remedy for it."
With analysts currently tracking 26,000 pieces larger than cricket balls orbiting our little rock and another half million the size of Creme Eggs keeping them company, space really does struggle to fit our popular conception of a vast and empty wilderness. That’s before you reach the sobering footnote: a hundred million more Skittles-sized pieces are shooting past at twice the speed of a bullet. So when push comes to shove, space debris is such a vast problem that intermittent private clean-up efforts risk becoming mere drops in the ocean. I pose this conundrum to Harriet.
“So, you’re right. Space debris is a big problem that is going to require more than just one company removing it. The way we see it is that in order to address the problem, you need to be able to develop the technology that can actually do something about [it].”
“It’s a classic environmental problem, like plastic in the oceans or pollution in the atmosphere. Everyone contributes to the problem, no one wants to take individual responsibility."
Astroscale is prepping for ELSA-d, a mission designed to demonstrate the feasibility of the proximity rendezvous and magnetic docking technologies necessary for debris removal—in essence, fishing. By launching two objects into orbit in a single payload—the Servicer (magnet rod), and the Client (magnetic fish)—the company hopes to demonstrate that, alongside exhibiting a host of impressively complex core technologies, fishing really is for everyone.
It’s the large failed satellites, the high mass objects in space which Astroscale is prioritising. After all, as Harriet emphasises, it is much easier to bring down one satellite then wait for it to collide and go about collecting a thousand little pieces like an upset box of supersonic Lego. But that still leaves us with the problem of incentives. Harriet’s main responsibility is to make the commercial and institutional business case for space junk removal. However, the difficulty of getting this issue on the agenda now is that space debris is only a problem, not yet a crisis.
“It’s a classic environmental problem, like plastic in the oceans or pollution in the atmosphere. Everyone contributes to the problem, no one wants to take individual responsibility. If we look at history, things don’t happen until there’s a catastrophic event…the global financial crisis, oil spills [a freak international pandemic, perhaps] and suddenly you need regulations to stop this kind of thing from happening, right? So, we’re trying to be proactive, but that’s very difficult to do.”
For context, it took just two collision events to almost single-handedly double the amount of debris in space. In 2007, China’s ego-flexing resulted in a deeply irresponsible anti-satellite test that generated the largest recorded amount of space debris from a single incident in history. Couple that with the impact between an active US Iridium satellite and a piece of defunct Russian hardware in 2009 known as the Iridium-Cosmos collision, and you get a sense of how terrifyingly easy it is to escalate risk by several orders of magnitude.
Depressingly, it is unlikely that such foolish antics will become less common. In March 2019, India followed China’s example with an anti-satellite missile test, while former President Trump’s codification of the Space Force as the sixth branch of the US military in December 2018 is the comical cherry on the cake of space militarisation which, although gradual, seems unstoppable in the present geopolitical climate. When you throw in the rapidly expanding commercial market, runaway space debris will, as Harriet puts it, “sneak up on us.”
Perhaps. Or, perhaps the problem isn't sneaking at all, with the likes of Amazon’s internet-facilitating Project Kuiper or Space X’s Starlink network representing brazen orbital time-bombs. Take Starlink, a mega-constellation of satellites currently in the process of being launched. The platform received permission from the U.S. Federal Communications Commission to build a flotilla 12,000 strong by the end of the decade. For context, fewer than 9,000 objects in total have been launched into space. Ever. As Harriet elaborates,
“The problem is that the amount of useable space is finite. The more satellites that we put into space, the more debris we get, which means you have a higher risk of collisions. If we compromise one of those orbits that we rely on, particularly for certain services, we’re really putting ourselves in a challenging position.”

A conceptual timelapse showing the buildup of space debris over time in low-earth orbit.
Space is vast, yet useable space is cramped and, ironically, increasingly claustrophobic. We should not necessarily be opposed to these new deployment initiatives, but we should all feel uncomfortable that such an extensive build-up is happening in an environment mostly managed by international agreements legislated in the 1960s and 70s.
Compounding this is the suppression of space data. This sounds marginal, but this may be an even bigger problem. If space operators do not have complete information on what is in orbit and where and when it is heading, it is not just like flying a plane without radar—it is like flying through airspace saturated with pieces of every aircraft from the previous fifty years, blind.
According to Dr T.S. Kelso, the Operations Manager for the Space Data Center, of the 26,000 pieces of large assets in orbit, 2,000 of these are missing because they have not been tracked for more than 30 days, and around another 500 are classified for national security reasons, regardless of whether the satellite is dead or alive. Another 4,000 assets have not shared up-to-date data because existing data-sharing policies place no obligation on operators to do so. As a reminder, these satellites exist in the context of the tens of millions of small pieces hurtling around the planet which cannot be tracked.
The best that stakeholders can do right now is to volunteer as much information as possible about their assets to maximise space situational awareness, reducing the risk of further collisions and by extension, debris creation. As Charity Weeden, the Vice President of Global Space Policy at Astroscale (US) argues, this is the key to cultivating a positive, incentives-based culture that is necessary to normalize space sustainability as the de facto form of operation. However, until multilateral international agreement is reached on data sharing requirements, the situation is unlikely to improve. How this can be achieved is, for the moment, unclear, but evidently space junk and space data cannot be treated separately.
So, are we running out of space in Space? In short, yes. Can we effectively manage the orbital traffic jam? Maybe. I’m keen to know what specific strategies Harriet has to make space operators behave more sustainably. In the UK, if you have a problem with uncollected bin bags, you complain to your local council. Who do you complain to in space?
“[I]t’s interesting you bring up bin bags because part of [what] I’ve done in my job is look at how other industries have solved this problem. So, I’ve been looking at the business models of bin bags!
That sounds stupid, but I’ve learned there’s two ways that people can deal with waste removal. One, is that you buy a bunch of bin bags and the removal of those bin bags is included in the cost, and the other is that you can pay a monthly subscription to have a bin outside your office, and then the council can come and take it away whenever you need it to, right?

What does that model look like? Do we charge a satellite operator every time we go and bring down a satellite, or, do we charge a subscription fee so every year they pay us an amount of money and we commit to keeping that orbit clean to some extent?”
"So, I’ve been looking at the business models of bin bags!”
Like an interstellar bin collection?
“Exactly right. In terms of incentivising customers to pay, the big challenge we have is that unlike other industries there’s no regulation to enforce people to do this, to enforce keeping space clean…”
…and there’s no body to enforce that regulation if it existed.
“What we’re working on is developing the commercial incentives. I’m doing a piece of work right now with the University of Southampton, with Professor Hugh Lewis who is an expert in the modelling of the orbital environment. Looking at theoretical models, you can test what kind of debris removal strategies are effective, and then quantify the effect and the value of those strategies. We’ll be able to say, ‘Look, if you want to protect the orbital environment in which you are operating, we can mitigate your collision risk,’ because we will be able to quantify that in some way. So, the idea is really to strengthen those arguments.”
It's an intriguing solution, a stepping stone toward a fully-fledged orbital insurance policy which could roughly calculate the risk of certain orbits and provide a financial incentive for sustainable rocket launches and satellite deorbiting. While innovative in capturing the commercial self-interest of asset damage mitigation, it cannot be a standalone solution. Ultimately, what we are discussing is private self-regulation as the best-case approach to the problem. Has there been any sort of progress in looking for an institutional actor to play a more governmental role in enforcing these ‘regulations’?
“Right now, the European Space Agency (ESA) and the Japanese Space Agency (JAXA) are both developing Active Debris Removal Missions.”
But Harriet concedes; “they’re basically looking for commercial companies to remove pieces of their own debris”, outsourcing solutions to companies similar to Astroscale rather than developing their own. This isn’t necessarily bad. The private sector has been able to offer more effective solutions to space problems than national space agencies in the past, with cost-efficient access to orbit courtesy of Space X being the most obvious example. Groups with lunchbox names like the ‘United Nations Office for Outer Space Affairs’ and the ‘Committee for the Peaceful Uses of Outer Space’ develop long-term sustainability guidelines, and space operators are encouraged to voluntarily share orbital data. However, as Harriet points out, there is no legal enforcement of these expectations. She ends her assessment on an optimistic note;
“There’s good movement and we just need to keep on going in that direction and actually see it through.”
Let us all hope Harriet is right. The Federal Communications Commission voted on a promising new set of sustainability rules on 23rd April 2020, including an expansion of satellite reporting requirements and an adjustment of the licensing process to favour companies committing to greater transparency for their operations. Controversially, these new rules mandate any satellite operating above the orbit of the ISS to be capable of manoeuvring, sparking concerns that this might hamstring the growth of the affordable and increasingly popular nanosatellite market by mandating costly propulsion methods. It could also damage the American market if foreign governments do not issue similar guidelines. The verdict is out.
But the new rules do also develop the fledgling system of collision liability currently in place by requiring operators to insure their satellites in the event that during their lifetime they damage another. Despite the criticism these guidelines are facing, it is very easy to lose sight of the risk posed by inaction, a vegetative reality all too common in the regulatory arena where this many actors need to reach agreement. So the passing of the measures does represent a bold statement on the seriousness with which the space sector’s largest stakeholder is taking the issue of sustainability.
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