The growth of traffic in LEO shows no sign of slowing down. While exciting, we must be aware of and prepare for the challenges to come. To do that, we’re using this special edition of LeoPulse to provide key data points and insights on the most significant changes and events that occurred in 2022. Our hope is that this annual review will provide crucial context for the new year, one which promises to be even more dynamic than the year past.
The growth of traffic in LEO shows no sign of slowing down. While exciting, we must be aware of and prepare for the challenges to come. To do that, we’re using this special edition of LeoPulse to provide key data points and insights on the most significant changes and events that occurred in 2022. Our hope is that this annual review will provide crucial context for the new year, one which promises to be even more dynamic than the year past.
Skip to "Clusters of massive derelicts" — 03:09
Skip to "Clouds of fragments" — 04:50
Skip to "Constellations of operational payloads" — 10:10
Skip to "Space safety policies and updates" — 11:50
Stay tuned for the 5th edition of LeoPulse coming out in mid-February which will feature a thought leadership piece from our team. If you haven't signed up for our newsletter yet, please do so you don't miss the next edition. Want more content like this right now? Check out the previous editions of LeoPulse. We suggest starting with LeoLabs CEO Dan Ceperley’s guide to potential disasters in LEO.
Access the written article and download the accompanying infographic here.
For more information about LeoLabs, and our products — please visit our website.
Until next time, ad astra! ✨
——— Intro ———
LeoLabs presents LeoPulse: Edition 4
What’s up in low Earth orbit? Insights from 2022
Written by the LeoLabs Data Insights Team: Dr Darren McKnight, Dr Rachit Bhatia, Erin Dale, and Mohin Patel
Published in January 2023
——— Content body ———
Low Earth orbit is a dynamic environment.
In 2007, the number of cataloged objects in low Earth orbit — or LEO — crossed 10,000.
It took nearly 50 years, since the dawn of the Space Age, to add those 10,000 objects. That’s about 200 objects a year on average. Contrast that with late 2021, when the 20,000-object mark was crossed. This time, it took roughly 15 years to amass an additional 10,000 objects in LEO. That’s about 650 objects a year.
Contrast that again with 2022, when the number of objects in LEO increased by around 2,500 — or 13% — to a total of around 21,000. While operational payloads accounted for most of this growth, around 70% of objects in LEO are still space debris. This includes intact derelict rocket bodies and nonoperational payloads, as well as fragments from hundreds of dead satellites.
This growth in LEO shows no sign of slowing down. While exciting, we must be aware of and prepare for the challenges to come. To do that, we’re using this special edition of LeoPulse to provide key data points and insights on the most significant changes and events that occurred in 2022. Our hope is that this annual review will provide crucial context for the new year, one which promises to be even more dynamic than the year past.
Before we dive in, here’s a reminder of how we categorize our insights.
The LEO population consists of three primary components: “Clusters” of massive derelicts, “Clouds” of fragments, and “Constellations” of operational payloads. Each of these components exhibited interesting collision risk patterns in 2022. Using the data collected by our growing global network of phased array radars, we’re going to “demystify” these patterns for you, delving into each and highlighting notable events.
First up? Clusters of massive derelicts.
Many of the largest objects added to the LEO population this year were abandoned rocket bodies. This isn’t new. LEO has been littered with defunct rocket bodies since the early days of the Space Age. It is, however, still consequential. Why? Because these rocket bodies stick around for decades, like wayward zombies wandering around a busy city. In fact, the rocket body from the seventh space launch ever, Vanguard 2 in 1959, is still in LEO today… more than 64 years later.
In 2022, around 50 rocket bodies were abandoned in LEO above an average altitude of 500 kilometers, with an average mass of over 2,000 kilograms. Seven countries account for these abandoned rocket bodies, including every major spacefaring entity except the European Space Agency. More than a third of these rocket bodies originated from China, with two currently in the “bad neighborhood” of 800 to 900 kilometers. It should be noted that there were an additional 24 rocket bodies deposited in higher orbits outside of LEO. These rocket bodies typically stay in orbit even longer.
The “bad neighborhood” we just referenced is where many massive derelicts were historically abandoned. This region continues to be a hot spot for debris collision risk. In 2022, for example, there were 836 conjunctions in LEO with a miss distance of less than 100 meters; nearly a third of these most dangerous conjunctions — 237 instances — occurred in this neighborhood.
Now let’s turn to clouds of fragments.
In early 2022, we observed the rapid rise of cataloged fragments resulting from the on-orbit anti-satellite weapons test conducted by Russia in November 2021. This event, which destroyed the Cosmos 1408 [fourteen o eight] payload, eventually resulted in over 1,800 total cataloged fragments — but never more than 1,200 at once. This number peaked in March 2022 and dwindled to around 400 by December 2022, due to atmospheric drag. Interestingly, despite the rapid decline of the number of fragments in the catalog, the number of Conjunction Data Messages issued involving a fragment from the C1408 breakup did not follow the same trend. This was partially due to the increased number of operational satellites deployed in 2022 that were characteristically threatened by C1408 fragments.
Unfortunately, just as the C1408 fragment cloud was being cleansed from LEO, the Chinese CZ-6A rocket body exploded. This event occurred on November 12th 2022 — soon after it deployed the Yunhai 3 weather satellite into the “bad neighborhood” we mentioned earlier. In turn, this event increased the number of debris fragments in LEO, partially reversing the shrinking trend we were observing. As of January 1st 2023, the total number of cataloged fragments was around 475, a sharp increase from the initial report of around 50 fragments.
Using our LeoRisk tool, we were able to analyze this event, illustrating that while it occurred in the most densely populated region in LEO, the timing of the explosion — soon after deployment — indicates that it was likely triggered by an issue related to the spacecraft’s propulsion system and not a collision-induced fragmentation.
We hypothesize that the explosion may have been triggered by an attempt to vent remaining propellants, an attempt at an orbit-lowering burn, or the rocket stage simply failed to shut down smoothly. The potential of the incident being propulsion-related is reinforced by reporting from astronomer Cees Bassa, who stated in a video by Dan Bush of Missouri Skies that “observations from two consecutive passes over the US in the hours after launch show fuel leaking from the rocket.” Other energy sources on the rocket body likely include batteries and pressurized vessels related to the propulsion system.
To further understand this event, we analyzed the resulting fragment cloud in a Gabbard diagram and a spike plot. The Gabbard diagram for the CZ-6A rocket body illustrates the distribution of objects in LEO from as low as around 320 kilometers to as high as around 1,500 kilometers.
Next, we analyzed a spike plot, which plots the spatial density of the fragment cloud as a function of altitude. This provides an immediate measure of the collision risk posed to other resident space objects from a breakup event. The peak and average spatial density values can be compared to the existing background population levels at these altitudes.
When we analyzed the CZ-6A explosion using a spike plot, we found that the spatial density at 830 kilometers increased after the event. As a result, the collision probability at that altitude rose by around 9%. This percentage increase drops rapidly to less than 2% in the region below 700 kilometers and above 900 kilometers.
By December 31st 2022, we reported 772 conjunctions with a probability of collision greater than one in a million involving a fragment from this event. These conjunctions occurred between 345 kilometers and 1,441 kilometers in altitude. The number of conjunctions with a probability of collision greater than one in a hundred thousand and one in ten thousand were 44 and 4, respectively.
Finally, we used our mapping tool to understand the distribution of conjunction events as a function of time and type of object with which the CZ-6 fragments were conjuncting. We concluded that over a third of the events involved an operational payload and around 12% involved derelict rocket bodies. Of the 94 events involving these derelict rocket bodies, 20 involved the massive Russian SL-16 rocket bodies we’ve talked about before. This cluster of rocket bodies are considered the most problematic dead objects in LEO and therefore the most important to remove through active-debris removal.
Our team at LeoLabs will continue to monitor and characterize the collision risk resulting from the CZ-6A’s fragment cloud, which includes issuing Conjunction Data Messages and assessing the most dangerous encounters in LEO involving these objects.
Enough about space debris, let’s talk about constellations.
While SpaceX’s Starlink has captured the public’s imagination due to its rapid growth — they added around 1,500 payloads in 2022 — several other constellations also grew significantly. These include OneWeb, Planet, Swarm, and Spire Global, which all had double digit percentage growth rates this year. This makes for an exciting — and increasingly dynamic — commercial environment in LEO.
Of course, this growth in operational payloads presents challenges that make space traffic coordination increasingly critical. This is evident in the changing proportion of high probability conjunctions. In particular, we’ve observed an increase in Space Traffic Management conjunctions relative to Space Debris Management conjunctions. A Space Traffic Management conjunction is any close approach that includes at least one operational payload, while a Space Debris Management conjunction is between two dead objects. On average in 2022, there were twice as many Space Traffic Management events as Space Debris Management events, but that’s not the whole story.
Interestingly, earlier in the year, the proportion of events was 40% Space Debris Management and 60% Space Traffic Management. By the end of the year, however, this proportion changed significantly to 80% Space Traffic Management and 20% Space Debris Management. Why does this matter? This indicates an increase in high probability of collision events involving satellite operators, which means it’s becoming more critical for them to procure advanced collision avoidance services and share data related to their satellites’ position in space.
Now that we’ve covered the action in orbit, let’s look at the action on Earth that will impact LEO in the future.
In particular, there were three major policy advancements regarding space safety this year that we’d like to cover.
First, in September 2022, the Federal Communications Commission adopted a new 5-year rule. This rule requires satellite licensees to remove their payloads from orbit within five years after the end of their mission lifetime. This is a significant reduction of the previous 25-year rule. Our team at LeoLabs supported this change due to the growing risks posed by space debris in LEO. This rule change is indicative of national and international entities finally understanding that enhancing space safety in LEO requires leaving less debris in orbit.
Second, the United States spearheaded a call for a global moratorium on destructive, on-orbit anti-satellite testing. In mid-December, the United Nations General Assembly adopted a resolution introduced by the US, with 155 nations voting in favor, nine voting against, and nine abstaining. This initiative reflects the growing concern over the effects from anti-satellite tests, with fragments from the last two on-orbit anti-satellite tests contributing significantly to collision risk in LEO. As we’ve reported previously, more than 25% of all high probability of collision conjunctions in 2022 involved a fragment from these tests.
Finally, US Senator John Hickenlooper and his staff rallied a bipartisan initiative that became the Orbital Sustainability Act, which the US Senate unanimously passed in 2022. This Act seeks to operationalize active debris removal on massive derelict objects that have been left in orbit by previous US Government space missions. It’s exciting to see the US commit to remediate some of the mass in LEO that poses significant debris-generating potential.
In addition to the policies above, this past year was also characterized by growing concern regarding uncontrolled reentries of space objects, specifically rocket bodies, which pose a risk to the environment and human life. In response, the Outer Space Institute published an international open letter calling for “reducing risks from uncontrolled reentries of rocket bodies.” This letter, published on December 19th 2022, addressed space agency leaders in the US, China, Canada, Russia, Japan, India, and Europe. Both LeoLabs Senior Technical Fellow Dr Darren McKnight, a co-author of this report, and LeoLabs Australia President Terry van Haren are signatories.
Before we wrap up this special edition of LeoPulse, let’s briefly return to the numbers. We are the LeoLabs data team after all; numbers are kind of our thing!
As stated in the introduction, there was a net increase of around 2,500 objects in LEO in 2022, that’s four times higher than in the last 15 years. This growth also occurred at a rate 13 times faster than during the first 50 years of the Space Age. The number of objects is just part of the story; however, the mass accumulation is also an important component in understanding future debris-generating potential.
By analyzing the increase of mass and the number of objects in LEO since the beginning of the Space Age, we’ve drawn three major observations:
First, the drastic increase in operational payloads since 2020 is transformational and not expected to slow down soon.
Second, despite the exponential increase in the number of operational payloads, their total mass is still less than the accumulated mass of intact derelicts — such as rocket bodies and non-operational payloads. These large dead objects are likely to be a catalyst for future debris-generating events.
Third, rocket bodies and non-operational payloads were abandoned early in the Space Age, before the turn of the century, at certain orbits. These “clusters” of debris are persistent and account for most of the derelict mass in LEO.
——— Outro ———
And that’s all for now!
Stay tuned for the next edition of LeoPulse coming out in mid-February, featuring a thought leadership piece from our team. But if you want more content like this right now, you can stream all the previous episodes of LeoPulse on Spotify, or wherever you’re listening to this podcast. Be sure to subscribe so you don’t miss a future episode — and leave a rating or a positive review. It helps get our show to more listeners like you.
Until next time… ad astra!