It’s a life cycle: the complex world of space safety explained

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You learn the most after a slight period of confusion.

As an ex-physics professor, I always start my talks with that sentence. Why? Because rocket science — with all its complex graphs and numbers — is a daunting subject. It’s crucial, however, to dive deep into data before “coming up for air” in the form of analysis and, eventually, insights.

The space industry is just starting to emerge from a period of confusion thanks to the growing amounts of data on objects, operational and non-operational, in low Earth orbit (LEO). This data is being fed into increasingly intelligent tools, like LeoLabs’ LeoRisk, that are helping us generate insights and drive operational decisions. These solutions ultimately enhance space safety in LEO.

What I and many others have come to conclude seems rather obvious in hindsight: to keep spacecraft safe, we need to consider the object’s entire life cycle. Common practice for regulators and owner-operators has been to focus on one or two elements of a satellite’s time in space, with the primary focus being collision avoidance. Today’s space environment, however, is more complex and dynamic than ever before, which means we must think through the entire life cycle of a satellite. That starts from design and manufacturing through launch, deployment, orbital operations, and ultimately, retirement and removal.

“What I and many others have come to conclude seems rather obvious in hindsight: to keep spacecraft safe, we need to consider the object’s entire life cycle.” 

Before talking about what the life cycle of space safety looks like, let’s walk through the growth of traffic in LEO and the subsequent risk.

Feeling crowded? A quick review of the growth in LEO

It’s become general knowledge that the number of objects in LEO is growing rapidly. As my team and I explained in our 2022 annual review, there was a net increase of ~2,500 objects in 2022 — that’s four times higher than the annual average we calculated over the last 15 years.  While operational payloads accounted for most of this growth, ~70% of objects in LEO are still space debris. Alongside this growth is mass accumulation, which is an important component in assessing future debris-generating potential.

It’s one thing to talk about these rates of growth, it’s another thing to see it. The time-sequence video below starts from the beginning of the Space Age (i.e., 1957) and includes data from the first few months of 2023. The left panel depicts the number of intact objects (such as operational payloads, non-operational payloads, and rocket bodies) deposited at each altitude annually. The panel on the right depicts the accumulation of mass for each of these three object categories over time.

From this illustration, we can draw three important conclusions:

  • The drastic increase in operational payloads since 2020 is transformational and will continue for the near future.
  • Despite the exponential increase in the number of operational payloads, their total mass is still less than the accumulated mass of intact derelicts; these large derelicts are likely to be a catalyst for future debris-generating events.
  • Rocket bodies and non-operational payloads abandoned early in the Space Age at certain orbits (now called “clusters”) are persistent and account for most of the derelict mass in LEO.

What’s risk got to do with it? 

A lot.

Alongside the growth of traffic in LEO is collision risk, particularly in orbits where massive derelicts were historically abandoned. We refer to these as “bad neighborhoods.” To fully explain this risk, I’d need hundreds of pages, dozens of charts, and strong coffee, but I’ll try to break it down succinctly here.

First, to understand risk to objects in LEO we need to understand how we calculate the probability of collision, or Pc.

The statistical Pc of a single object over time considers characteristics and numbers of all the resident space objects that might cross the object’s altitude. It’s calculated by multiplying four terms together:

  1. Timeframe under consideration
  2. Collision cross-section (which accounts for the object’s size and the average size of the other objects with which it might collide)
  3. Spatial density of other objects in the same altitude region (i.e., number of objects per cubic kilometer)
  4. Average relative velocity between these objects (~12 km/s in LEO)

Note: For a more detailed explanation of calculating statistical collision risk, read our “collision risk story.”

To help us calculate Pc and understand risk in LEO, we’ve created a suite of analytic tools. The linchpin of these tools is our “calculator” for space safety: LeoRisk. This tool allows us to determine the statistical Pc levels from cataloged objects and lethal (currently) untracked debris (as modeled by the European Space Agency’s MASTER model). Other analytic tools that provide supporting insights to LeoRisk include characterizing dangerous objects/orbits and determining the cause of breakup events. Based on our data and analysis, we’ve identified four broad types of break-up events that occur in LEO:

  • Low intensity explosion
  • High intensity explosion
  • Catastrophic hypervelocity collision
  • Non-catastrophic, non-hypervelocity collision

In addition, there are many potentially mission-degrading collision events between operational payloads and debris too small to be tracked currently.

Why do these events matter?

Every time a collision or explosion occurs in LEO, especially at higher altitudes, the harmful results are additive because the debris created from the collision is not cleared from orbit for decades, even centuries. For example, in November 2022, a Chinese CZ-6A rocket body exploded in the “bad neighborhood” of 800 to 900 km. The resulting debris increased the overall number of debris fragments in LEO, which, in turn, increased the Pc at 830 km by 9%. Since the explosion, LeoLabs has observed conjunctions with resulting debris fragments as low as 400 km and as high as 1700 km.

“Every time a collision or explosion occurs in LEO, especially at higher altitudes, the harmful results are additive because the debris created from the collision is not cleared from orbit for decades, even centuries.” 

It’s difficult to generalize what’s going on in LEO because the risk environment differs depending on several factors, including spatial density, object mass, type of object (e.g., small fragments, derelict rocket bodies, operational payloads, etc.), altitude, and more. For example, only 25% of the debris fragments from the Russian ASAT test in November 2021 are still in orbit. However, 80% of the debris fragments resulting from the 2007 Chinese ASAT test are still in orbit. This is primarily because of the influence of atmospheric drag at the location of the event: the Russian test occurred at 500 km while the Chinese test occurred at 865 km.

Finally, we’ve observed an increase in Space Traffic Management (STM) conjunctions relative to Space Debris Management (SDM) conjunctions. A STM conjunction is any close approach involving at least one operational payload, while a SDM conjunction is between two dead objects. On average in 2022, there were twice as many STM events as SDM events, but once you look closer it gets a little confusing. (And that’s okay!) In early 2022, we observed that the proportion of events was 40% SDA and 60% STM. By the end of the year, however, this proportion grew to 80% STM and 20% SDM. This indicates an increase in high-Pc 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.

In the graph above, the orange plotting characters depict SDM events, and the blue represents STM events observed between 1 January 2022 and 15 March 2023. From this illustration we can conclude that there have been over half of a million high-PC conjunctions in LEO during this period. In addition, we can observe that STM and SDM conjunctions peak at different altitudes, with SpaceX, Iridium, and OneWeb constellations clearly standing out.

This data illustrates the simple fact that analyzing collision risk is complicated — and as I like to say, the only generalization that is true is that no generalization is true.

How to mitigate risk and protect a satellite throughout its life cycle

Now that we broadly understand the risk in LEO, let’s discuss how we mitigate that risk and protect operational objects.

For much of the Space Age, hope was our best option. I don’t need to tell you that hope doesn’t get you very far in an increasingly risky situation. Luckily, many satellite owner-operators recognize this and have begun to ensure their spacecraft have a certain level of impact and fault tolerance in the form of on-orbit services, “shelter in place” protocols, or hardware changes. However, more needs to be done to mitigate the collision risk in LEO.
As illustrated in the image below, developed by Dr. Tim Maclay at ClearSpace, not only do we need to improve impact tolerance, but we also need to mitigate and remediate debris, and support collision avoidance.

Collision Avoidance

Let’s look first at collision avoidance (CA). Globally, there has been an increase in efforts to build Space Situational Awareness (SSA) networks and Space Traffic Management (STM) systems necessary to do this more effectively. Situated within these systems, we’ve built a suite of services and products to help protect a spacecraft at every stage of its life; starting from design, invest, insure, launch and operations through regulation, retirement, and remediation. This product suite is powered by our growing phased-array radar network dispersed across the globe consisting of 10 radars across six sites. (Soon to be seven!) These radars collect thousands of data points daily on over 20,000 objects in LEO.

These tools and services assist largely with CA. In particular, they help us understand where constellations overlap, share ephemeris and covariance realism, as well as develop a global set of standards and best practices that are key to ensuring satellites don’t collide with other objects. But collision avoidance can only take us so far. What about space debris or non-maneuverable operational satellites? Here is where debris remediation and prevention come in. To reduce the collision avoidance burden, we must not only reduce existing debris but prevent the addition of new debris.

Debris mitigation

There are several ways to prevent more debris. While increasing impact and fault tolerance on spacecraft and developing better collision avoidance is important, we also need to ban debris-generating events, like ASAT testing. In addition, we need to ensure satellite owner-operators de-orbit their satellites once their missions have ended. Thanks to the US Federal Communication Commission’s (FCC) new 5-year-rule and a global moratorium on destructive, on-orbit ASAT testing, we’re on the right path regarding both issues.

Debris remediation 

Remediating debris is more complicated. This requires actively removing debris from orbit, especially objects in high-risk orbits (i.e., “bad neighborhoods”). While there are promising Active Debris Removal (ADR) technologies in development, it’s still an expensive endeavor. (Although, I’d argue it’s more expensive to the industry not to remove debris!) Due to the expense and required effort, prioritizing the most dangerous objects in the most dangerous orbits is critical for ADR investment and planning.

“Due to the expense and required effort, prioritizing the most dangerous objects in the most dangerous orbits is critical for ADR investment and planning.” 

In 2019, a team of researchers and I identified the top 50 statistically-most-concerning objects in LEO. In 2022, I updated this process using LeoLabs’ suite of analytic tools, which enabled me to leverage a half million high-accuracy depictions of close encounters in LEO. (This data wasn’t available before!) Echoing findings in the original paper, this new analysis confirmed that the 18 SL-16 rocket bodies clustered between 815 to 865 km remain the largest contributors to future debris-generating potential in LEO. While several other abandoned rocket bodies and non-operational payloads were identified as worrisome, this review reinforced the idea that the “bad neighborhoods” centered around ~840 km and ~975 km must be remediated first to reduce the chances of large collision events.

Let’s dig a bit deeper into one example.

Earlier this year, one of the SL-8 rocket bodies identified in the top 50 analysis was involved in a near miss of 6 m with a Cold War-era dead Soviet payload. The Pc for this event was ~10% — that’s extremely high. An operator often considers a collision avoidance maneuver at .001%; events which are 10,000 times less likely than this near miss! As we said at the time, it was too close for comfort.

Unfortunately, these massive derelicts do not have the capability to avoid collisions. There’s nothing we can do, currently, to avoid this kind of dead-on-dead collision. However, this is exactly the type of event that developers of ADR aim to address.

While we know what we want to remove, it’s not that simple. In addition to the price tag, the technology must be proven, and difficult issues examined. How do we safely “remove” a large piece of debris from orbit without harming people or the environment here on Earth? In this case, we’re not eliminating risk; we’re displacing it. What’s more efficient and safer? Nudging debris into another orbit? Tugging it? Grappling it? It’s unclear. Luckily, there are several countries and customers blazing the trail in this area to provide solutions soon.

Out of confusion comes clarity

At this point, you may still be a little confused, but the situation should be getting clearer: we need to monitor and characterize the collision risks in LEO to catalyze and enable responsible action. This is not only for collision avoidance services but also for remediation operations on the horizon. Our analytic tool suite, with LeoRisk as the headliner, is supporting analysis to enhance these activities that span the life cycle of a satellite.

“We need to monitor and characterize the collision risks in LEO to catalyze and enable responsible action.” 

As I said in my introduction, we’re just starting to emerge from a period of confusion in the space industry. By examining LEO as the interaction between constellations of operational payloads, clusters of massive derelicts, and clouds of fragments, we’re starting to demystify the swirl of objects and ideas related to space safety. Do we fully understand the risks in LEO? No, but we have a better picture today than we did yesterday and we’ll have a better picture tomorrow than we do today. Do we have all the technologies we need to keep space safe? Not yet, but they’re on the way. What is clear is we need to think about space safety holistically, starting from before a satellite is launched into orbit and ending once that same satellite has de-orbited.

It’s critical that we as a community come to the same conclusion: space safety is no longer a nice-to-have but an absolute necessity. From there we can continue to build the solutions necessary to keep space safe and sustainable. 

More of a visual learner? We’ve got you covered.  Download this infographic.

Don’t forget! You can also  listen to this article below or on Spotify


 

And that’s all for now folks!

Stay tuned for the special Quarterly Review edition of LeoPulse coming out in mid-April, which will focus on clouds of debris in LEO. 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.

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Note: The findings shared in this report and infographic are derived from the hundreds of thousands of data products LeoLabs’ global network of phased array radars collects daily.

Coverage of the Southern Hemisphere is critical for Space Domain Awareness. Here’s why.

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At 7.8 kilometers per second, it takes around 90 minutes for a satellite in low Earth orbit to complete its journey around the Earth. During that time, it passes over different countries, continents, oceans, and whole regions of our planet. Unfortunately, around half of that journey (i.e., 45 minutes) is somewhat of a mystery due to the lack of global radar coverage, particularly in the Southern Hemisphere.

The role of radars on Earth and in space

Recent news of “unidentified areal phenomenon” (UAPs) across the United States and Canada have sparked a sudden public interest in radars. With that in mind, we’d like to issue a reminder that beyond identifying UAPs, radars are also used for things that our daily lives rely on, like weather monitoring and air traffic control.

“At 7.8 kilometers per second, it takes around 90 minutes for a satellite in low Earth orbit to complete its journey around the Earth. Unfortunately, around half of that journey is somewhat of a mystery…” 

You’ve likely boarded a plane in the middle of a rainstorm before and thought, “How can the pilots see through this? Won’t they hit something?!” Thankfully, this disaster scenario is extremely unlikely due to the breadth of radar coverage that exists on a global scale. From Primary Surveillance Radars (PSR) to Surface Movement Radars (SMR), governments have invested billions in gaining a comprehensive, continuous view of the sky and the ground to ensure air traffic safety. If a plane is approaching another plane or flying into severe weather, these radars provide the necessary data to pilots and air traffic controllers to keep passengers safe.

A similar system is needed for space.

As the traffic in LEO grows, so does the need for space safety and Space Domain Awareness (SDA), which requires comprehensive, continuous coverage of the space environment. In particular, we need to reduce the time elapsed between observations (i.e., the revisit rate) in order to study and monitor activities in space, from potential collisions and satellite maneuvers to proximity operations and anti-satellite weapon tests. This requires not only increasing the number of ground radars intended for space observation but also distributing them geographically. In fact, doing so in the Southern Hemisphere is increasingly important. Here’s why.

The gaps in coverage of the Southern Hemisphere

For most of the Space Age, the identification and tracking of objects in LEO has been a service provided primarily by the US Space Surveillance Network (SSN). This Network, initiated in the 1960s, utilizes a variety of sources for its observation data, including radar, optical, radio, and visual. When first conceived during the Cold War, the Network’s primary mission was to help protect North America from missile strikes and other adversarial activities coming over the North Pole. To complete that mission, the US Government built radars largely in the Northern Hemisphere, across North America and Europe. That national security and geopolitical reality left large swaths of the globe uncovered, with only one radar located in the Southern Hemisphere.

Historically, most of the radars that have been designed to track space objects are decades-old ballistic missile warning radars that only track satellites when not performing their primary mission. In today’s dynamic space environment, however, a dedicated, modern, and more geographically distributed radar network is needed.

More coverage is critical to Space Domain Awareness

Of course, a lot has changed since the 1960’s and the end of the Cold War. Not only has commercial space exploded in the last few decades, but the number of nations with space programs has also increased dramatically.

At the start of the Space Age, there were two primary actors in space: the United States and Russia (formerly the USSR). Today, 13 countries, including the European Union, have proven orbital launch capabilities — around 90 countries have objects in space. Countries in the Southern Hemisphere, specifically the Indo-Pacific region, are increasingly launching their own satellites into LEO for a variety of civilian and military purposes.

“Countries in the Southern Hemisphere, specifically the Indo-Pacific region, are increasingly launching their own satellites into LEO for a variety of civilian and military purposes.” 

In addition to decreasing revisit rates, reducing the time it takes to identify and track newly launched satellites is also important for both space safety and SDA purposes. Newly launched payloads “go in all sorts of different trajectories,” explained LeoLabs CEO Dan Ceperley in a recent interview with Breaking Defense, “so having another radar in another location will pick them up sooner.” Without sufficient coverage, satellite owner-operators, government regulators, national defense agencies, and other stakeholders are left in the dark for at least half of that space asset’s lifetime — this uncertainty and lack of clarity brings risk. 

Recent examples illustrate the critical need for Southern Coverage

As previously mentioned, to strengthen Space Domain Awareness, we must reduce revisit rates. By building more space surveillance radars, especially in the Southern Hemisphere, we’ll do just that.
Based on preliminary research, we found that by adding the LeoLabs Kiwi Space Radar (KSR) located in New Zealand (operational since 2019) and the West Australian Space Radar (WASR) located in Western Australia (operational since late 2023) to LeoLabs global radar network and to the SSN, we will reduce revisit rates. We’ve found that for the majority of cases, we can reduce revisit rates for a subset of high interest objects by 35% (for the 70th percentile; 119 minutes to 51 minutes). By adding more radars in the Southern Hemisphere in 2024, we estimate that we’ll be able to reduce that even further.

Our radar sites in the Southern Hemisphere — equipped with S-band technology — provide convenient observations for conjunction events at very low latitudes. This results in more accurate assessments of conjunctions in the region. A recent close approach just over Antarctica between a derelict SL-8 rocket body and a Cosmos spacecraft illustrates the typical event that we can characterize effectively due to this coverage.

The two graphs below illustrate the state vector position uncertainty of both objects over time prior to the conjunction. As the Time of Closest Approach (TCA) drew closer, our system was able to reduce the position uncertainty to just tens of meters (usually, an operator would likely act on 100 meters). This is largely the result of two factors: 1) the two objects’ orbital stability and 2) our radar coverage. We were able to calculate such low position uncertainty due to the coverage from our two radar sites in the Southern Hemisphere.

The graph below illustrates the “miss distance” of the two derelict objects. The relatively flat line over time indicates that our radar coverage in the Southern Hemisphere provided consistent and reliable measurements of the objects’ relative position.  As a result of the state vector updates closer to TCA due to our radars in the region, the probability of collision (Pc) value provided by LeoLabs (Pc ~2.3e-2) differed from the SSN’s Pc value largely based on the more recent state vector update provided by our radars. (The 19th Space Defense Squadron calculated a Pc about 100 times smaller based on less current radar measurements and different hard body radius estimates.)

In addition to the SL-8/Cosmos event, our team was notified on Monday, 20 February about activity regarding the PRC Test Spacecraft2 (NORAD ID: 53357). Data we received from KSR indicated that the spacecraft had recently deployed a payload for unknown purposes. (See the image below.) In the 24 hours immediately following the activity, we received more than 10 radar passes for both objects thanks to the coverage provided by both KSR and WASR. Although the purpose of this activity is still unknown, we were able to determine the orbits and relative behaviors of both spacecraft and have continued to monitor this activity through our in-house tools.

The solution? Build more radars.

The two events outlined above affirm our reasoning behind building additional radars globally: more coverage means more clarity. Our aim is to continue to increase this coverage, not only of the Southern Hemisphere, but also of the Northern Hemisphere and equatorial regions. In fact, we’d be remiss to not point out briefly the importance of more radars in the Northern Hemisphere. Due to the limited number of radars in this region, an object’s orbit needs to be aligned just right to receive quality measurements. Put simply, we need to build more radars globally to reduce the time between observations and update an object’s state vector more often.

“Our aim is to continue to increase this coverage, not only of the Southern Hemisphere, but also of the Northern Hemisphere and equatorial regions.” 

Existing gaps in global coverage of LEO are not only a threat to space safety but also space security as they provide opportunities for adversaries to maneuver and become “lost.” Commercial radar networks that are equipped with the latest technology and dedicated to space tracking and surveillance are key to closing this gap. While the US Space Surveillance Network has served us well for decades it needs to be augmented with reliable, all-weather radars to secure low Earth orbit — a domain that’s become critical to our daily lives.

More of a visual learner? We’ve got you covered.  Download this infographic.

Don’t forget! You can also  listen to this article below or on Spotify


 

And that’s all for now folks!

Stay tuned for the 6th edition of LeoPulse coming out in mid-March 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.

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Note: The findings shared in this report and infographic are derived from the hundreds of thousands of data products LeoLabs’ global network of phased array radars collects daily.

What’s up in LEO? Insights and analysis from 2022

Short on time?  Listen to this article on-the-go. 

Low Earth orbit is a dynamic environment.

In 2007, the number of cataloged objects in LEO crossed the 10,000-object mark. 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. That’s about 650+ objects a year.

Contrast that again with 2022, when the number of objects in LEO increased by ~2,500 (or 13%) to a total of ~21,000. While operational payloads accounted for most of this growth, ~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.” 

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.

From the ground up: an in-depth look at the traffic in LEO through the year 2022

Before we dive in, here’s a reminder of how we categorize our insights. (Read our first review for a more detailed explanation.)

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 depth of 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.

— Skip to: Clusters | Clouds Constellations —

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. 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, ~50 rocket bodies were abandoned in LEO above an average altitude of 500 km with an average mass of over 2,000 kg. (That’s 150+ times more massive than a 6U CubeSat!) 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 (two are currently in the “bad neighborhood” of 800 to 900 km). It should be noted that there were an additional 24 rocket bodies deposited in higher orbits outside of LEO. These typically stay in orbit even longer.

“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.”

The “bad neighborhood” referenced above (and in our previous reports), is where many massive derelicts were historically abandoned. This region, 800 to 900 km, continues to be a hot spot for debris collision risk. In 2022, for example, there were 836 conjunctions in LEO with a miss distance less than 100 meters; nearly a third of these most dangerous conjunctions — 237 instances — occurred in this neighborhood.

Key takeaways:

  • In 2022, ~50 rocket bodies were abandoned by seven countries above 500 km average altitude with an average mass of over 2,000 kg
  • The “bad neighborhood” of 800 to 900 km continues to be a hot spot for debris collision risk: 1/3rd of the most dangerous conjunctions in LEO occurred here

Clouds of fragments

In early 2022, we observed a rapid rise of cataloged fragments resulting from the on-orbit anti-satellite weapons (ASAT) test conducted by Russia in November 2021. This event, which destroyed the Cosmos 1408 (C1408) 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 ~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 (CDMs) 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 12 November 2022, soon after it deployed the Yunhai 3 weather satellite into an 854/856 km orbit, which is in the “bad neighborhood” we mentioned earlier. (But of course!) In turn, this event increased the number of debris fragments in LEO, partially reversing the shrinking trend we were observing. As of 1 January 2023, the total number of cataloged fragments was ~475, a sharp increase from the initial report of 50+ fragments.

The graph below, created using our LeoRisk tool, illustrates that while this event 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. (Note: Collision Avoidance Burden is simply the annual probability of collision with the cataloged population.)

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.

“We hypothesize that the [CZ-6A] 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.”

To further understand this event, we’ve illustrated the resulting fragment cloud in a Gabbard diagram and a spike plot. The Gabbard diagram for the CZ-6A rocket body, shown below, illustrates the distribution of objects in LEO from as low as ~320 km to as high as ~1,500 km.

The spike plot, shown below, 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. With the CZ-6A explosion, for example, we see that the spatial density at 830 km before the event was 5.6E-8, whereas the fragment cloud from the CZ-6A rocket body peaks at 5.0E-9. As a result, the collision probability at 830 km rose by around 9%. This percentage increase drops rapidly to less than 2% in the region below 700 km and above 900 km.

By 31 December 2022, we reported 772 conjunctions with a probability of collision (PC) greater than 1E-6 involving a fragment from this event. These events occurred between 345 km and 1,441 km in altitude. The number of conjunctions with a PC greater than 1E-5 and 1E-4 were 44 and 4, respectively.

This figure from LeoLabs’ mapping tool shows the distribution of conjunction events as a function of time and type of object with which the CZ-6 fragments were conjuncting. Based on our analysis, 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 massive SL-16 rocket bodies, which are considered the most problematic dead objects in LEO and therefore the most important to remove through Active Debris Removal. (Learn more about the clusters of SL-16 rocket bodies in our previous report.)

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.

Key takeaways:

  • Two notable events contributed to collision hazard from debris clouds: the on-orbit anti-satellite weapons test conducted by Russia in November 2021 and the CZ-6A rocket body explosion in November 2022
  • The CZ-6A explosion occurred in the “bad neighborhood” of 800 km to 900 km; the collision probability from these fragments increased by 9% at the center of the cloud at 830 km

Constellations of operational payloads

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 ~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 last 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 (i.e., PC > 1E-6). In particular, we’ve observed an increase in Space Traffic Management (STM) conjunctions relative to Space Debris Management (SDM) conjunctions. A STM conjunction is any close approach that includes at least one operational payload, while a SDM conjunction is between two dead objects. On average in 2022, there were twice as many STM events as SDM events, but that’s not the whole story.

“It’s becoming more critical for [satellite operators] to procure advanced collision avoidance services and share data related to their satellites’ position in space.”

Interestingly, earlier in the year, the proportion of events was 40% SDM and 60% STM. By the end of the year, however, this proportion changed significantly to 80% STM and 20% SDM. Why does this matter? This indicates an increase in high-PC 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.

Key takeaways:

  • Several companies experienced double digit constellation growth rates in LEO in 2022
  • We observed two times as many Space Traffic Management (STM) conjunctions relative to Space Debris Management (SDM) conjunctions: earlier in the year the proportion was 40% SDM and 60% STM but this flipped by the end of the year to 80% STM and 20% SDM

Kept your eye on the sky? Other updates you may have missed

Now that we’ve covered the action in orbit, let’s cover the action on Earth — specifically three major policy advancements regarding space safety.

In September 2022, the Federal Communications Commission (FCC) adopted a new 5-year rule, which 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. (For example, NASA recently cancelled a spacewalk due to the threat of space debris hitting the International Space Station.) This rule change is indicative of national and international entities finally understanding that enhancing space safety in LEO requires leaving less debris in orbit.

Similarly, the United States (US) spearheaded a call for a global moratorium on destructive, on-orbit ASAT testing. In mid-December, the United Nations General Assembly (UNGA) 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 ASAT tests: fragments from the last two on-orbit ASAT tests (i.e., Fengyun 1C and Cosmos 1408) contributing significantly to collision risk in LEO. As we’ve reported previously, more than 25% of all high-PC conjunctions in LEO 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 (ADR) 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 characterized by a 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 19 December 2022, addressed space agency leaders in the US, China, Canada, Russia, Japan, India, and Europe. Both LeoLabs Senior Technical Fellow Dr Darren McKnight (co-author of this report) and LeoLabs Australia President Terry van Haren are signatories.

One last thing…

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 ~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. Mass accumulation is also an important component in understanding future debris-generating potential. (For more information, read our guide to calculating collision risk.)

“There was a net increase of ~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 time-sequence video below starts from the beginning of the Space Age — around 1957, when the Soviet Union launched Sputnik — and ends in 2022. The left panel depicts the number of intact objects (such as operational payloads, non-operational payloads, and rocket bodies) deposited at each altitude annually. The panel on the right depicts the accumulation of mass for each of these three object categories over time.

From this illustration, we’ve drawn three major observations:

  • The drastic increase in operational payloads since 2020 is transformational and not expected to slow down soon
  • Despite the exponential increase in the number of operational payloads, their total mass is still less than the accumulated mass of intact derelicts (i.e., rocket bodies and non-operational payloads); these large derelicts are likely to be a catalyst for future debris-generating events
  • Rocket bodies and non-operational payloads abandoned early in the Space Age (before the turn of the century) at certain orbits (now called “clusters”) are persistent and account for most of the derelict mass in LEO

— Return to: Clusters | Clouds Constellations —

More of a visual learner? We’ve got you covered.  Download this infographic.

Don’t forget! You can also  listen to this article below or on Spotify


 

And that’s all for now folks!

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.

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Note: The findings shared in this report and infographic are derived from the hundreds of thousands of data products LeoLabs’ global network of phased array radars collects daily.

Thank you, next: a look back and a step forward into the new year

There’s an old belief that our perception of time changes as we get older; it quickens. What used to feel like hours begins to feel like mere minutes.

For us, this rang true in 2022.

This past December, we celebrated our seventh birthday. In human years, this is still considered young, but in startup years, we’re officially transitioning into adulthood. As our CEO Dan Ceperley wrote in November, we’re no longer a “small startup” but a “growing, global company.”

Since 2017, when we unveiled our first fully owned and operated phased-array radar facility, we’ve grown as a team, as a company, and as a leader in Space Traffic Management and Space Situational Awareness. Much of that growth occurred this past year, in what felt like flashes of brilliance, innovation, and leadership colliding to create a vigorous energy that propelled us to achieve goals we only just imagined. So, before we say goodbye to 2022, we’re excited to list a few of our milestones and achievements.

Welcomed new experts

We were thrilled to welcome dozens of new team members across the organization, from sales and marketing to operations and engineering. In particular, the inclusion of world-renowned experts have elevated the quality of the data and insights we share with our customers and the public. Curious what we mean? Check out LeoPulse, where these experts share analysis and insights that you can’t find anywhere else.

P.s. Our annual review of LEO will be published in mid-January. Sign up today for our newsletter so you don’t miss it.

Provided humanitarian aid for Ukraine

Following the Russian invasion of Ukraine in February, we joined the Space Industry for Ukraine (SIFU) initiative, contributing money to provide immediate humanitarian aid to the people of Ukraine. By early December, the funds raised by this initiative — around $895,000 — were used to assist over 247,000 refugees and support 9,500 evacuations. These funds were also used to deliver heating supplies to 103 families and more than two million pounds of additional aid across Ukraine.

Supported reducing space debris

Throughout 2022, our experts have taken the opportunity to speak out about the increasing threats posed by space debris in LEO and have suggested measures to help mitigate the risk of collisions. This included supporting the US Federal Communication Commission’s 5-year-rule change for de-orbiting dead satellites and the growing calls to ban anti-satellite weapon (ASAT) tests. Our Senior Technical Fellow Dr Darren McKnight and LeoLabs Australia President Terry van Haren also recently signed the Outer Space Institute’s international open letter calling for “reducing risks from uncontrolled reentries of rocket bodies.”

Won new government customers

We received two significant government awards this year. The first is an award to support the Japan Air Self Defense Force with Space Domain Awareness (SDA) data, services, and training generated from our growing global network of phased array radars and in-house expertise. The second award is to provide data and services to the United States Department of Commerce to support the development of a national, civil-led Space Traffic Management (STM) system. Both awards confirm our position as the world’s leading commercial provider of low Earth orbit (LEO) mapping and Space Situational Awareness (SSA) services.

Freshened up our look

As you may have noticed, we’ve got a new look. In early December, we shared our new branding, which includes an updated logo, revised brand colors, a bold mission statement, a more fluid website, and more. This rebranding effort reflects our transition into “adulthood” as we embrace our growing role as a leader in today’s dynamic space era. Plus, it’s pretty fresh. (If you haven’t checked out what’s new yet, take a peek here.)

Unveiled LeoLabs Vertex™

Finally, as part of our rebrand, we unveiled LeoLabs Vertex™ — the world’s first vertically integrated commercial space operations stack tracking LEO at scale. LeoLabs Vertex™ is the backbone of our operational infrastructure, enabling us to track resident space objects and characterize events for our customers.

This system includes our global radar network, our cloud data platform, and our newly branded, comprehensive product suite.

We’ll share a more in-depth guide to LeoLabs Vertex™ soon; stay tuned by following us on Twitter, LinkedIn, and Instagram.

Looking forward: here’s to the year ahead

Now that we’ve had a quick look back at this year, it’s time to take a small step forward into the next. In 2023, we’ll expand our global radar network (exciting updates coming soon!), as well as elevate our software stack and service levels. We’ll also work with our customers to identify additional SDA and STM services and products that can help fulfill the needs of the burgeoning space industry.

And with that, it’s almost time to say “thank you, next” to 2022. Before we do that, however, we’d like to leave a special note for our team and our customers: thanks for growing older and wiser with us, we can’t wait to speed through another year with you.

We wish you all a happy New Year! 🎉

Tidying up: the three pillars to cleaning up space

Short on time?  Listen to this article on-the-go. 

Space safety and sustainability are complicated topics, touching on various technical, political, and legal questions. But there’s one question that matters most: how do we keep space clean?

First, we need to understand that there are only two types of human-made objects residing in low Earth orbit: those that serve a current purpose and those that don’t. Those that serve a purpose are operational satellites and spacecraft, such as the International Space Station, earth imaging systems, and communication payloads. Their power’s turned on, they’re transmitting data to their teams on the ground, and they’re fulfilling their intended mission every day.

“There’s far more space junk currently in low Earth orbit than there are operational satellites…we must take special care to maintain a safe operating environment for operational satellites for years and decades to come.” 

Then there are the objects still in orbit that no longer serve a purpose. There’s another name for these: space junk. This includes debris fragments, rocket bodies, and defunct satellites. Unfortunately, there’s far more space junk currently in low Earth orbit than there are operational satellites. That means we must take special care to maintain a safe operating environment for operational satellites for years and decades to come. To do that, we must minimize the amount of space junk added to LEO over the long term.

Towards that end, let’s consider three best practices for combating space debris:

•    Collision Avoidance
•    Debris Mitigation
•    Debris Remediation

First up? Collision avoidance.

Collision Avoidance

For a satellite owner-operator, Collision Avoidance means taking an active approach in ensuring their satellites don’t collide with other objects. This is tied to Space Traffic Management, a term you may have heard before. The goal of Space Traffic Management is to ensure that satellites and spacecraft can operate safely in orbit and not collide with other objects. Satellites that are maneuverable can and do fire their thrusters periodically to mitigate the risk of getting hit by other objects in space, especially when they pass within a close range of one another. But these operational satellites only account for a fraction of the total objects in low Earth orbit, which means that STM only addresses a relatively small percentage of the total conjunctions, or “close approaches,” occurring each day. But in LEO, any random object can hit any other random object, so how do we address this risk in the long term?

This is where Space Environment Management comes in, a phrase coined by LeoLabs Senior Technical Fellow Dr. Darren McKnight and ClearSpace CTO Dr. Tim Maclay in a 2019 research paper.

Whereas Space Traffic Management can be thought of as a continuous, daily activity integrated into the operational workflow of satellite owner-operators, Space Environment Management is more preventative and proactive in nature. Think of it this way: Space Traffic Management says, “Avoid that piece of debris today.” While Space Environment Management says, “Let’s keep space clean now to ensure less debris is generated in the future.”

OK, now let’s turn our attention to best practices number 2 and 3. Both of which fall under the umbrella of Space Environment Management. 

Debris Mitigation

Debris mitigation means taking proactive steps to prevent the creation of debris later down the road. Examples of this include designing spacecraft with appropriate shielding to mitigate against threats of collisions from small debris. In addition, spacecraft can be designed to prevent systems, such as batteries or fuel tanks, from rupturing. Finally, owner-operators can also make sure their satellites de-orbit soon after their job is done.

Historically, owner-operators were required to de-orbit their satellites a maximum of 25 years after they became non-operational. The US Federal Communications Commission recently changed this de-orbit maximum time to 5 years to more efficiently mitigate the growth of debris in LEO.

Debris Remediation

Debris remediation refers to removing existing debris from orbit to clean the space environment today, which also serves to lessen the chances of collisions in the future. If Debris Mitigation says, “Don’t make a mess,” Debris Remediation says, “Clean up your mess.”

In the realm of possible conjunction events, the category of “junk vs. junk” (or one random defunct object colliding with another) is in fact the most statistically concerning and the most likely to happen next. That reality has led commercial companies, such as ClearSpace and Astroscale, to develop exciting technologies around Active Debris Removal to de-orbit defunct satellites and dangerous rocket bodies.

As the two rules above indicate, although Space Traffic Management and Space Environment Management are separate in premise, they are tightly interconnected. By practicing effective Space Environment Management today, it will make Space Traffic Management that much more efficient and manageable tomorrow. Likewise, Space Traffic Management is itself a form of Space Environment Management, as it’s one of the most effective ways to prevent collisions and the generation of new debris.

A bottle of soda sits on the edge of a table, what do you do?

Let’s summarize with one final analogy. You’re in your living room with a bottle of soda sitting precariously close to the edge of your coffee table. The soda used to serve a purpose: it was a tasty beverage, but you only drank half of it and now it’s a two-day old, flat soda with a fly in it. You sure as heck aren’t going to drink it anymore. And oops, the cap is also off the bottle. Disaster awaits.

This scenario is addressable with actions geared toward Avoidance, Mitigation, and Remediation.

Warning on Facebook 15.0 Avoidance says, “I should pay attention so I don’t knock that bottle over, because if I do, it’s going to make a giant mess.”

Pouring Liquid on Facebook 15.0 Mitigation says, “I better put the cap back on the bottle, so in case I do knock it over, it won’t make a mess.”

Broom on Facebook 15.0 Remediation says, “You know what, I was done with this drink two days ago and now it’s just cluttering up my table. Plus, I might accidentally knock it over any minute. I probably should have done this earlier, but I’m finally going to throw it away (or better yet, recycle it).”

“Collision avoidance, debris mitigation, and debris remediation are our way of avoiding the ultimate bad outcome in space: creating an environment that doesn’t allow for the safe operation of satellites, which have become essential for a thriving space economy.”

All three actions are aimed at avoiding the ultimate bad outcome — knocking that bottle over and spilling soda on your beautiful white carpet, leaving a permanent stain.

Collision avoidance, debris mitigation, and debris remediation are our way of avoiding the ultimate bad outcome in space: creating an environment that doesn’t allow for the safe operation of satellites, which have become essential for a thriving space economy.

Finally, I’d be remiss not to mention the importance of Space Situational Awareness, which entails tracking all those objects that aren’t transmitting signals. That’s what we do here at LeoLabs. Space Situational Awareness capabilities provide the foundation in which effective Space Traffic Management and Space Environment Management are possible. Without it, we wouldn’t be able to keep space clean.

For decades, low Earth orbit has grown cluttered — now is the time to stop that trend in its tracks. Thankfully, we increasingly have the tools, and the will, to do so.

More of a visual learner? We’ve got you covered. Download this infographic.


Don’t forget! You can listen to LeoPulse on Spotify


 

And that’s all for now folks!

Stay tuned for the 4th edition of LeoPulse coming out in mid-January, which will be a special review of everything that happened in low Earth orbit in 2022. If you haven’t signed up for our newsletter yet, please do so you don’t miss the next edition. Have a suggestion about what we should cover? Let us know by emailing our editor Victoria Heath at vheath@leolabs.space with the subject line: LeoPulse suggestion.

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Note: The findings shared in this report and infographic are derived from the hundreds of thousands of data products LeoLabs’ global network of phased array radars collects daily.

Cosmos 2082: a collision risk story

The collision risk in low Earth orbit (LEO) can be a confusing mix of terms and equations. To better understand the importance of collision risk for the short-term safety of operational constellations and long-term sustainability of LEO, we will follow an individual space object through a sequence of risk calculations. This process will clarify and highlight the need for continuous monitoring and characterizing of all components of the LEO space population in order to catalyze actions to control the growth of debris.

Key characters in our story

On May 22, 1990, the Soviet Union launched Cosmos 2082, an Electronics Intelligence (ELINT) satellite with a mass of 3,250 kg, into an 850 km circular orbit. The Zenit-2 launch vehicle (also called SL-16) deployed this satellite and the upper stage from this launch vehicle was left in a similar orbit to Cosmos 2082. Cosmos 2082 has the International Designator (INTLDES) 1990–46A (i.e., the primary object of the 46th launch of 1990) and the NORAD ID 20624 (i.e., the 20,624th object cataloged by the 18th Space Defense Squadron of the United States Space Force). The SL-16 rocket body has a mass of 9,000 kg, is roughly 11 m in length, and has a diameter of 4 m. Its INTLDES is 1990–46B and Satellite Number 20625.

A model of Cosmos 2082, which featured the Tselina-2 system (Public Domain).

The practice of leaving a rocket body along with a deployed payload was used by many space operators in the 1980s and 1990s. Both objects have now been in orbit for over 32 years, circling the globe over 165,000 times. The distance these two objects have traveled is just under eight billion km; this is equivalent to a round trip from the Sun to Pluto and back!

The SL-16 rocket body is similar in mass and dimensions to a school bus — except it’s going 7.5 km/s, has no brakes and a steering wheel.

The plot thickens

On 5 June 2022, the S-16 R/B 20625 was involved in a close approach with another derelict rocket body, the 37 kg Scout X-4 upper stage, deposited in LEO in 1964 by the United States to deploy Explorer 25 (INJUN-4). The Conjunction Analysis Report, provided by LeoLabs, details this conjunction of 500 m (+/- 100 m) miss distance with a relative velocity of 8.7 km/s (i.e., ~17,000 mph), and a probability of collision (PC) of 1.3E-3 (i.e., ~1/800 chance).

While this may seem like a low probability, typically an operational spacecraft in LEO will take evasive actions if an encounter has a PC greater than 1E-5 (i.e., a hundred times less likely than the close approach that occurred in June).¹

The Conjunction Analysis Report summarizes what is included in a Conjunction Data Message (CDM). The figure below depicts how the CDM provides the PC between two distinct objects for one specific encounter.

Further, so far in 2022, object 20625 has been involved in a total of eight events with a PC greater than 1E-5, shown in the table below from the LeoLabs platform.

That large number of high PC conjunctions shown above is only the tip of the iceberg. During the first nine months of 2022, there were 298 conjunctions with a PC greater than 1E-6 for this specific SL-16 R/B. The distribution of the objects 20625 is encountering in orbit over time is shown in the figure below, produced by the LeoLabs mapping tool. While most of the encounters are with fragments, there were nine events with operational payloads and two with rocket bodies. This hints at the larger perspective of all objects in the vicinity of our SL-16 RB 20625 posing a collision risk to this massive derelict.

Statistical Probability of Collision (PC)

The statistical PC for a single object from all of the resident space objects that might cross the object’s altitude is determined using an equation that considers the object’s size (i.e., collision cross-section) multiplied by the spatial density of other objects (i.e., number of objects per cubic kilometer) multiplied by the relative velocity between these objects (~12 km/s in LEO).²

LeoRisk, a LeoLabs product, provides a way to determine the statistical annual PC levels and what objects contribute to the collisional hazard for any object in LEO. As shown in the figure below, the types of objects 20625 encounters throughout the course of the year to reach 1.57E-3 PC, statistically, are very similar to the distribution of objects from the CDMs issued during the first nine months of 2022. Note that the summation of the CDM PC values will not necessarily be equal to the statistical PC level over a short time period, such as a year or two. In fact, it may take a decade or more for these values to line up, if at all.

The consequence of some of these events with 20625 may range from minor to very consequential. For example, a fragment impact on 20625 may create hundreds of pieces of debris while a collision between 20625 and the Tselina-2 satellite (20624) that it deployed would likely create over 15,000 cataloged fragments and many more lethal, small debris that are not yet trackable. Now, let’s examine how likely it is for these massive objects (i.e., SL-16 RBs and non-operational Tselina-2 satellites) to collide in LEO.

Cluster 850 as a hotspot in LEO

The original characters in this risk story, 20624 and 20625, were part of a larger deployment by the Soviets Union and eventually, the Russian Federation. In total, from 1985 to 2007, 18 ELINT satellites and their associated 18 SL-16 upper stages were deposited between 825 and 865 km. While our previous collision hazard calculations examined either a single event between two objects against each other (i.e., a CDM) or an annual risk for one object vs all other space objects it could possibly encounter (i.e., statistical PC), a collision rate (CR) can be determined among any subset of objects. In this case, that subset is these 36 massive objects deposited centered around 850 that we call Cluster 850 (C850).

This dynamic is depicted in the figure below.

These 36 objects alone amount to 208,000 kg, which is equivalent to over 50,000 3U CubeSats. CR is a relevant concept when any collision event amongst a population is meaningful.³ In this case, the catastrophic collision between any two objects in C850 would likely create over 15,000 cataloged fragments — nearly doubling the LEO fragment population in one instance. This debris would likely be spread over many hundreds of kilometers. For example, the debris cloud from the fragmentation of the Chinese Feng-yun 1C satellite in 2007 at 860 km has been regularly involved in conjunctions at altitudes as low as 300 km and as high as 1,400 km in 2022. It is also important to note that debris created at these altitudes will linger for centuries.

The current annual collision rate within C850 is 1.7E-3 (i.e., a 1/580 chance each year). The importance of C850, however, is amplified when we remember this ensemble of derelict mass has been whizzing past each other for decades (i.e., to Pluto and back). Taking this into account, the probability that the first collision between these objects could have occurred by 2022 is 5–6%. By 2040, this expectation will increase to 8–9% without any intervention such as removing some of these objects. The 18 SL-16 RBs in C850 have been highlighted on numerous occasions as posing a significant debris-generating potential in LEO and have been identified as 18 of the top 50 objects that should be removed from LEO.⁴

The “big picture”

Satellite 20625’s 32-year transit around Earth highlights how much of LEO is accumulating numbers and mass of debris that are mathematically a ticking time bomb, and the global aerospace community must cooperatively work to manage the situation. The three primary means to control the debris collision risk in LEO are reflected in the three main chapters of our story:

💬 Conjunction Data Messages (CDMs) are the currency for timely and effective space traffic management. While our main character — the massive derelict rocket body — cannot execute collision avoidance maneuvers, most of the over 5,000 operational payloads in LEO can act on these warnings.

⚠️ Statistical probability of collision highlights the need to stop adding debris to LEO (i.e., debris mitigation).

🚀 The collision rate between clusters of massive derelicts amplifies the need for debris remediation (i.e., active debris removal).

The continual discussion of these facts and figures, we hope, will help motivate policymakers, regulators, space operators, and international military services to act responsibly to preserve the space environment for the generations to come. Tamara, a student from Williamston High School in Michigan and a member of the next generation, eloquently stated in a letter to LeoLabs: “The longer that the government waits to help solve this problem, the more debris there will be in orbit.”

The entire “collision risk story” can be captured in the figure below and is representative of the multi-dimensional debris collision risk challenges posed in LEO. Although complicated, these “stories” are important to tell because continual high-frequency monitoring and analytic characterization of conjunction dynamics in LEO can catalyze responsible actions by the global space community—and that’s exactly what we’re working towards at LeoLabs.

Notes: 

  1. So far in 2022, there have been over 20,000 close approaches in LEO where the PC has exceeded 1E-5.
  2. PC = 1-eλt where λ = collision cross-section (km2)*relative velocity (km/s)*spatial density (#/km3) and t is time (s)
  3. CR = (N2/2)*collision cross-section (km2)*relative velocity (km/s)*relative velocity (km/s)*time (sec)/Volume of altitude expanse of cluster (km3) where N is the number of objects in the cluster
  4. McKnight, et al, “Identifying the 50 Statistically-Most-Concerning Derelict Objects in LEO,” 71st International Astronautical Congress (IAC) — The CyberSpace Edition, Dubai, UAE, October 20 and McKnight, D., Dale, E., Bhatia, R., Kunstadter, C., Stevenson, M., and Patel, M., “A Map of the Statistical Collision Risk in LEO”, 73rd International Astronautical Congress, Paris, France, September 2022

This piece was written by LeoLabs Senior Technical Fellow Dr. Darren McKnight with support from LeoLabs’ Data Analytics Team. The featured image is Cosmos 389 ELINT by Brian W. McMullin, 1982 (Public Domain). Cosmos 389 was the first in a series of “ferret” satellites that performed Soviet-era electronic intelligence (ELINT) missions. This satellite was the predecessor to Cosmos 2082, the main character in our story.

Allow us to re-introduce ourselves: a behind-the-scenes look at our rebrand

Hi, we’re LeoLabs. You’ve probably heard of us. We’re the company building commercial space radars and services for LEO, changing the way we track and manage objects in space. We’ve been doing that since 2016.

(You’ve likely seen our free LEO visualization. No? Well, take a look. 🌎)

We started small, just four co-founders coming together with a passion for space safety and sustainability. We planted our roots in the heart of Silicon Valley, benefiting from the innovative, entrepreneurial spirit that infiltrates every coffee shop in town. We built our first fully owned and operated phased-array radar facility in Midland, Texas—the perfect spot for a burgeoning space company to prove its technology.

LeoLabs CEO and co-founder Dan Ceperley unveils our radar site in Midland, Texas in 2017.

We quickly grew as a team, as a company, and as a leader. How? By addressing the needs of the space industry with creative ideas built on decades of expertise in space safety and radar technology. Not to toot our own horn, but we’ve been pretty successful — and now, we’re embarking on the next phase of our journey.

Our evolution from a small startup to a scaling, global company

LeoLabs’ leadership answer questions from staff during our 2022 team retreat.

Like the title of this post suggests, we’re ready to re-introduce ourselves. For months, our internal brand and marketing team has been toiling away, flipping through color palettes, critiquing logo sketches, and digging through web designs.

And today, we’re thrilled to finally unveil our new brand identity which reflects our transition from a small startup to a scaling, global company. (We now have multiple offices, 100+ staff, and 6 independent radars across 8 countries and 4 continents!)

Don’t worry, we’re not saying goodbye to what made us great. This mission-driven rebrand simply embraces our growing role as an industry leader in today’s dynamic space era — while freshening up our look.

At its core, the new brand reaffirms our commitment to addressing our customers’ needs by increasing service levels and expanding our global radar network to maximize coverage of LEO. This rebrand underscores our mission of propelling the dynamic space era with superior information using the world’s first vertically integrated commercial space operations stack tracking LEO at scale — Vertex™.

(P.s. Exciting radar announcements coming soon. 👀)

An aerial view of one of our radar sites. We currently have four operational sites with more in development.

Here are the key elements of our brand evolution:

A logo fit for the future: Our new logo gives a nod to our legacy while also embracing a more modern design fit for the new space era. With a simplified “Earth” mark and streamlined, hand-kerned lettering, this new logo is modern and simple, as well as forward-thinking and intuitive.

Grounded, bold, sustainable colors: The new color palette was built to stand out. It incorporates a deep emerald shade of green and an uplifting mint green, alongside a fresh spin on the blue and gold found in our first logo. Within this palette, we lead with green, a color that signifies our connection to Earth — even if we’re busy looking up into space.

Retro futuristic visuals: A retro futuristic iconography and illustration style reflect our nod to the past while also embracing the future. Featuring innovations iconic in space exploration, like satellites and rocket bodies, these visuals aid in the explanation of our technology and ideas across our digital ecosystem. The brand will also be showcased through visually creative swag items and exhibit booths.

Unique, clear naming: Our newly rebranded product suite is as unique as the capabilities themselves, clearly differentiated from our competitors and anchored to our forward-thinking brand. Every LeoLabs-owned service or product has a name that follows a recognizable cadence: the “Leo” brand followed by a one-syllable word describing the product’s function.

An accessible, fluid website: Our new website serves as the digital foundation of our brand, encapsulating it in a symphony of color, iconography, and illustrations. It gives users an experience fitting for the space industry: where ideas move fast and clarity is prized.

A vibrant, data-driven content hub: To keep up with the rapid pace of change in low Earth orbit, we’ve created LeoPulse — a content hub which features analysis and insights that you can’t find anywhere else. From quarterly reviews to monthly thought leadership pieces, we’re “demystifying” LEO one data point at a time.

A mission statement that reflects our role in today’s space environment: “We exist to propel the dynamic space era with superior information.” We’re here to support innovation, and we’re driven by curiosity, passion, and know-how.

So, what do you think? We know it’s not New Year’s yet but it’s never too early for a little self-improvement, right?

Visit leolabs.space to just check out our new look, or take a peek at our social channels.

Until next time, ad astra! ✨

Planning for the inevitable: a guide to disasters in low Earth orbit

Short on time?  Listen to this article on-the-go. 

In the opening credits of the 1998 blockbuster, Armageddon, an asteroid strikes Earth, causing fire to engulf the planet. “It happened before,” Charlton Heston warns, “It will happen again. It’s just a question of when.”

Unlike 99% of this movie, Heston isn’t exactly wrong. Scientists believe an extinction-causing asteroid hit Earth almost 66 million years ago. They also believe that another deadly asteroid strike is possible. That’s why many scientists, including my co-founder at LeoLabs (and former NASA astronaut) Ed Lu, study asteroids and develop protection measures. We got a glimpse into this work during NASA’s Double Asteroid Redirection Test (DART) earlier this year. Lucky for us, it was a success.

Heston’s iconic phrase is not just applicable to asteroid strikes. Throughout history, the inevitability of disasters, from recurring events like hurricanes to rare events like pandemics, has led us to prepare for them as best we can. I believe disasters in low Earth orbit (LEO) should be approached no differently.

The inevitability of a disaster in low Earth orbit

The traffic in LEO is growing rapidly, particularly in lower altitudes ideal for large constellations, CubeSats, and crewed spaceflight. The sun-synchronous orbits are also a popular destination for earth imaging missions in LEO.

Across LEO, thousands of pieces of space debris reside in clouds of fragments and clusters of massive derelicts. This grim reality means that collisions are not a question of if but when. To prepare for this inevitability, we must understand what the dangers are and the threat level. That’s my job. My primary concern is protecting operational objects in space, like satellite constellations, which have become critical to daily life. That’s why my team and I work tirelessly to not only monitor the risks in space but to also characterize them.

Every industry has its bad days, including space. Rather than ignore them, the best response is to anticipate and prepare for them. Towards this effort, I’ll discuss four types of potential disasters in LEO below, these include:

  1. Operational payload on catalogued object collision
  2. Dead object on dead object collision 
  3. Object colliding with lethal, small debris
  4. Operational payload attacked by an adversary

— Skip to: How to prepare and respond to an in-orbit disaster —

Operational payload on catalogued object collision

An operational satellite colliding with a catalogued object, such as another operational satellite or a trackable, non-operational object, is possible. Thankfully, this scenario is the easiest to avoid if the operational satellite is maneuverable. Satellite owner-operators can be notified of an upcoming conjunction in the days leading up to the event and act on that information. If the secondary object is non-maneuverable or non-operational, the owner-operator can decide how they want to maneuver. However, if the secondary object is another maneuverable satellite, the two owner-operators should coordinate.

This disaster scenario has occurred in the past when space situational awareness information was not as available as it is today. In 2009, an active Iridium satellite collided with an inactive Russian communications satellite. As a result, The U.S. military’s Joint Space Operations Center re-added the Iridium constellation to its daily conjunction assessment procedures and eventually expanded to cover all active satellites. In addition, the U.S. Strategic Command created a new program to encourage detailed information-sharing regarding the location and risks of objects in orbit. Today, that information is found in a publicly accessible platform managed by the Combined Space Operations Center and the 18th Space Defense Squadron.

While this disaster scenario is still a possibility, it’s less likely thanks to these changes as well as more advanced tracking technologies — like LeoLabs phased array radars and collision avoidance services — and operational capabilities from satellite owner-operators.

Dead object on dead object collision

Here’s what keeps me up at night: a collision between two massive dead objects in LEO. Why? Because this scenario is largely out of our control and fairly likely. On average, there’s one noteworthy conjunction event between two objects in LEO every minute. 75% of the most consequential events (i.e., those that will create the greatest number of fragments) are between two derelict objects.

When two objects collide in space, no matter the orbit, the number of fragments produced is proportional to the mass involved. The breakup of the 850 kg Fengyun 1C satellite in 2007, for example, resulted in more than 3,500 fragments larger than 10 cm. Any collision is a bad day, but if two massive dead objects collide in LEO, the result would be catastrophic. The collision would disperse debris across hundreds of kilometers in altitude and potentially impact multiple constellations, creating a ripple effect of dangerous collisional encounters. A rapid escalation of these types of events is indicative of what the beginning of the Kessler Syndrome would look like.

While this worst-case scenario hasn’t happened yet, we’re due for a collision between two massive derelict objects, according to observations made by my colleague Dr. Darren McKnight and his team. (More details to come in future editions of LeoPulse.)

Object colliding with lethal, small debris

Lethal, small debris (i.e., sized 5 millimeters – 10 centimeters) are numerous in LEO and can have a damaging effect on both operational and non-operational objects. A collision with a 10 cm debris fragment, for example, could cause an operational satellite to break up completely. While a collision with fragments between 1 to 10 cm would likely cause mission-terminating damage and a collision with a 5 mm to 1 cm debris fragment would likely cause mission-degrading damage. Any size fragment above a few millimeters is likely lethal to astronauts. Unfortunately, this smaller debris is not yet tracked, which means we’re unable to effectively mitigate the risks from it. It’s not all bad news though, we’re actively working on a solution at LeoLabs.

In 2021, the world witnessed the effects from this type of debris when a small fragment tore a 5 mm hole in Canadarm 2’s thermal blanket that was attached to the International Space Station. While the robotic arm remains functional, the incident was a clear indication of the risks posed by even a millimeter-sized debris fragment. Put simply, what we can’t see has the potential to kill us.

Operational payload attacked by an adversary

The United States, India, Russia, and China have proven their ability to physically destroy a satellite by testing anti-satellite weapons (ASAT). These tests have resulted in thousands of pieces of space debris in LEO. Fragments from the 2021 Russian ASAT test, for example, continue to cause dangerous conjunctions: we observed ~3,000 in August alone. While there is a US-led movement to ban kinetic ASAT tests on orbital targets, the risk remains. There is also the possibility of a cyber-attack which could render a satellite non-operational. Russia’s threats against Space X’s Starlink satellites during the war in Ukraine, for example, have illustrated how real this risk is.

How to prepare for and respond to an in-orbit disaster

With today’s technology, it’s easier to prevent a disaster in LEO than it is to clean up after one. With this in mind, preparatory actions should reduce the likelihood of a disaster and respond quickly to one. Below, I’ve listed a few necessary actions along with some of the activities that are already underway across the industry, these include:

  • Remove old debris
  • Prioritize collision avoidance
  • Report regularly
  • Strategize for survivability
  • Create a response framework
  • Publicize threatening actions

Remove old debris

Tracking and monitoring debris is not enough to effectively prevent a disaster; we must invest in debris removal technologies and missions, and fund research into cleaning up small debris fragments. Thankfully, we’re on the right path. In 2020, the European Space Agency (ESA) awarded a contract to ClearSpace for the world’s first active debris removal (ADR) mission. This follows multiple ADR demonstrations over the last few years by SSTL, Astroscale, and others. In addition, new technologies are under development that will enable the rapid de-orbiting of satellites. Regulatory measures are also addressing the space debris issue. Members of the U.S. Congress recently introduced the ORBITS Act aimed at funding the development of ADR technology, and the Federal Communications Commission (FCC) recently changed the 25-year rule for de-orbiting satellites to a 5-year rule.

Prioritize collision avoidance

We should prioritize enabling day-to-day collision avoidance maneuvers for active satellites to avoid dangerous conjunctions. Many satellite operators have collision avoidance as part of their operational routine, but this should be enhanced with more tracking infrastructure and a focus on smaller debris.

Report regularly

Reports should be published on the risk of collisions so that operators are aware of changes in the risk environment and regulators can update policies. This includes internal assessments by operators identifying the risks facing their critical satellite assets and reports by regulatory bodies highlighting changes in the risk environment.

Strategize for survivability

Operators building and maintaining constellations should think about how they can ensure the survivability of their system if an accident occurs. This can be achieved through increased impact tolerance, on-orbit servicing, or “shelter in place” protocols, which occur when a satellite reduces its cross-sectional area to reduce the probability of collision. Ongoing improvements to spacecraft design are  promising. On-orbit servicing, for example, is moving into the mainstream with the launch of Northrop Grumman’s SpaceLogistics vehicles.

Create a response framework

If a disaster occurs, there should be a standardized framework that lists necessary actions to be taken on the part of operators and regulators, including identifying the object(s) involved, cataloging new debris, and possibly identifying necessary changes in traffic patterns.

Publicize threatening actions

If an ASAT test occurs, for example, that information should be shared publicly, along with a characterization of the collision risk that the event created. This information is important for deterring aggressive actions, informing diplomatic responses, and setting boundaries between acceptable and unacceptable behavior.

— Return to: Types of disasters in low Earth orbit —

Mitigation through planning

In a sense, Earth’s orbits are like the oceans, forests, and deserts. They are environments that we both depend on and that need our protection. However, the orbital environment differs in one key respect: we’re building it and thus have the chance to preserve it for the good of everyone.

Unfortunately, like that giant asteroid hurtling towards Earth in Armageddon, a disaster in LEO is approaching, it’s just a matter of time.The impact can’t be dismissed by saying, “that’s not in my country or my city,” because a collision on the other side of LEO will arrive in your satellite constellation’s backyard 45 minutes later. That’s why we must collectively and actively plan for all possible scenarios. Whatever happens up there will affect all of us down here.

More of a visual learner? We’ve got you covered.  Download this infographic.

Don’t forget! You can   listen to LeoPulse on Spotify


 

And that’s all for now folks!

Stay tuned for the 3rd edition of LeoPulse coming out in mid-December which will feature another 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. Have a suggestion about what we should cover? Let us know by emailing our editor Victoria Heath at vheath@leolabs.space with the subject line: LeoPulse suggestion.

Ad astra! 

Note: The findings shared in this report and infographic are derived from the hundreds of thousands of data products LeoLabs’ global network of phased array radars collects daily.

What’s up in LEO? Quarterly insights from June to September 2022

Short on time?  Listen to this article on-the-go. 

In 2019, there were 800 functional satellites in low Earth orbit. Now, there are over 5,000.

That exponential growth makes even the most seasoned space veteran say, “Wow.”

And remarkably, the industry is just getting started.

Understandably, this is causing some to ask, “Are we running out of space in space?” This fear is compounded by the number of debris left behind during the previous six decades of space operations. It’s true: we’re in a uniquely challenging collision risk environment. However, while this is certainly a cause for serious reflection, it’s not a cause for panic. This momentous period in the space economy doubles as a rare opportunity to examine how the previous space era mixes with the new, and to use innovative thinking and collaborative problem-solving to preserve LEO for future generations.

Demystifying low Earth orbit, one data point at a time

To combat fear and confusion, we must first address the feeling of mystery around LEO and the estimated hundreds of thousands of space objects (and debris) that fill this seemingly shrinking realm. And that’s exactly what we aim to do.

With help from the team of analysts and engineers at LeoLabs, we’ll use the data collected by our global network of phased array radars to “demystify” LEO for you. Every quarter, we’ll review what’s happened and help answer the questions wracking your brain, like: “What’s more dangerous to operational satellites today? Constellations or debris?” and “Which regions have the greatest collision risk now? Or might in the future?”

As you read through LeoPulse, we hope a few aspects of the solutions necessary for tracking and managing the growing traffic in LEO become clearer. Just like safer driving or flying here on Earth, safe operations in LEO requires responsible behavior, sound analytic assessments, transparent communication and effective regulation.

From the ground up: an in-depth look at the traffic in LEO from June to September 2022

Moving forward, our quarterly reports will examine three primary components of the LEO population: “Clouds,” “Clusters” and “Constellations,” with a bonus section called “Bad neighborhoods.” Each of these sections will be updated with data and insights relevant to satellite operators, regulators, and others concerned with STM and SSA.

— Skip to: Clouds | Clusters | Constellations | Bad neighborhoods —

Clouds

Over 250 objects have fragmented in LEO over the last 60 years. These events create “clouds” of fragments that spread rapidly across large volumes in space. Today, three major collision-induced clouds dominate the LEO environment: Fengyun 1C, COSMOS 1408, and COSMOS 2251. Fragments from these events spread hundreds of kilometers in altitude and likely contributed tens of thousands of additional lethal but currently non-trackable fragments (smaller than 10 cm).

From June to September 2022, the number of COSMOS 1408 debris fragments in orbit continued to decrease (from ~600 to ~500) because of atmospheric drag cleansing them from orbit. This decrease, however, didn’t lead to a decrease in monthly dangerous (PC > 1E-6) conjunctions: ~2,500 occurred in June and ~3,000 were monitored in August. This highlights the fact that collision risk in LEO is dependent on many factors beyond the number of objects in orbit. In the past, many of the COSMOS 1408 conjunction events occurred in bunches (described as “squalls” by Dan Oltrogge of COMSPOC). We observed a squall in mid-August, which led to the conjunctions mentioned above.

Overall, during this last quarter, we observed that out of the ~107,000 high-PC encounters in LEO, ~47,000 involved fragments from ten clouds of debris that have more than 150 fragments still in orbit. Put simply, roughly 45% of dangerous events observed during this period involved remnants from just ten breakup events.

Key takeaways:

  • Three collision-induced clouds dominate LEO: Fengyun 1C, COSMOS 1408 and COSMOS 2251
  • COSMOS 1408 debris fragments decreased from ~600 to ~500 due to atmospheric drag. However, the number of dangerous conjunctions involving COSMOS 1408 debris increased due to an increase in operational satellites
  • Roughly 45% of dangerous events observed involved remnants from just ten breakup events 

Clusters

During the first 45 years of the space age, massive derelict objects — from spent rocket bodies to non-operational payloads — were abandoned, creating a ticking time bomb of debris-generating potential. They currently account for nearly 75% of the total mass in LEO. We refer to them as “clusters” because these massive derelict objects are often abandoned in large numbers in similar orbits.

In a recent study led by LeoLabs, we identified the top 50 statistically-most-concerning objects in LEO. While 40 of these objects were abandoned before 2001, the Chinese government has abandoned four rocket bodies in the last decade alone. However, the most populous family of rocket bodies are the 285 Russian SL-8 rocket bodies littered throughout LEO. Over the last quarter, there were nearly 4,000 dangerous conjunctions involving at least one SL-8 rocket body and 41 conjunctions involving two SL-8 rocket bodies.

There were also 16 conjunction events involving two massive derelict objects (typically large, abandoned rocket bodies and defunct payloads) that totaled over 15,000 kg in combined mass. If any one of these dangerous crossings resulted in a collision, it would likely generate well over 15,000 cataloged fragments — nearly doubling the current catalog. Unsurprisingly, we observed that 13 of these events involved two SL-16 rocket bodies. For years they’ve been recognized as the most troublesome cluster in LEO because 18 of them reside within a 40 km altitude range.

Key takeaways:

  • 75% of the total mass in LEO is currently made up of objects abandoned primarily during the first 45 years of the space age 
  • The most populous family of rocket bodies are the 285 Russian SL-8 rocket bodies; nearly 4,000 high-PC conjunctions involved an SL-8 rocket body 

Constellations

Operational satellites are deployed more and more in large constellations, driving up space traffic management demands and collision avoidance needs. The locations of these deployments vary widely. Currently, nearly 25% of objects in LEO are operational payloads deployed in lower altitudes (i.e., below 1,300 km).

It should come as no surprise that SpaceX’s Starlink remains the largest constellation in LEO. In the last quarter alone, the constellation grew by several hundred to total just over 3,000 operational satellites. The spatial density (i.e., number of objects per cubic kilometer at 2.5E-7) is now the largest at the Starlink altitude (~550 km) than anywhere else in LEO.

At first glance this may seem concerning because spatial density is used to estimate the likelihood of a collision for uncontrolled objects. In the case of operational constellations, however, this is a bit misleading due to the synchronization of active, agile, and station kept satellites, which are distinctly different than a cloud or cluster of debris. It’s like considering the likelihood of a collision with a marching band on a football field versus a chaotic swarm of students after a big win.

Let’s look at the altitude of 840 km, for example. We consider this a “bad neighborhood” (more on that below) because while its spatial density is just 20% of the Starlink constellation (5.7E-8), it consists of a quagmire of breakup fragments, massive rocket bodies, and non-operational payloads. The mass density (number of kilograms per cubic kilometer) for this altitude is also a factor of three smaller compared to the Starlink altitude. What makes this altitude much more dangerous, however, is the fact that the derelict objects have no intent or capability to avoid collisions — constellations do.

Key takeaways:

  • Nearly 25% of objects in LEO today are operational payloads deployed in lower altitudes (i.e., below 1,300 km)
  • The spatial density at the Starlink altitude (~550 km) is now the largest than any place else in LEO, but spatial density is not an accurate measurement of collision risk between members of constellation

Bad neighborhoods

Let’s keep our attention on the “bad neighborhoods” of LEO. The prototypical “bad neighborhood” is 800 km to 900 km. This region consists of a mix of several significant breakup events and hundreds of abandoned derelict objects that together create the greatest debris-generating potential in LEO. However, the region from 950 km to 1050 km is also littered with hundreds of derelict objects, including ~160 SL-8 rocket bodies along with their ~160 payloads deployed over 20 years ago. There were 1,400 high-PC conjunctions involving these rocket bodies in the last quarter alone. Earlier in 2022, the riskiest conjunction event of the year occurred in this same “neighborhood” between COSMOS 2334 and COSMOS 2315, two non-operational payloads deposited in orbit over 25 years ago. The event between these two payloads occurred at ~1,000 km with a miss distance of 15 m and a probability of collision (PC) of 3%. Typical PC values of concern are much, much smaller than this, so that one made us sweat a bit.

Key takeaways:

  • The region between 800 to 900 km has the greatest debris-generating potential in LEO due to Chinese fragments, abandoned Russian rocket bodies, and a combination of nonoperational payloads and fragments of American origin

Keep your eye on the sky: what’s coming up in LEO

What can we expect in the next quarter? Unsurprisingly, more satellites will launch into LEO. This includes satellites from SpaceX and OneWeb, as well as the Joint Polar Satellite System 2 (JPSS 2) by NASA and NOAA scheduled for early November.

In terms of legislative and regulatory activities related to LEO, the United States government is asking for support to propose a resolution at the United Nations General Assembly (UNGA) for states to commit “not to conduct destructive direct-ascent anti-satellite missile (ASAT) tests.” Prepare to see more discussion on this topic during the UN’s next Open-Ended Working Group on Space Threats (OEWG) meeting in January. Finally, in the last quarter, Japan, Germany, and New Zealand joined the US-led initiative to impose a self-ban on ASAT missile tests that create orbital debris. At the time of writing, both South Korea and United Kingdom have also joined the initiative, bringing the total number of countries to seven. Expect to see more countries follow suit in the coming weeks.

In addition, we expect to see more discussion (and some pushback) following the adoption of the Federal Communication Commission’s order to set a “five-year rule” for disposing satellites in LEO. It’s likely that we’ll also see potential movement from other governments with similar guidelines. This may be particularly true in the United Kingdom, which recently made significant movement towards demonstrating active-debris removal in orbit by awarding two Phase B demo contracts to ClearSpace and Astroscale. For more on why we think the “five-year-rule” is a good step forward, check out this WIRED article.

Finally, when it comes to Space Traffic Management (STM), you may have missed the agreement signed by the US Department of Defense and Department of Commerce in September to work together to achieve Space Policy Directive (SPD) 3. This directive calls for the development of a new national STM service managed by a civil government agency. As part of this initiative, LeoLabs was awarded a contract to help support the development of a US, civil-led STM prototype.

— Return to: Clouds | Clusters | Constellations | Bad neighborhoods —

More of a visual learner? We’ve got you covered.  Download this infographic.

 

Don’t forget! You can also  listen to this article below or on Spotify.


 

And that’s all for now folks!

Stay tuned for the 2nd edition of LeoPulse coming out in mid-November 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. Do you have suggestions about what we should cover in the next quarterly review (scheduled for January 2023)? Let us know by emailing our editor Victoria Heath at vheath@leolabs.space with the subject line: LeoPulse suggestion.

Ad astra! 

Note: The findings shared in this report and infographic are derived from the hundreds of thousands of data products LeoLabs’ global network of phased array radars collects daily.

Photo credit: Matthew Shouppe (Senior Director  of Insights & Partnerships, LeoLabs)

Part III — Cosmos 1408 Breakup Observations One Month Later

It’s now been five weeks since the Russian ASAT demonstration that struck the Cosmos 1408 satellite, causing enormous amounts of new space debris to be generated in a heavily utilized altitude band in Low Earth Orbit (LEO).

In Part II of our analysis on this event, we considered the plausible explanation that the Cosmos 1408 destruction was caused by a non-hypervelocity impact, possibly even coupled with some explosive charge. The table below summarizes the two ends of the spectrum as discussed previously (hypervelocity vs. non-hypervelocity)— the actual event is probably somewhere between these two extremes which will confound a high confidence assessment of the impact initial conditions.

We also commented that the result may have been a less destructive event — fewer, but larger, new debris fragments — compared to a pure hypervelocity impact (that exceeded the 35–45 J/gm threshold for catastrophic breakup).

In the weeks following this event, LeoLabs has taken a two-fold approach to continue collecting data on the new fragments. First, our automated catalog tracking system matches that of the 18th Space Control Squadron, whereby we routinely track new RSOs in the LEO regime as they are added to the public satellite catalog. As of this writing, the number of Cosmos 1408 debris fragments in our system is close to 500, and will certainly continue to rise in the coming weeks and months. Our 3D LEO catalog visualization offers a daily glimpse at this, here:

Our operational platform schedules radar observations for each fragment, collects measurement data on each radar pass, processes it in our orbit determination system to generate state vectors and ephemerides, and screens these ephemerides against our customers’ satellites to generate Conjunction Data Messages (CDMs) to alert satellite operators of any dangerous close approaches.

Second, LeoLabs’ Data Science team members have been monitoring the radar cross-section (RCS) values of the resulting debris through collection of additional observation data. The 30-day average for the RCS of Cosmos 1408 before the event was ~9 m². The table below summarizes the RCS values for the largest nine pieces detected by LeoLabs and their estimated masses.

Estimated mass for large Cosmos 1408 fragments

These larger objects are consistent with large appendages of the Cosmos 1408 spacecraft (four antennas, two solar arrays, and several booms) that likely would have been left intact (or largely intact) from this event.

The largest object was assumed to have an area-to-mass ratio of 0.01 m²/kg (i.e., basically an intact portion of the satellite) while for the other fragments an area-to-mass ratio of 0.075 m²/kg is applied (i.e., typical for chunky debris fragments). Using these conversions, the mass of these objects is estimated to be ~400 kg, or roughly 23% of the total mass of 1750 kg*.

While we have not compiled a complete RCS distribution for the debris resulting from this event, the preliminary analysis shows that the average RCS for hundreds of fragments being characterized is ~0.050 m², though there is clearly a range of RCS values. These smaller fragments will likely have a larger area-to-mass ratio than the larger chunky fragments.

Using the typical value for trackable debris fragments of 0.10 m²/kg produces a total of ~2,700 more fragments to account for the additional 1,350kg (total mass estimate from debris would equal the pre-event estimate of ~1,750 kg).

It should be noted that the smallest fragments generated in a breakup event only need a small amount of mass to represent a large number of fragments. For example, 1,000 one cm fragments (i.e., solid spherical objects) made of aluminum amount to a little over 10 kg. Similarly, if the average RCS for the smaller debris was closer to 0.025 m², then the total number of trackable fragments would grow from ~2,700 to ~4,000.

This highlights the sensitivity of the impact conditions on the debris liberated, as hypervelocity events typically create many more fragments smaller than 10 cm than do explosions or non-hypervelocity impact-induced fragmentations. The real question is, how many of these smaller (<10cm) fragments were created, since they still constitute mission-terminating collision risks but are currently not reliably cataloged. (LeoLabs will start to catalog previously untracked sub-10cm debris starting in 2022.)

In conclusion, further analysis continues to lend credence to a non-hypervelocity impact encounter. As stated previously, this just means fewer fragments but ones that are likely longer-lived (due to their larger mass) than “typical” collision-induced fragments. However, much analysis is still ahead of us. As we refine the RCS values for this cloud of debris, we will report our findings as a means to better understand what occurred on November 15 and, more importantly, to characterize the long-term mission-terminating collision hazard posed by this event to satellites in LEO.

While it is tempting to try and reconstruct the exact conditions of the breakup, we also don’t want to focus all our efforts here because the end result of the event is what’s most important — substantially increased risk for many operational satellites.

The statistical probability of collision for satellites with mission-terminating debris in the 300–800km altitude range has likely doubled due to this event, and will remain high for many years.

The only way to mitigate this risk is to catalog these fragments, and track them accurately and frequently to produce actionable conjunction alerts for satellite operators. LeoLabs is already doing this to support our customers, and will only increase the cadence and fidelity of tracking by deploying multiple additional S-band radars around the world over the next 12–24 months.

It should be noted that in our previous analysis we stated a 2,200 kg mass for the Tselina-D, but upon closer review of sources the mass of the satellite is likely 1,750 kg as stated by the manufacturer KB Yuhznoe. (Thanks to Jonathan McDowell for the note on Twitter :)) No matter how you slice it, this target was at least twice as massive as Fengyun 1C, the target for the Chinese ASAT test in 2007.

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