Introducing LeoLabs Collision Avoidance

8 min readMay 13, 2020

For the past year and a half, we’ve been hard at work maturing our capabilities to accurately identify and monitor potential collisions in LEO. We activated our internal conjunction screening service in early 2019, a first of its kind system that performs a continuous full catalog search for potential collisions and stores hundreds of thousands of conjunction data messages (CDMs) to our cloud-based servers every day. We continued to refine our system, study the data, and even publicly report some of the high risk events our system detected such as the IRAS/GGSE-4 close approach of January 2020.

Now, we are ready to offer these same advanced risk monitoring capabilities to satellite operators around the world. We’re excited to release LeoLabs Collision Avoidance, our commercial suite of services for operational safety of flight. This is the first time a single commercial company has been able to offer end-to-end services for operators in LEO; from radar observations of space debris to web analytics.

Satellite operators now have a dedicated commercial platform backed by its own worldwide radar network to aid them in safely and economically operating their spacecraft.

So what exactly does this service do, and what’s included? In this post, we’ll take an in-depth look at all the features.

Streaming Conjunctions

The core component of LeoLabs Collision Avoidance is our Streaming Conjunctions service. Subscribing users can now receive real-time “streaming” conjunction alerts for their satellites. What’s unique about this is not just the alerts, but how they’re delivered. Timing is crucial for these events, and our system sends the alerts the instant they’re available in our system. (Picture your Twitter feed updating in front of you; just sit back and watch the new messages come in.) This results in a significant increase in the quality and quantity of conjunction data available to operators earlier in an event, to make informed decisions on whether or not to maneuver their satellites.

In addition to LeoLabs screening our own internally generated ephemerides for user satellites against the rest of our object catalog, we also let our users upload their own operational ephemerides and we will use those as well. Many operators have very high accuracy telemetry, such as on-board GPS with precision orbit determination, in addition to incorporating planned maneuvers that we at LeoLabs alone cannot know in advance. For this reason, it’s advantageous to screen operator ephemerides against our catalog continuously. This will also report any conjunctions detected between two operator satellites across organizations. The more users contribute their operational ephemerides to our data platform, the better it gets.

Miss Distances from independent data sources shown in a LeoLabs Conjunction Analysis Report

This example above shows real data from a conjunction event where we had an operator ephemeris provided to us, and we clearly see the strong correlation between the two separate data series showing the computed miss distance for this event.

On-Demand Ephemeris Screenings

What if you need to test multiple maneuver profiles for mission planning, to make sure they don’t generate potentially risky conjunctions? How can you quickly know with confidence that your planned collision avoidance maneuver won’t take you out of the way of one object but increase risk of colliding with something else?

Now with LeoLabs Collision Avoidance, you can screen your own ephemerides instantaneously against the full LeoLabs object catalog to check for conjunctions.

There’s no human approval or task execution needed on the LeoLabs side; just submit the request and CDMs will be returned automatically based on your own customized screening parameters within 30 seconds. Users can automate this service and deploy it at scale; test dozens or hundreds of ephemerides for a full constellation programmatically and fold it into your operational workflow.

Summary results of an example on-demand ephemeris screening

Enhanced Secondary Object Access

One big pain point in satellite operations until now has been the lack of access to high quality, timely data on the secondary object in conjunction events (i.e. the other object that might hit your satellite). These secondary objects are sometimes other operational satellites, but are more often random pieces of debris, rocket bodies, or defunct satellites that have been non-operational for years or decades.

LeoLabs Collision Avoidance provides users with access to the orbital states and ephemerides with full covariance matrices on all secondary objects reported in our conjunction events. You can use our conjunction risk assessment tools included with this service (described below), or if you have your own existing analysis tools and just want to ingest our data for the secondary object, you can do that too.

Additionally, users now have the ability to task our radars directly for increasing tracking prioritization on secondary objects of interest. This can be manually done at any time by the user, but we do it automatically for all high-risk events we detect for our users’ satellites.

User menu for submitting a tasking request for increased radar prioritization for an object of interest

Users also have direct insight into our radar observation schedules; know exactly when to expect your next set of measurements for the secondary object and which radar it will come from, so you can plan accordingly.

APIs and Web Analytics Tools

To meet the needs of tomorrow’s largest constellations, we built LeoLabs Collision Avoidance as a fully automated suite of web services that performs incredibly well at scale. We accomplish this by utilizing a system architecture built on modern RESTful APIs that provide a variety of data queries and endpoints for task execution and data uploads/downloads. The result is a performant, lightweight set of calls that users can integrate into their operational mission workflow to efficiently send requests and receive data they need for making timely decisions. Read our full API documentation here:

Additionally, satellite operators and analysts don’t just need good data — they need robust tools to process, analyze and intuitively understand the data. LeoLabs Collision Avoidance provides a full suite of web analytics tools and resources on our user website ( Tailored conjunction analysis reports aggregate all CDMs created for a single event and display them together, updating dynamically as new data is available from multiple data sources.

Summary section of a LeoLabs Conjunction Analysis Report between a rocket body and debris object

These reports provide detailed information on event risk, including miss distances with uncertainties, probabilities of collision with sensitivity weightings, and a variety of other interactive data plots with tracking and trending information for both objects involved. Users can also generate pre-formatted PDF conjunction analysis reports to send to their teams, management, or other satellite operators.

Real-time 3D visualization of a satellite operator’s upcoming conjunctions

For enhanced situational awareness, operators can now also view all of their upcoming conjunctions in a real-time 3D feed they can deploy operationally, with intuitive search and slider tools for filtering conjunctions by object, time, miss distance, and probability of collision. Users can view conjunction animations, as well as conjunction evolution for individual events over an eight-day screening period.

3D animation of a real conjunction between an operational satellite and piece of debris

At LeoLabs, we believe keeping tabs on your satellites should be as easy as opening Google Maps on your phone and getting directions to the grocery store.

Our web interfaces are clean, simple and modern. No more clunky desktop software and steep learning curves — just get the data you need delivered straight to you so you can focus on your mission. In these trying times when operations teams are forced to work remotely, be able to responsibly monitor your fleet’s safety of flight from home, even on your phone.

External Data Ingestion

When it comes to satellite operations, there is no one-size-fits-all approach. That’s why we designed LeoLabs Collision Avoidance to work as a stand-alone service, or as an augmentation to existing operational systems. One way we achieve this is by offering the ability to ingest users’ existing conjunction alerts into our own platform.

Currently, the US Air Force 18th Space Control Squadron (18 SPCS) provides a valuable public screening and conjunction notification service to satellite operators. We often get asked how our LeoLabs service relates to this, and the answer is that the two are completely complimentary. Use both!

We happily encourage our customers to continue using the alerts provided by 18 SPCS to have even more data for conjunction event monitoring, so we designed LeoLabs Collision Avoidance to ingest these alerts into our platform and combine them with our own data.

Since both LeoLabs and 18 SPCS generate the same data product for conjunction alerts (CDMs) in the same standardized formats, it’s easy to combine the two data sets into a single consolidated reporting interface in the LeoLabs data platform. Now, operators can view both sources of conjunction screenings and alerts (LeoLabs and 18 SPCS) which themselves are created from up to three independent sources of ephemeris data (LeoLabs catalog, 18 SPCS catalog, and operator ephemerides). This multi-source data aggregation results in the most complete solution for reliable conjunction risk information available to operators from any service available today.

LeoLabs Collision Avoidance — system architecture for multi-source data aggregation

As an example, operators currently using only alerts from 18 SPCS can commonly expect a 50–300% increase in the number of CDMs they receive by adding LeoLabs Collision Avoidance to this workflow.

This allows more high quality data to be delivered days earlier, so that maneuver decisions can be made well in advance.

This consolidated solution also eliminates the issue of having piecemeal data from different sources, delivered in different formats, being combined into different tools that have trouble working with one another and have their own separate maintenance costs. All data and analytics tools are now available in a single place, accessible from any location.

Scaling Up

Over the next 24 months, we’ll be adding additional radars to our global network and significantly expanding the size of our object catalog to include previously untracked small debris. With each new radar we add, the features in LeoLabs Collision Avoidance will follow suit with even greater tracking accuracy, revisit times, and conjunction predictions. Our expanded radar network should allow for nearly hourly conjunction updates on an estimated catalog of hundreds of thousands of objects.

Contact us today for an evaluation of the LeoLabs Collision Avoidance system; we’ll track risk on your satellites free for 30 days. Use our tools and judge for yourself. Reach out to us at or request an account at

Written by Matthew Shouppe, LeoLabs Director of Commercial Space




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