As the number of satellites in LEO continues to grow exponentially, when it comes to a satellite’s location, sharing is caring.
Varying predictions have the satellite population in LEO increasing by two- to six-fold by the end of this decade. That is a phenomenal growth rate that will provide an abundance of new services and capabilities here on Earth, but it is not without consequences. More sats zooming around means more collision warnings and more maneuvering in orbit—something companies could help avoid by sharing precise location data with other operators.
Traffic jam: Orbital congestion is a growing area of concern. Today, there are 10,000+ operational satellites in LEO, plus 3,500 decommissioned satellites and millions of pieces of debris. With so many objects in Earth’s orbit operated by a diverse group of governments and commercial players, space traffic coordination is becoming significantly more complex.
It’s made even harder by the lack of real-time, high-accuracy data on satellite operational orbits and their planned maneuvers—something companies possess but often refuse to share. As of today, only 3-4% of global satellite operators openly share their ephemerides with the industry.
Growing risk: The frequency of conjunctions is increasing significantly. In a typical 72-hour period, Kayhan Space tracks between 120,000 to 150,000 conjunctions, or near-collisions, with approximately half of these occurring between two operational satellites (as opposed to debris). Several thousands of these conjunctions occur with a miss distance of less than half a kilometer—less than one tenth of a second in orbital speed.
Pressure on operators: This high rate of conjunctions takes its toll on both the satellites and their operators. Unplanned maneuvers use up the satellite’s thruster fuel and require the attention of a potentially under-resourced mission operations team.
One example: SpaceX’s Starlink constellation performed ~50,000 collision avoidance maneuvers in just the first half of 2024. That amounted to 275 maneuvers per day.
The limits of public tracking: Ephemeris is the precise data set that describes a satellite’s position and velocity over time. It is significantly more accurate than the two-line element (TLE) sets generated by the Space Surveillance Network (SSN) that are made publicly available through Space-Track.org (which is transitioning to the Office of Space Commerce’s Traffic Coordination System for Space, or TraCSS).
While the SSN also generates ephemerides, this data still has certain limitations. These ephemerides may be less precise than an operator’s own tracking data, and the SSN does not track commercial satellite maneuvers in real time or have access to most of the planned maneuvers. Unannounced maneuvers can result in higher uncertainties for SSN solutions, artificially inflating the calculated probability of collision.
Onboard data: Most modern satellites are equipped with GNSS receivers, among other onboard sensors, which can create precise ephemerides that are accurate to within two to five meters. Advanced GNSS processing techniques can further refine this accuracy to the centimeter- to decimeter-level, making it significantly more precise than what is calculated by the SSN, which at times may be accurate only to a few tens of kilometers.
Onboard sensors also allow for real-time updates with minimal latency. If this high-precision ephemeris data—along with planned maneuvers and covariance data—was shared broadly across the satellite industry, it could substantially reduce the risk of conjunctions. In certain cases, operators could potentially eliminate the need for conjunction maneuvers, significantly reducing their operational costs and increasing the satellites’ lifespan.
Why aren’t satellites already sharing this information?: Many satellite operators have been reluctant to share their ephemerides because they consider the data to be proprietary. But this concern ignores the more substantial risk of a collision in orbit, as LEO becomes increasingly crowded. The cost of losing a satellite outright or incurring significant damage due to a collision is far more urgent.
Frequent conjunction maneuvers also interrupt normal operations, reducing revenue and using up limited thruster fuel, ultimately reducing the lifespan of these important assets.
Additionally, third-party space situational awareness (SSA) providers can utilize shared ephemerides and planned maneuvers to perform analyses without releasing the information publicly.
How to move forward: Satellite operators need to work more closely with public and commercial SSA and Space Traffic Coordination (STC) services to securely share their ephemerides and planned maneuvers at a machine-to-machine level. This robust information sharing will provide a more complete and near real-time understanding of the orbital environment, dramatically reducing the risk of collisions.
While TraCSS is expected to come online later this year, it will offer only a portion of the necessary data and services. The commercial sector will play a critical role in filling these gaps, and satellite operators need to actively engage with these providers to mitigate orbital risks effectively.
Araz Feyzi is the CTO and cofounder of space traffic management company Kayhan Space.
