Make Way for Satellites

Subheadline

Space traffic coordination system helps make sure satellites stay in their lane

As of 2024, there are more than 45,000 human-made objects orbiting Earth, and these are just the ones we can track. With so many crowded orbits, and hundreds more satellites being launched every year, close approaches are inevitable. And with the increasing importance of satellites to modern infrastructure, it’s imperative these approaches don’t result in any collisions that would disrupt the important tasks being performed or cause debris that could impair other spacecraft.

Right now, the U.S. Space Force tracks these orbital objects for the government, and NASA’s Conjunction Assessment Risk Analysis program evaluates close-approach risks and alerts mission managers of any potentially hazardous situations. Because of the growing number of commercial satellites, including several large constellations, the Department of Commerce is building a system to predict close approaches for all operators, the Traffic Coordination System for Space (TraCSS). Assessing the risk of these close approaches falls to the satellite operator. Due to the highly specialized analysis involved, many rely on private companies to ensure the safe operation of their satellites.

For these companies, receiving thousands of conjunction alerts and determining which are of main concern is an increasingly difficult job.

“A lot of them are low-risk, but for a human to be able to go through all those alerts and be able to positively identify the high-risk events is just not possible,” said Siamak Hesar, CEO of the company Kayhan Space Corp. Based in Broomfield, Colorado, Kayhan grew out of the need for situational awareness in the increasingly crowded low-Earth orbit.

Hesar used to work at SpaceNav, a company founded by a former NASA contractor that assisted NASA in making orbital safety assessments for such missions as the Global Precipitation Measurement mission’s Core Observatory and Orbiting Carbon Observatory-2, as well as several CubeSats launched from the International Space Station (ISS).

“We had to figure out the best way for the CubeSats to be deployed, so we did a lot of analysis to figure out the safest direction was for them to get deployed below the ISS,” Hesar said. “As I was seeing Starlink going up, and OneWeb was planning to launch 1,000 satellites, I quickly realized, we are doing all this work manually. We were not set to scale the capabilities to keep these assets safe in orbit.”

In the absence of telescopes or radars to keep track of objects, Kayhan’s Pathfinder system aggregates data of known orbits, and cross references them. When multiple data sources show a close approach, Pathfinder automatically flags an alert for operators to evaluate mitigating the potential collision.

Today, several former NASA personnel and contractors work at Kayhan Space, and the company’s software supports more than 30 satellite constellation operators. Hesar credits his work with NASA with developing his skills in the relatively new field of space situational awareness, and with showing him the need for increased safety in private spaceflight.

“I graduated from the University of Colorado in Boulder, one of the leading institutions when it comes to astrodynamics. But space situational awareness and collision avoidance was not really in our curriculum,” Hesar said. “Even though it’s a very important topic, all the knowledge in the field is gained by people actually doing it.”