GSSAP satellites collect space situational awareness data allowing for more accurate tracking and characterization of man-made orbiting objects. Credit: Northrop Grumman

For some time now, alarms have been sounding in the United States military over activities of Chinese and Russian spacecraft in orbit that are viewed as potentially threatening.

U.S. military leaders have called out Russia for deploying so-called inspector vehicles in close proximity to American spy satellites, raising suspicions about their intentions. And they expressed concern when a Chinese spacecraft equipped with a robotic arm towed a defunct geostationary satellite to a graveyard orbit, raising the specter of a future system that could be used to seize U.S. assets.

To keep an eye on these potentially hazardous activities, military officials have called for improved capabilities to conduct intelligence, surveillance, and reconnaissance in orbit, also known as space domain awareness.

Ensuring the U.S. is fully aware of what rivals are doing in space “is a genuine concern,” said Lt. Gen. Philip Garrant, deputy chief of space operations for strategy, plans, programs and requirements.

“Physics absolutely makes it hard,” Garrant said. “It’s not just tracking and monitoring but also characterizing what type of spacecraft it is, and anticipating its behavior.”

To tackle this challenge, the Space Force is ramping up spending on sensors and data analytics, Garrant said. The 2024 budget proposal includes $584 million for space domain awareness programs, or $100 million more than what was allocated in 2023. He noted that most of the added spending is focused on geosynchronous orbit, where the military parks its most valuable satellites.

Lt. Gen. John Shaw, deputy commander of U.S. Space Command, told reporters at the Space Symposium last month that the military looks forward to the deployment of SilentBarker, a space surveillance satellite co-developed by the Air Force and the National Reconnaissance Office to improve situational space awareness in geostationary Earth orbit.

SilentBarker, scheduled to launch to orbit later this year, will supplement the coverage provided by six Geosynchronous Space Situational Awareness Program (GSSAP) satellites that have been in orbit for several years. The two newest GSSAP satellites launched to orbit in January 2022.

NRO Director Chris Scolese told reporters at the Space Symposium that there will be “more than one” SilentBarker. “We expect it will be a useful capability, and we’ll be looking for additional satellites,” he said.


Besides government-built satellites, there are now commercially available technologies for in-orbit space domain awareness. Shaw said the military doesn’t necessarily care where the capabilities come from as long as they work. “I do think our solution set to this problem is probably a blend of a lot of things,” he said.

Shaw noted that one of the problems with GSSAP and other big-ticket DoD spacecraft is their limited ability to maneuver so they can get a better view of an object. These satellites were built to stay in orbit for decades and live off their existing fuel supply, so their movement has to be minimized.

In response to the military’s demand for maneuverable surveillance systems, the commercial space industry is working on new products.

Redwire, for example, plans to demonstrate later this year a small camera that could be put on satellites to observe and characterize suspicious objects. Pending the outcome of the demonstration, Redwire says it could mass produce the camera and offer it to the military.

The startup True Anomaly plans to launch an experiment with two small satellites this fall where one will attempt to chase down an uncooperative object and take pictures up close. The company plans to market these vehicles to the military to boost domain awareness.

Another startup, Katalyst Space, is working on a space surveillance sensor designed to be mounted on satellites to help track debris and other threats in orbit. The company wants to partner with a large defense contractor to test the payload.

These are technologies the industry believes will help the U.S. hold China and Russia accountable for aggressive actions in space and possibly deter such behavior.

If more of these assets are put in orbit, the data collected by government and commercial sensors could be crucial for American military planners to monitor potential threats and develop appropriate response measures.

This article originally appeared in the May 2023 issue of SpaceNews magazine.

Sandra Erwin writes about military space programs, policy, technology and the industry that supports this sector. She has covered the military, the Pentagon, Congress and the defense industry for nearly two decades as editor of NDIA’s National Defense...