WASHINGTON — In a mission targeted for 2025, a robot satellite in geostationary orbit around 22,000 miles above Earth will rendezvous with a military satellite and attempt to affix a new imaging sensor payload on the spacecraft.

The servicing vehicle — equipped with a robot arm developed by the Defense Advanced Research Projects Agency and the Naval Research Laboratory — will seek to connect the payload to the satellite’s launch adapter ring. This ring, which originally connected the satellite to its rocket during launch, will provide the attach point for an electro-optical imaging sensor payload developed by the startup Katalyst Space Technologies.

While conceptually straightforward, executing such delicate hardware upgrades on a multi-ton satellite constitutes a major technological challenge many years in the making, Ghonhee Lee, chief executive of Katalyst Space, told SpaceNews

DIU selected startups

The satellite-upgrade effort is overseen by the Defense Innovation Unit (DIU) which selected the Pasadena, California-based startup Motiv Space Systems in 2022 to prototype satellite-servicing hardware for DIU’s “Modularity for Space Systems” program. DIU in January 2024 expanded the agreement to include Katalyst Space, based in Flagstaff, Arizona, 

The Mission Robotics Vehicle (MRV) that will perform this mission is being built by Northrop Grumman’s subsidiary SpaceLogistics. The company under an agreement with DARPA is equipping the vehicle with two robot arms designed by NRL with DARPA funding.

Motiv Space, known for its space robotics expertise, is providing engineering support. Katalyst Space, which specializes in on-orbit servicing hardware, designed a “space domain awareness” sensor that gives a satellite greater visibility of its surroundings in the GEO belt, a crucial zone for military communications and reconnaissance spacecraft.

Katalyst is also supplying a “retrofit attachment system” to facilitate the attachment of a payload on unprepared satellites. Lee explained the retrofit system allows a payload to be installed on the satellite’s existing launch adapter ring. 

“Most satellites in geosynchronous orbit have these rings, which were originally used to interface with a rocket during launch,” he said. “The 2025 mission will be the first attempt to install a new payload to a satellite by attaching to the launch adapter ring.”

The Naval Research Laboratory will test the payload to ensure it can be installed with the NRL-designed robot arm, said Lee. Katalyst also has to flight-qualify the retrofit attachment system.

Tapping commercial tech

DIU’s Modularity for Space Systems project is an effort to match commercial technologies with military needs for in-orbit services.  “The U.S. government manages an aging satellite fleet that, in some cases, has systems running well beyond their recommended operational life,” DIU said. “Post-launch serviceability has historically not proven reliable or cost-effective.”

The MRV is a commercial vehicle that SpaceLogistics will use to service client satellites. The company in 2020 signed a cooperative agreement with DARPA that allows the MRV to deploy the robotic arms. Once launched, the MRV is designed to stay on orbit for 10 years, scooting around in space from one repair job to the next. 

The military customer for the sensor upgrade mission is the Space Force’s Delta 11 unit that conducts training exercises and wargames. The Pentagon’s Test Resource Management Center co-funded the project with DIU.  

Delta 11 relies on ground-based sensors to monitor GEO orbit and practice orbital maneuvers, but having a sensor satellite actually in space will give Delta 11 a more “operationally representative on-orbit environment” to rehearse and practice orbital warfare, said Maj. William Westcott, director of operations of Delta 11’s 98th Space Range Squadron. 

“Upgrading the spacecraft that we already have is a new capability that gives us flexibility to meet our mission needs on timelines that are relevant,” he said. 

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...