Northrop Grumman’s Mission Extension Vehicle has departed a communications satellite operated by Australian company Optus, after spending more than a year connected to it to help keep it in the correct orbital position. The move makes room for a new generation of vehicles designed to extend satellite lifespans, as the company prepares for its first attempt to install a new propulsion unit on an existing satellite in orbit.
Northrop Grumman launched four vehicles into orbit in July aboard a SpaceX Falcon 9 rocket. The group includes the Mission Robotic Vehicle, known by the abbreviation MRV, a vehicle equipped with two advanced robotic arms developed by the U.S. Defense Advanced Research Projects Agency, DARPA. The other three vehicles are Mission Extension Pods, or MEPs, which are smaller and simpler satellites that function primarily as modular propulsion units.
Installing a New Propulsion Unit in 2027
The four vehicles are currently heading toward targets located approximately 27,000 miles above Earth. In 2027, the MRV will use its two robotic arms to install one of the MEP units on the Optus satellite, which is expected to help it remain in orbit for additional years.
Communications satellites and satellites that use sensors to survey the planet typically stop operating after running out of the fuel needed to maintain their position, rather than because their computers or transceivers fail. The Optus satellite was launched in 2009 and designed to operate for 15 years. If the mission proceeds as planned, the satellite could continue operating and generating revenue for an additional six years.
A Different Model for Satellite Services
The MEV vehicles currently in orbit have a record in this field; two were launched in 2019 and 2020, helping extend the lives of three customer vehicles for a combined total of 10 years, including two Intelsat vehicles and an Optus satellite. MEV-1 will wait in a designated orbit until another customer is found, while MEV-2 will remain connected to an Intelsat satellite until 2030.
MRV differs from MEV in its business model. Satellite operators purchase and own the MEP units, which are then permanently attached to their spacecraft. This allows the MRV to move between multiple vehicles to service them, which could provide a lower-cost offering.
Technical Challenges and Potential Defense Interest
This type of service requires two vehicles to autonomously approach and safely dock with each other while moving at speeds of up to thousands of miles per hour. MEV uses a docking probe that connects to the satellite’s propulsion nozzles, while MRV must carefully secure the MEP units using its robotic arms. MRV was also designed to be refueled in orbit, an experimental step toward capabilities that other vehicles may need in the future.
Northrop Grumman considers its vehicles intended for servicing missions, but this type of capability could attract defense customers, particularly because defense agencies operate high-orbit, high-cost satellites and because DARPA participated in developing the MRV arms. The U.S. Space Force has previously described a Chinese vehicle equipped with robotic arms as a weapon, given its potential use to seize and disable a rival satellite.
Cassie Wong, Northrop’s director of logistics and satellite services, believes these vehicles could later be used to add components to satellites or modify their orbits, and perhaps to service assets in low Earth orbit. By contrast, projects such as Starlink and Amazon LEO are moving toward launching large numbers of inexpensive, replaceable satellites, while large and costly satellites remain candidates for life extension and in-orbit repair.