WASHINGTON – SpaceX has agreed to run any of its Starlink satellites orbiting near the International Space Station or other NASA spacecraft as part of an agreement between the agency and the company.
NASA announced on March 18 that it had signed an agreement with SpaceX with SpaceX regarding the coordination of the operations of the ISS and other NASA spacecraft with SpaceX’s growing fleet of Starlink satellites in a low-Earth orbit. The agreement, NASA said in a statement, was intended to “formalize both parties’ strong interest in sharing information to maintain and improve space security.”
“With commercial enterprises launching more and more satellites, it is critical that we increase communication, exchange data and establish best practices to ensure that we all maintain a safe spatial environment,” said Steve Jurczyk, acting administrator of NASA, said in the statement.
Under the agreement, SpaceX will use the autonomous collision avoidance feature of its Starlink satellites to move in the event of any close proximity to the NASA spacecraft. The agreement states that it is intended to avoid a case where both parties have maneuvered.
“NASA has agreed not to maneuver in the event of a possible collaboration to ensure that the parties do not accidentally move into each other,” the agreement reads. “NASA will operate on the basis that the autonomous maneuverability of the Starlink satellites will seek to avoid collusion with NASA assets, and that NASA will maintain its planned orbit unless SpaceX notifies otherwise.”
The agreement sets out the roles and responsibilities of NASA and SpaceX regarding the sharing of information about orbital positions and maneuver plans. This requires SpaceX to notify NASA at least one week before each Starlink launch, so that NASA can determine if the mission has any problems in avoiding collisions. SpaceX has also agreed to send Starlink satellites into the first orbits that do not come within five kilometers of the ISS or other NASA spacecraft. SpaceX will also avoid ‘any notifiable connections’ with the ISS in general, which NASA defines as a volume of space 50 by 50 by 4 kilometers, centrally located at the station.
The announcement did not explain the origin of the agreement, which was apparently drafted a few months ago. The text of the deal notes that SpaceX’s Starlink system ‘has more than 600 assets currently in orbit’, a figure it exceeded months ago when it launched new satellites at a frenetic pace. SpaceX currently has 1,260 Starlink satellites in orbit, according to statistics maintained by space expert Jonathan McDowell.
NASA spokeswoman JD Harrington told SpaceNews there was no specific incident, such as a close approach by a Starlink satellite to a NASA spacecraft, that led to the deal. “The technical teams of NASA and SpaceX have worked together for some time to ensure consistent and timely communication,” Harrington said. “This agreement is the result of our cooperation in communication between people and freight.”
SpaceX did not respond to a request for comment on the NASA agreement.
The company has long stressed that the use of automation on Starlink satellites is being decided to perform collision avoidance maneuvers. However, the company is not alone, as other companies planning mega-constellations follow similar approaches.
“Every operator I’ve talked to has a tremendous amount of automation in their systems,” said Ted Muelhaupt, chief executive of Aerospace Corporation’s Center for Orbital and Reentry Debris Studies, during a presentation at a March 9 workshop on the management of space traffic by the LRA Institute. “These vehicles are effective on ‘auto-drive’ and the drivers themselves may not know when a vehicle chooses to maneuver. ‘
While this may increase efficiency, he warned that it will become much more difficult to predict close approximations a few days in the future, as spacecraft can move in an unpredictable way. “When these vehicles do autonomous maneuvers, small maneuvers, they invalidate the assumptions that they were avoided in the first place,” he said. “If you place two large constellations close together, all of these are magnified.”
In addition to working together to avoid the near approaches of spacecraft, the agreement between NASA and SpaceX also covers efforts to reduce the brightness of Starlink satellites, which could impede astronomical observations. NASA said it would “learn technical expertise and lessons to work with SpaceX on developing approaches to monitoring and mitigating the photometric brightness” of satellites, while SpaceX said it would share similar insights with NASA “to to guide the development of the agency’s. ‘