PARIS — QinetiQ of Belgium will supply the main computers and avionics for the two-satellite Proba-3 formation-flying mission under a contract with the European Space Agency, QinetiQ announced March 30.

Under the contract, valued at 16 million euros ($19.5 million), QinetiQ’s Belgium branch will deliver the avionics suites to Sener of Spain, the Proba-3 prime contractor, in time for a planned launch in 2018 aboard a European Vega rocket.
Proba-3’s overall mission cost is estimated at about 100 million euros and follows two earlier Proba missions that had little in common except for their use of a highly autonomous platform.

Proba-3 spacecraft orbits
The Proba-3 spacecraft will fly in a highly elliptical orbit of 600 kilometers by 60,530 kilometers, inclined at 60 degrees relative to the equator. Credit: ESA

Proba-3 will test precision formation flying in a highly elliptical orbit of 600 kilometers by 60,530 kilometers, inclined at 60 degrees relative to the equator.

The two satellites — one equipped with a camera, the other with a sun-occulting dish — will be launched as a single unit before separating in orbit. For six hours of each orbit, they will be kept to within 150 meters of each other to permit the study of the sun’s corona using the eclipsing maneuver of the satellite carrying the disk.

The imaging camera is expected to weigh about 283 kilograms at launch, with the occulting satellite weighing about 231 kilograms.

To save on fuel, the two spacecraft will be kept in close formation-flying mode for only six hours of every orbit; for the rest of the orbit they will be allowed to drift apart.

ESA is including onboard a rendezvous experiment to test sensors that could be used in future missions with both cooperative and uncooperative targets, including the capture and de-orbiting of large pieces of space debris, and the in-orbit-rendezvous segment of a Mars sample-return mission.

Formation flying expertise is also viewed as a key capability for future large science missions that would feature multiple launches of components of an observing instrument that would be operated in space.
“Because the two small satellites can operate as a single entity, Proba-3 overcomes existing limitations and opens up exciting new prospects,” Davy Vrancken, business development manager for QinetiQ’s space business in Kruibeke, Belgium, said in a March 30 statement.


Peter B. de Selding was the Paris bureau chief for SpaceNews.