ESA’s Proba-3 Mission, Ready to Launch at the End of the Year

The Proba-3 mission of the European Space Agency (ESA) is successfully completing its pre-launch tests, as announced today at an event at the Redwire facilities in Kruibeke, near of Antwerp (Belgium). Led by Sener, in close collaboration with an industrial team consisting of Redwire, Airbus, GMV and Spacebel, and encompassing a large consortium of over 29 companies from 17 countries, Proba-3 will demonstrate the viability of high-precision formation flying by satellites in space.

Both Spain and Belgium are involved in Proba-3. Sener is the mission’s lead contractor, responsible for both the flight and ground segments, with Airbus Defence and Space, which carried out the design and manufacture of the two platforms, and GMV, which developed the Formation Flying Subsystem (FFS), the Flight Dynamics System (FDS) and the relative GPS function (rGPS), rounding out Spanish industry’s participation. As for the Belgian industries, Redwire is handling avionics and operations, and completing functional testing of the satellites, as well as the integration and one of the scientific instruments (3DEES), and Spacebel has developed both the on-board software and the ground segment, as well as the simulator for both satellites.

The event was attended by various officials, such as Léa Bossaert, from the Belgian government’s Office of the State Secretariat for Economic Recovery and Strategic Investments, Dietmar Pilz, Director of Technology at ESA, and Juan Carlos Cortés, Director of Programmes at the Spanish Space Agency. At the event, Dietmar Pilz, from ESA, Diego Rodríguez, Business Development General Manager of Space and Science at Sener, Frank Preud’homme, Sales and Business Development Director for Redwire in Belgium, and Andrei Zhukov, Principal Investigator at the Royal Observatory of Belgium, explained the characteristics of the mission.

In his remarks, Dietmar Pilz noted: “Proba-3 will be the first mission to demonstrate the feasibility of exquisite, millimeter-scale high-precision formation flight between satellites in space. The satellites will fly in a coordinated way, acting as a single instrument to mimic a solar eclipse on demand. It is an extremely technical challenging mission which will require unprecedented accuracy. I am pleased to see Proba-3 is entering its final steps of verification. It has been a long journey which has been possible thanks to the commitment and work of the industrial consortium of companies that worked together to make it possible under ESA’s General Support Technology Programme (GSTP). I wish all the luck to an important mission that will enable future projects, following ESA’s mandate to support technical demonstration missions”.

To execute the mission, the two satellites, which will fly in an elliptical orbit to a little over 60,000 km from Earth (more than 10 times the distance from the surface to the Earth’s core), will have to be synchronised. Another challenge facing the mission is the autonomy of the satellites. Each of them will act independently, calculating its position and trajectory with respect to its counterpart, without support from a human operator, using advanced guidance, navigation, and control (GNC) systems, a branch of engineering that deals with the design of systems to control the movements of both manned and unmanned vehicles.

The Coronagraph satellite will house the mission’s coronagraph, an instrument that will point directly at the Sun. The second satellite, Occulter, will eclipse the Sun, placing itself between the Sun and the Coronagraph. It will do so by means of a disc measuring 140 centimetres in diameter and various (optical and laser) devices that will be used to calculate the relative positions and attitudes of the two satellites to position them very accurately.

The perfect synchronisation between the two satellites will create an artificial eclipse in a way that has never been achieved before: the coronagraph in space will be able to obtain images of the Sun that will be unaffected by disturbances in the Earth’s atmosphere, while the Occulter satellite, located hundreds of metres from the focal point of the optical instrument, will greatly reduce the effects of diffraction.

By flying in formation, the satellites can act as a single optical instrument, creating a virtual structure in space that is highly reconfigurable. The Proba-3 mission aims to demonstrate that future missions can be carried out on a larger scale and at a lower cost by using multiple small modules that behave in flight as a single large satellite.

Proba-3 is part of the ESA’s General Support Technology Programme, and Spain’s participation was made possible thanks to the support of the Centre for Technological and Industrial Development, as well as thanks to a close collaboration between companies internationally.

In this regard, José Julián Echevarría, Managing Director of Aerospace and Defence at Sener, notes that: “Proba-3 is a particularly ambitious mission, with great potential to benefit aerospace engineering and astronomy. But it is also a great example of industrial collaboration, and we are proud to be part of it. This milestone is the result of over 25 years of work in guidance, navigation, and control systems”.

The Vice President of Airbus DS Space Systems in Spain, Luis Guerra Peña, expressed: “We are excited to be part of this international collaboration, contributing with the two satellite platforms. The Proba-3 mission represents a significant milestone in space exploration and cooperation between countries. We are especially proud to contribute to the advancement of science and technology.”

According to Enrique Fraga, Managing Director of EST Space Systems at GMV, “Proba-3 will mark a turning point in space missions with distributed elements (formation flying). One of the mission’s keys is the accuracy of the relative positioning between several vehicles that work as one, thanks to the GNC subsystem, and its high degree of autonomy, so for GMV it was a pleasure to provide its experience of over 30 years in the solutions implemented for both the GNC and the Flight Dynamics systems”.

The Sales and Business Development Director for Redwire in Belgium, Frank Preud’homme, has said: “Redwire is very proud to be a part of the innovative Proba-3 mission and to leverage our expertise to advance this important science and technology demonstration. Proba-3 will provide critical data from the Sun that will benefit life on Earth and help further precision formation flying, which will be essential for future European missions”.

The CEO of Spacebel, Thierry du Pré-Werson, stated that “Proba-3 is definitely one of our flagship projects that perfectly demonstrates our cross-functional skills at all levels of the Space industry. For several years, this highly challenging project has represented a significant workload for the Spacebel teams. In a certain way, it represents the acknowledgement of our company among the leaders of the European Space sector. I would like to thank Sener and ESA for their confidence and cooperation”.