Proba-3's first artificial solar eclipse

Summary

Enabling & Support Proba-3’s first artificial solar eclipse 16/06/2025 24672 views 108 likes Today, the European Space Agency’s Proba-3 mission unveils its first images of the Sun’s outer atmosphere – the solar corona. The mission’s two satellites, able to fly as a single spacecraft thanks to a suite of onboard positioning technologies, have succeeded in creating their first ‘artificial total solar eclipse’ in orbit. The resulting coronal images demonstrate the potential of formation flying technologies, while delivering invaluable scientific data that will improve our understanding of the Sun and its enigmatic atmosphere. Proba-3 infographic: Formation flying to a fingernail's thickness Two spacecraft flying as oneThis March, Proba-3 achieved what no other mission has before – its two spacecraft, the Coronagraph and the Occulter, flew 150 metres apart in perfect formation for several hours without any control from the ground.While aligned, the pair maintain their relative position down to a single millimetre – an extraordinary feat enabled by a set of innovative navigation and positioning technologies.Demonstrating the degree of precision achieved, the two spacecraft use their formation flying time to create artificial total solar eclipses in orbit – they align with the Sun so that the 1.4 m large disc carried by the Occulter spacecraft covers the bright disc of the Sun for the Coronagraph spacecraft, casting a shadow of 8 cm across onto its optical instrument, ASPIICS. Proba-3 Occulter eclipsing Sun for Coronagraph spacecraft This instrument, short for Association of Spacecraft for Polarimetric and Imaging Investigation of the Corona of the Sun, was developed for ESA by an industrial consortium led by Centre Spatial de Liège, Belgium. When its 5 cm aperture is covered by the shadow, the instrument captures images of the solar corona uninterrupted by the Sun’s bright light.Observing the corona is crucial for revealing solar wind, the continuous flow of matter from ...