Proba-3 Mission Revolutionizes Solar Study with Over 50 Artificial Eclipses in Space

The European Space Agency’s Proba-3 mission has made significant strides in advancing solar observation since its launch in December 2024. Within less than a year of operations, the mission has successfully generated over 50 artificial solar eclipses in orbit, reaffirming its capability to provide crucial insights into the Sun’s corona, a region that has long puzzled scientists.

Proba-3, consisting of two satellite components, not only achieved the milestone of executing precise formation flights but also set a precedent with its creation of the first artificial solar eclipse in space. The data collected during these multiple observations have confirmed the mission’s potential to bridge existing gaps in our understanding of the corona’s inner regions.

Historically, space-based instruments have focused on imaging the solar disc and the outer corona, while observations of the inner corona have been sporadic, typically only available during rare total solar eclipses visible from Earth. Proba-3’s configuration allows it to generate solar eclipses on demand, greatly enhancing the volume and quality of data collected. Damien Galano, the mission manager, noted that the advanced positioning technologies used by the spacecraft facilitate reliable observations of this largely unexplored area, where the solar wind accelerates and the majority of coronal mass ejections originate.

Recent observations have enabled scientists to capture intricate details of coronal mass ejections (CMEs), providing unprecedented continuity in monitoring their formation and evolution. Andrei Zhukov, Principal Investigator for the ASPIICS coronagraph aboard Proba-3, emphasized the importance of this capability, highlighting how the mission allows for an uninterrupted view of CMEs as they extend from the solar disc into the inner corona and beyond.

In contrast to natural solar eclipses that occur infrequently and for only a few minutes, Proba-3’s artificial eclipses can be generated once every 19 hours and maintained for up to six hours, significantly increasing observation time. Joe Zender, the project scientist, pointed out that the mission’s total observation time has reached approximately 250 hours over 50 orbits, equating to the data gathered from over 6,000 total eclipse campaigns conducted on Earth.

Launched on December 5, 2024, the two spacecraft comprising Proba-3 were successfully separated six weeks later. They completed their first autonomous formation flight in March 2025, achieving a remarkable level of precision that allows them to hold their relative positions without ground control. This innovative formation flying especially important for creating the artificial solar eclipses that Proba-3 aims to leverage for advancing solar science.