First Proba-3 science: surprisingly speedy solar wind

Written by Copernical Team Monday, 13 April 2026 08:00

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Imaged of processed Proba-3 data that highlights movement around the Sun

Since July 2025, the European Space Agency’s pair of Proba-3 satellites has already created 57 artificial solar eclipses. So far, the mission has collected more than 250 hours of high-resolution videos of the Sun’s atmosphere, called the corona. That’s the same amount of observing time as about 5000 total solar eclipse campaigns carried out on Earth.

But the science is even more exciting. For the first time we can carefully track how material from the Sun moves through the inner corona, where space weather is born. The first results, recently published in The Astrophysical Journal Letters, show that solar wind structures in the inner corona can travel three to four times faster than scientists thought.

About Proba-3

Proba-3 is the European Space Agency's first eclipse-making mission. The mission consists of two satellites – the Coronagraph and the Occulter. Since their launch in December 2024, the satellite duo has claimed not one, but two world firsts – the first precise formation flight, setting the mission up for its first artificial solar eclipse in orbit.

After having achieved all of its technology goals, the mission has completed more than 60 extremely accurate formation flying orbits so far. Of these, 57 were dedicated to creating artificial eclipses, allowing the Coronagraph to observe the highly dynamic inner region of the Sun's corona. By providing scientists with hours of science data per artificial eclipse, Proba-3 has accomplished a major feat in space-based solar and heliophysics research.

Aside from the ASPIICS coronagraph, Proba-3 carries two more instruments that can be used for science.

Proba-3’s Digital Absolute Radiometer (DARA) instrument has been continuously measuring the Sun’s energy output with unprecedented accuracy and precision. Its main goal is to investigate how much the Sun’s energy output changes over time.

With its 3D Energetic Electron Spectrometer (3DEES) instrument, Proba-3 is measuring the number, direction of origin and energies of electrons in Earth's Van Allen radiation belts. This data can be used to reveal the behaviour of Earth's radiation belts under normal conditions, and how they are affected by solar wind and coronal mass ejections.