European Satellites Create Artificial Solar Eclipse to Study Corona

PARIS — In a groundbreaking achievement, a pair of European satellites have successfully created the first artificial solar eclipse, allowing scientists unprecedented access to study the sun's corona. The European Space Agency (ESA) unveiled this remarkable feat during the Paris Air Show on June 17, 2025, showcasing images captured by the Proba-3 mission.

Launched in late 2024, the Proba-3 satellites have been conducting simulated solar eclipses since March 2025, operating tens of thousands of kilometers above Earth. The two satellites, flying 150 meters apart, are designed to mimic the natural alignment of the Earth, moon, and sun. One satellite acts as a shield, blocking the sun’s light like the moon during a total solar eclipse, while the other satellite aims its telescope at the corona, the sun's outer atmosphere that radiates a halo of light. This intricate maneuvering requires extreme precision, with the satellites needing to maintain a positional accuracy within a mere millimeter, akin to the thickness of a fingernail.

This autonomous operation relies on advanced technologies such as GPS navigation, star trackers, lasers, and radio links. According to ESA's mission manager Damien Galano, the Proba-3 mission has successfully generated ten solar eclipses so far during its initial checkout phase, with the longest eclipse lasting five hours.

Dr. Andrei Zhukov, lead scientist at the Royal Observatory of Belgium, stated, "We almost couldn’t believe our eyes. This was the first try, and it worked. It was so incredible." Zhukov anticipates achieving a six-hour totality for future eclipses as the mission transitions to its scientific observation phase in July 2025. Over the course of the two-year mission, scientists expect to produce an average of two solar eclipses per week, amounting to nearly 200 eclipses and over 1,000 hours of totality.

The ability to replicate the conditions of a total solar eclipse holds significant scientific promise. Natural solar eclipses occur infrequently, averaging once every 18 months, and provide only a few minutes of totality. The sun's corona remains an area of intense study due to its mysterious properties; it is hotter than the solar surface, and coronal mass ejections can result in disruptive geomagnetic storms on Earth.

Prior missions, including ESA's Solar Orbiter and NASA's Soho observatory, have also attempted to simulate solar eclipses. However, Proba-3 distinguishes itself by using two separate satellites, allowing for a more comprehensive observation of the corona, especially the region closest to the sun's edge. Zhukov emphasized the importance of this separation, stating, "The distance between these two satellites will give scientists a better look at the part of the corona closest to the limb of the sun."

The implications of the Proba-3 mission extend beyond mere scientific curiosity. Understanding the dynamics of the sun's corona could contribute to improved forecasting of space weather phenomena, which can have profound effects on satellite operations, communications, and power grids on Earth. As the Proba-3 mission continues, it promises to yield valuable insights into solar activity, enhancing our comprehension of the sun's influence on our planet and beyond.