Engineered artificial solar eclipse in Europe provides fresh perspective on the Sun.

      Two satellites equipped with European technology have successfully created an artificial solar eclipse, allowing scientists to observe the Sun's intense corona like never before. The European Space Agency (ESA) collaborated with over 40 space technology companies to develop these probes, including a trio of startups that provided essential technologies for the mission: solar tracking sensors, light detectors for precise positioning, and software that managed the satellites’ complex flight paths.

      Launched from India’s Satish Dhawan Space Centre last year, the Proba-3 expedition may signal a new chapter in solar science. The image taken on May 23, 2025, by the ASPIICS coronagraph aboard Proba-3 shows the Sun’s inner corona, artificially colored dark green.

      The two satellites orbit the Earth in formation, maintaining a distance of 150 meters from each other. One satellite, called Occulter, functions like the Moon during a solar eclipse on Earth, blocking the Sun's light so that its twin, the Coronagraph, can observe the Sun’s outer atmosphere or “corona” without interference from the bright light.

      The Sun’s corona is the outermost layer of its atmosphere and is unexpectedly much hotter than the surface, occasionally reaching temperatures up to 2 million °C. This volatile area of superheated gases is responsible for solar storms and coronal mass ejections, which can interrupt telecommunications on Earth and create stunning Northern Lights displays.

      The corona is usually visible only during a total solar eclipse, providing scientists with only a fleeting opportunity to study it. However, Proba-3’s success could change that.

      As Andrei Zhukov from the Royal Observatory of Belgium, developer of the Coronagraph’s primary optical sensing instrument ASPIICS, noted, “We can generate our eclipse every 19.6-hour orbit, while natural total solar eclipses occur only about once a year, sometimes twice.”

      While natural total eclipses last only a few minutes, Proba-3 can sustain its artificial eclipse for as long as 6 hours. Both satellites can stay perfectly aligned with one another and the Sun to within millimeter precision, all while orbiting Earth at a speed of 1 kilometer per second.

      This accuracy is a result of the innovations from various European companies. Dutch startup Lens R&D, an ESA business incubator graduate, supplied sensors that continuously track the Sun’s position with extreme precision, enabling the intricate choreography of their formation flying.

      Irish firm Onsemi (formerly SensL) contributed highly sensitive light detectors known as silicon photomultipliers, which detect minute changes in the Sun’s shadow across the satellites to adjust their positioning during the eclipse.

      Additionally, software developed by Poland’s N7 Mobile, which transitioned from consumer applications to spacecraft control systems, aids in the probe’s formation control systems.

      All these technologies are part of a European initiative to make a six-hour orbiting eclipse not only achievable but also reproducible.