The European Space Agency’s Proba-3 mission has launched a pair of satellites designed to create artificial solar eclipses in orbit, offering scientists an unprecedented opportunity to study the middle corona of the sun. This elusive region of the sun’s atmosphere holds key answers to enduring mysteries, such as the acceleration of the solar wind and why the corona is vastly hotter than the sun’s surface.
Launched on December 5 from India, the two satellites will fly in precise formation, separated by 144 meters with millimeter-level accuracy. One satellite will block the sun’s light, mimicking a total solar eclipse, while the other captures high-resolution images of the sun’s atmosphere. Unlike natural eclipses, which are brief and geographically limited, Proba-3 will create artificial eclipses lasting up to six hours, allowing scientists to observe how the corona evolves over time.
Traditional coronagraphs, which block light to study the sun, often suffer from diffraction that distorts images near the solar surface. By separating the satellites at a significant distance, Proba-3 minimizes diffraction, creating a sharper shadow and enabling detailed observations closer to the sun than previously possible. This approach addresses a critical observational gap, as the middle corona, located at distances of one to three solar radii, has been largely inaccessible except during rare natural eclipses.
Proba-3’s mission will generate over 1,000 eclipses during its two-year span, providing extensive data on the sun’s dynamic behavior. Scientists believe this region holds clues to the mechanisms driving the solar wind and the extreme heat of the corona, making it essential for understanding solar activity.
The mission also showcases the potential of precision formation-flying satellites, a technique that could revolutionize future space missions. By linking telescopes across vast distances, similar setups could create ultra-wide telescopes for deep-space observations. Proba-3 is expected to complement data from other spacecraft, laying the foundation for the next decade of solar science.
This innovative mission represents a leap forward in studying the sun and demonstrates how advanced satellite technology can unlock previously inaccessible areas of discovery. Scientists anticipate groundbreaking insights into the sun’s inner workings and the development of tools for future exploration.
