The mystery of solar eclipses has fascinated humanity for generations., but now, thanks to an unprecedented technological advance, scientists have managed to reproduce this phenomenon on demand and thousands of kilometers from the Earth's surface. The European Space Agency (ESA) has been responsible for executing the experiment in orbit. first artificial solar eclipse, thereby achieving a historic milestone in astronomical observation and the study of the Sun.
This achievement comes from the mission Proba-3, composed of two small satellites –Occulter and Coronagraph– that They fly in formation just 150 meters apartUsing European navigation, positioning, and control technologies, both devices manage to remain perfectly aligned with an accuracy of less than a millimeter, essential for simulating the effect of the Moon blocking out the Sun during a total eclipse.
How is an artificial solar eclipse generated?
The key to the mission lies in the function of each satellite: The Occulter acts as an 'Artificial Moon', blocking intense sunlight thanks to a 1,4-meter diameter disc. The shadow created – just 8 centimeters wide – falls exactly on the second satellite, the Coronagraph, which carries the sophisticated ASPIICS instrument. This specialized telescope obtains images of the solar corona, the outermost and most mysterious layer of the Sun's atmosphere, allowing it to be studied in detail without the blinding veil of the solar disk.
Unpublished images and what they reveal about the Sun
The The first images obtained by Proba-3 are revolutionizing the way we view the solar corona.These are achieved by combining three different exposures, each with a specific time, and thus achieving a complete and detailed view that is usually only visible for brief moments during natural eclipses.
The images show spectacular details in various colors Reflecting different elements and temperatures: dark green hues reveal the presence of ultra-hot iron, yellow highlights solar prominences—giant loops of plasma—and violet reveals structures called coronal streamers. Thanks to the mission's design, these observations are achieved without interference from the atmosphere and with unprecedented quality.
The solar corona is one of the most enigmatic regions of the Sun: Although it is farther from the core, it reaches temperatures of up to 2 million degrees Celsius, much higher than the visible surface of the star. Understanding why this happens, and how coronal mass ejections affect space weather and telecommunications on Earth, is one of the key objectives of the Proba-3 mission.
Technological innovation and international cooperation
Behind this project there is a European collaboration involving more than 29 companies from 14 different countriesContributions range from solar tracking sensors to light detectors produced by European startups, as well as fully designed control software to orchestrate the precise orbital choreography required by the mission. The consortium is led by ESA and includes direct participation from the Spanish company Sener, among other technology firms.
In addition to the cameras, Proba-3 is equipped with instruments that measure solar energy and detect energetic particles., thus expanding the scientific scope of the mission. The entire process takes place in an elliptical orbit ranging from 600 to 60.000 kilometers in altitude and is carried out primarily near apogee, when the gravitational influence and friction of Earth's atmosphere are minimal, saving fuel and maintaining alignment for hours.
A new paradigm for solar science
The Proba-3 mission represents a Paradigm shift: allows the scientific community to replicate and study solar eclipses at will, opening the door to experiments and analyses that were previously impossible. Among the biggest beneficiaries are those researching space weather, plasma physics, and the Sun's influence on Earth.
ESA applies a policy of open data: anyone can access the uncalibrated images and measurements, facilitating collaborative work and participation by scientists, astronomy enthusiasts, and amateurs alike. Over the planned two-year mission, more than 1.000 hours of coronal images are obtainedOnce the fuel is exhausted, the Proba-3 satellites will disintegrate upon re-entering the Earth's atmosphere.