Artificial Eclipse: New Sun Views from Europe
- A pair of satellites, developed with European technology, have successfully simulated a solar eclipse, offering scientists an unprecedented look at the sun's corona.
- The two satellites maintain a formation 150 meters apart as they orbit Earth.
- The sun's corona, the outermost layer of its atmosphere, is substantially hotter than the sun's surface, reaching temperatures as high as 2 million degrees Celsius.
Satellites Stage Artificial Eclipse, Expose Sun’s Corona Role
A pair of satellites, developed with European technology, have successfully simulated a solar eclipse, offering scientists an unprecedented look at the sun’s corona. The Proba-3 mission, launched from the Satish Dhawan Space Centre in India last year, could revolutionize solar science.
The two satellites maintain a formation 150 meters apart as they orbit Earth. One satellite, named Occulter, plays the role of the moon, blocking the sun’s light. This allows the second satellite, the Coronagraph, to observe the sun’s outer atmosphere, or corona, without being overwhelmed by intense light.
The sun’s corona, the outermost layer of its atmosphere, is substantially hotter than the sun’s surface, reaching temperatures as high as 2 million degrees Celsius. This volatile region is the source of solar storms and coronal mass ejections, which can disrupt telecommunications on Earth and trigger auroras.
Typically, the corona is only visible during a total solar eclipse, limiting observation opportunities. The Proba-3 mission offers a solution by creating artificial eclipses for extended study of the sun’s corona and its impact on space weather.
Andrei Zhukov, of the Royal Observatory of Belgium, which developed the Coronagraph’s main optical sensing instrument ASPIICS, said they can create an eclipse once every 19.6 hours, while natural eclipses are rare.
Proba-3 can sustain its artificial eclipse for up to six hours, a importent increase from the few minutes offered by natural eclipses. The satellites maintain alignment with each other and the sun with millimeter precision, while traveling at 1 kilometer per second.
Dutch startup Lens R&D provides sensors for precise solar tracking. irish firm Onsemi contributed light detectors to fine-tune positioning. Software from Poland’s N7 Mobile supports the probe’s formation control systems.
What’s next
The European Space Agency’s Proba-3 mission aims to provide repeatable, extended observations of the sun’s corona, perhaps leading to a better understanding of solar activity and its effects on Earth.