Satellites Create Artificial Solar Eclipse
- Editor OGN Daily
- Jun 19
- 2 min read
Two satellites’ highly precise alignment allows scientists to study the sun’s outer atmosphere like never before.
One of the ways that scientists study solar wind - charged particles streaming from the sun’s surface - is by observing the sun’s outer atmosphere, called the corona. But because the sun is so blindingly bright, observations of this ethereal region can only really be conducted during a total solar eclipse, and they don't happen very often. And, when they do, they only last a few minutes.
To address this problem, a consortium led by the European Space Agency (ESA) decided to create its own solar eclipses. So, late last year, the agency fired the Proba-3 mission into space, taking with it two spacecraft: the Coronagraph and the Occulter. Now, the Earth-orbiting satellites have flown in “perfect formation,” 492 feet apart from each other, for hours, with one blotting out the surface of the sun from the other’s perspective in a first-of-its-kind feat.
Carefully monitored by ground control, the satellites aligned and maintained their relative positions, down to a single millimeter, autonomously. “We almost couldn’t believe our eyes,” Andrei Zhukov, the principal investigator for the Coronagraph’s optical instrument at the Royal Observatory of Belgium, told the Associated Press. “This was the first try, and it worked. It was so incredible.”
“Our ‘artificial eclipse’ images are comparable with those taken during a natural eclipse. The difference is that we can create our eclipse once every 19.6-hour orbit, while total solar eclipses only occur naturally around once, very rarely twice, a year,” Zhukov explains in an ESA statement. “On top of that ... Proba-3 can hold its artificial eclipse for up to six hours.”
The mission should provide insight into a kind of solar activity called coronal mass ejections (CMEs): explosions of plasma and magnetic fields from the sun’s surface. CMEs drive the spectacular aurora borealis but can also endanger communication, power and navigation networks.
