Scientists can take a longer, clearer look at the Sun’s outer atmosphere thanks to a European mission that created the first artificial solar eclipse in space.
The feat was made possible by the European Space Agency’s Proba-3 mission, which involved two spacecraft flying in perfect formation more than 600km above Earth.
The pair lined up to block out the bright disc of the Sun and reveal its faint outer atmosphere, called the corona, creating an artificial eclipse. Striking composite images were released on Monday by the space agency.
Dr Dimitra Atri, principal investigator at the New York University Abu Dhabi’s Space Exploration Laboratory, said the achievement amounted to a breakthrough in solar science.
“It will help us tackle one of the field's biggest puzzles: why the Sun's corona burns hundreds of times hotter than its surface,” Dr Atri, was not involved in the research, told The National.
He said researchers would now be able to study the corona for hours at a time by creating the much longer artificial solar eclipses.
“This gives us an opportunity to study the turbulent processes that fuel space weather,” he said.
The surface of the Sun reaches about 5,500°C, while the corona can reach more than a million degrees.
Current theories suggest the extreme heat could be caused by the Sun’s magnetic fields and waves of charged particles, but this could be challenged with Proba-3's feat.
To make the eclipse appear, the two satellites flew in a carefully controlled formation, maintaining a fixed distance of 144 metres while orbiting Earth.
One satellite blocked the Sun’s light while the other captured images of the exposed corona. This required millimetre-level precision to align perfectly, said the European Space Agency.
Studying the Sun’s secrets
During a natural eclipse, scientists have only a few minutes to view and photograph the corona.
This region is where violent solar activity originates, including flares and coronal mass ejections that can damage satellites, disrupt navigation systems and cause power cuts on Earth.
“The mission will dramatically improve our ability to forecast solar storms that threaten satellites and electrical grids, while deepening our knowledge of how stars function across the universe,” said Dr Atri.
“The engineering feat of keeping two spacecraft flying in precise formation also opens new doors for future more complex missions.”
Six-hour eclipse
Andrei Zhukov, from the Royal Observatory of Belgium, who was part of the research, said he was thrilled to see the images as they secured them in the first attempt.
“Our artificial eclipse images are comparable with those taken during a natural eclipse,” he said in a statement.
“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.
“On top of that, natural total eclipses only last a few minutes, while Proba-3 can hold its artificial eclipse for up to six hours.”
