Scientists are set to create an artificial solar eclipse by launching synchronised satellites into space.
The Proba-3 mission is the world’s first precision formation flying mission, requiring twin spacecraft to manoeuvre with a 1 millimetre level of accuracy as they orbit Earth.
The mission, led by the European Space Agency (ESA), is expected to launch from the Satish Dhawan Space Centre in India on Wednesday, with the attempt to create an eclipse taking place in March 2025.
If successful, astronomers will be able to observe the Sun’s corona – the outermost layer of the Sun’s atmosphere – in a way that has never before been possible.
This will allow them to study solar wind and solar storms, as well as better understand the evolution of Coronal Mass Ejections (CMEs) from the surface of the Sun.
Insights into space weather could provide advanced warnings for CME-induced power outages and communications blackouts on Earth, as well as help protect satellites from solar radiation damage.
“When I first heard about it, Proba-3 seemed like science fiction technology. But the real-life design will truly deliver excellent science,” said Andrei Zhukov, principal investigator of Proba-3’s main instrument, Association of Spacecraft for Polarimetric and Imaging Investigation of the Corona of the Sun, (ASPIICS).
“But the real-life design will truly deliver excellent science.”
The two Proba-3 satellites will orbit 144 metres apart, with one of the craft equipped with cold gas thrusters to line up to the exact formation.
The satellite closer to the Sun will feature a 140 centimetre disc that will block out the Sun for the second satellite during 6-hour windows. Together they will be capable of producing 50 artificial solar eclipses a year.
The Proba-3 mission will also play an important role in climate studies by performing ongoing monitoring of the Sun’s energy output.
“Researchers used to talk about the ‘solar constant’ but in fact it is always changing sligtly,. And it’s essential to keep track of the total solar irradiance, because it is the dominant energy input to the surface of the Earth,” said Wolfgang Finsterle, a principal investigator at the Physical Meteorological Observatory Davos (PMOD) in Switzerland.
“It amounts to something like 99.978 per cent of the energy available on Earth, including the conserved solar energy stored in coal and oil. It drives all the dynamic processes of Earth’s climate, so even the tiniest variations are hugely significant.”
