<
https://www.theguardian.com/science/2024/nov/30/landmark-space-mission-set-to-create-artificial-solar-eclipses-using-satellites>
"Final preparations have begun for a landmark space mission that will use
satellites flying in close formation to create artificial solar eclipses high
above the Earth.
The Proba-3 mission is the European Space Agency’s first attempt at precise
formation flying in orbit and calls for two spacecraft to loop around the
planet in an arrangement that never deviates by more than a millimetre, about
the thickness of a human fingernail.
All being well, the spacecraft will blast off from India’s Satish Dhawan Space
Centre in Sriharikota, on the Bay of Bengal coast, at 4.08pm local time
(10.38am UK time) on Wednesday. After a four-month voyage, the probes will
reach a highly elliptic orbit that swoops as close as 370 miles to Earth before
swinging out for more than 37,000 miles.
“It’s an experiment in space to demonstrate a new concept, a new technology,”
said Damien Galano, the Proba project manager at ESA. “It’s very challenging
because we need to control very well the flight path of the two spacecraft.”
If the satellites operate as intended, they will line up with the sun such that
the lead spacecraft casts a carefully controlled shadow on its partner,
allowing instruments on the latter to measure the sun’s corona, the outer layer
of its atmosphere.
Traditionally, scientists have studied the sun’s ring-like corona during solar
eclipses, when the moon blocks enough of the sun’s glare to make the corona
visible from Earth. The work requires scientists to chase eclipses around the
world, often for only minutes of observation time, or none at all if the view
is obscured by cloud.
The €200m (£166m) Proba-3 mission promises to transform scientists’
understanding of the corona by producing 50 artificial solar eclipses a year,
each lasting six hours. The lead spacecraft carries a 1.4-metre wide occulter
disc to block the sun as seen from the second spacecraft, turning the pair into
a 150-metre-long instrument called a coronagraph.
Data from the mission should shed light on the longstanding mystery of why the
corona is so much hotter than the sun itself; the sun’s surface is about
5,500C, but the corona can exceed 1 million C.
By better understanding the corona, scientists hope to improve their
predictions of solar weather, coronal mass ejections – where pulses of plasma
and magnetic field burst into space – and solar storms, which can damage
spacecraft and cause power outages and communications blackouts on Earth."
Cheers,
*** Xanni ***
--
mailto:xanni@xanadu.net Andrew Pam
http://xanadu.com.au/ Chief Scientist, Xanadu
https://glasswings.com.au/ Partner, Glass Wings
https://sericyb.com.au/ Manager, Serious Cybernetics
