NASA has released the first ever 360-degree view of the sun, taken by two probes on opposite sides.
The STEREO probes moved into position yesterday, and are now beaming back uninterrupted images of the entire star, front and back. The probes will beam back images of the entire sun for the next eight years, and should help forecasters predict space weather more accurately.
In the past, an active sunspot could emerge on the far side of the sun completely hidden from Earth - and then, as the sun rotates, be turned towards Earth, spitting flares and clouds of plasma with little warning.
"Not anymore," says Bill Murtagh, a senior forecaster at NOAA's Space Weather Prediction Center in Boulder, Colorad. "Farside active regions can no longer take us by surprise. Thanks to STEREO, we know they're coming."
NOAA is already using 3D STEREO models of coronal mass ejections to improve space weather forecasts for airlines, power companies and satellite operators.
But the improved forecasts won't only benefit these customers.
"With this nice global model, we can now track solar storms heading toward other planets, too," points out Guhathakurta. "This is important for NASA missions to Mercury, Mars, asteroids… you name it."
And, naturally, the images will improve understanding of the sun itself. For example,it's long been suspected that solar activity can 'go global', with eruptions on opposite sides of the sun triggering and feeding off of one another. Now this can be properly studied.
"For the first time ever, we can watch solar activity in its full three-dimensional glory," says team member Angelos Vourlidas. "This is a big moment in solar physics. STEREO has revealed the sun as it really is - a sphere of hot plasma and intricately woven magnetic fields."