An artist's rendering of the twin STEREO spacecraft observing an erupting sun, released by NASA on February 6.
According to NASA, seeing the whole sun front and back simultaneously will enable significant advances in space weather forecasting for Earth, and improve planning for future robotic or crewed spacecraft missions throughout the solar system.
"These views are the result of observations by NASA's two Solar Terrestrial Relations Observatory (STEREO) spacecraft. The duo are on diametrically opposite sides of the sun, 180 degrees apart. One is ahead of Earth in its orbit, the other trailing behind," NASA said in a statement.