Yesterday, NASA’s twin STEREO probes moved into position on opposite sides of the Sun. They are now constantly sending back images of the entire star.
Each probe is taking a picture of half of the star, and the images are sent to Earth, where they are combined by researchers to create a sphere. The spacecrafts will study every aspect of the solar activity, in four different wavelengths (all of them in the extreme ultraviolet): solar flares, magnetic filaments, tsunamis…
![An artist's concept of STEREO surrounding the Sun.](http://atramateria.com/wp-content/uploads/2011/02/515170main_STEREOab-sun-orig_full.jpg)
![Latest image of the far side of the Sun based on high resolution STEREO data, taken on February 2, 2011 at 23:56 UT when there was still a small gap between the STEREO Ahead and Behind data. This gap started to close on February 6, 2011, when the spacecraft achieved 180 degree separation, and will completely close over the next several days.](http://atramateria.com/wp-content/uploads/2011/02/515180main_sun360_304_020211_2356ut_full.jpg)
This will incredibly help weather forecasts: farside active regions being monitored, when the Sun’s rotation turns these regions toward the Earth, they can no longer take us by surprise. This is of great importance also for several missions to Mercury or Mars for example, as our satellites can potentially be damaged by solar flares or coronal mass ejections (CMEs). There are already models of CMEs; these will be improved by the full view of our star.
Researchers have long suspected global solar activity, they will now be able to study the phenomenon. Of course, this is only the beginning, movies with higher resolution will be released during the next few weeks, as more data are processed. As the Sun affects many aspects of life on Earth, studying our star to better understand it is definitely of major importance.