spacetoday.net: NASA spacecraft return nearly complete images of the Sun

Posted: Tue, Feb 8, 2011, 7:05 AM ET (1205 GMT)
STEREO image of full sun (NASA)

Twin NASA spacecraft have now moved into orbital positions that allow them to observe nearly the entire Sun simultaneously. The STEREO spacecraft, launched in 2006 into orbits that slowly drift ahead of and behind the Earth, have now moved into positions 180 degrees apart from each other, one 90 degrees ahead of the Earth and the other 90 degrees behind. From those vantage points they can observe the entire Sun simultaneously for the first time; NASA released the first images from those positions on Sunday. Scientists said the satellites will improve their understanding of the Sun as well as provide early warning of solar storms and other activity that form on the side of the Sun not visible from the Earth.