ABSTRACT

In late October 2006, the twin STEREO spacecraft were launched into orbits around the Sun. Their primary goal is to improve the understanding and prediction of the behavior of solar storms by viewing the Sun from two widely separated vantage points, enabling the study of these storms in three dimensions rather than the usual two. The instrument complements, identical on both spacecraft, include white light coronagraphs, all-sky imagers, several energetic particle detectors, a magnetic field detector, and a radio astronomy receiver. To date, important and often surprising observations of the solar storms propagating from the sun to the orbit of Earth have been made. However, as is frequently the case, serendipity has played a crucial role in the early observations from STEREO. In addition to the solar observations for which the mission was designed, unique and important measurements have been made of comets, Earth’s radiation belts, and interplanetary dust.