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STEREO (Solar TErrestrial RElations Observatory), launched in 2006, employed two nearly identical space-based observatories - one ahead of Earth, the other trailing behind – that provided the first-ever stereoscopic measurements to study the Sun and the nature of its coronal mass ejections, or CMEs. STEREO currently consists of a single spacecraft, STEREO-A, orbiting the Sun just inside of 1 AU, slowly catching up with Earth. This viewpoint away from the Earth-Sun line allows scientists to see the structure and evolution of solar storms as they blast from the Sun and move out through space.


Photo of Paulett Liewer
Paulett Liewer
Astrophysics & Space Sciences
Photo of Mark Wiedenbeck
Mark Wiedenbeck
Interstellar and Heliospheric Physics