Streaming Solar Wind and More

The Heliospheric Imager (HI) on the STEREO Ahead spacecraft observed as solar wind streamed from the Sun and three coronal mass ejections (CMEs), which appear as more distinct, elongated clouds, expanded into space over a 15-day period (Mar. 11- 25, 2010). The HI instruments on each of the two STEREO spacecraft are off-pointed from the Sun to observe a 20 degree field of view to the left and the right of the Sun, beginning four degrees from the Sun's center. Its sensitive instruments are attuned to observing the faint structures and particle streams billowing out from the Sun. With the two perspectives scientists are gaining a better understanding of how solar wind and CME structures evolve as they head into space. Solar wind constantly streams away from the Sun, while CMEs are less frequent but much more powerful clouds of particles caused by solar explosions.

• Puffs_HI_best.mov   
• Puffs_HI_med.mov   
• Puffs_HI_sm.mov   
• Puffs_HI.mpg   
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