Expanding solar clouds (July 24, 2009)
The HI-1 instrument on STEREO (Ahead) observed as barely visible streams and occasional clouds of solar particles head away from the Sun. The video clip suggests a generally quiet level of solar activity, with a steady streaming of solar particles and three faint clouds that are expanding as they cross the field of view (July 11-18, 2009). The sources of those clouds most likely are small solar storms. The HI-1 instruments on each of the two STEREO spacecraft are wide-angle visible-light imagers that can detect the passage of solar coronal mass ejections (CMEs) through the heliosphere. Each HI instrument has a 20¡ field of view and is off-pointed from the Sun direction by 14.0¡. These are one pair of NASA's space weather watchdogs.
SOHO began its Weekly Pick some time after sending a weekly image or video clip to the American Museum of Natural History (Rose Center) in New York City. There, the SOHO Weekly Pick is displayed with some annotations on a large plasma display.
If your institution would also like to receive the same Weekly Pick from us for display (usually in Photoshop or QuickTime format), please send your inquiry to firstname.lastname@example.org.