NASA - National Aeronautics and Space Administration

STEREO Spies First Major Activity of Solar Cycle 24

STEREO (Behind) spacecraft observed a coronal mass ejection (CME) that erupted on the sun on May 5. Shocks accelerated by the CME produced a large Type II radio burst. The source of the CME is an active region (seen as a bright area in the green EUV 195 still) just rotating into view from STEREO Behind, and it is being followed by another.Credit: NASA/SOHO
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NASA′s Solar Terrestrial Relations Observatory (STEREO) spacecraft has spotted the first major activity of the new solar cycle. On May 5 STEREO-B observed a Type II radio burst and a bright, fast coronal mass ejection (CME) emanating from the far side of the sun. The activity originated in a solar active region that rotated into view from Earth on May 8.

A Type II radio burst is a discharge of radio waves that are emitted when shocks are accelerated by a CME—the sudden eruption of energy and solar material.

The active region appears well above the sun′s equator, at about 30 degrees latitude, which indicates it is part of the new solar cycle. Activity from the previous solar cycle would appear nearer to the sun′s equator. These regions also have a distinct magnetic organization characteristic of new cycle regions.

″This is a really exciting opportunity to observe the first major outbreak of solar activity in Solar Cycle 24,″ says Joseph Gurman, the newly named project scientist for STEREO at Goddard Space Flight Center. Gurman officially takes the helm from current project scientist Michael Kaiser on June 1.

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About STEREO

STEREO (Solar TErrestrial RElations Observatory) is the third mission in NASA's Solar Terrestrial Probes program (STP). This two-year mission, launched October 2006, will provide a unique and revolutionary view of the Sun-Earth System. The two nearly identical observatories - one ahead of Earth in its orbit, the other trailing behind - will trace the flow of energy and matter from the Sun to Earth. They will reveal the 3D structure of coronal mass ejections; violent eruptions of matter from the sun that can disrupt satellites and power grids, and help us understand why they happen. STEREO will become a key addition to the fleet of space weather detection satellites by providing more accurate alerts for the arrival time of Earth-directed solar ejections with its unique side-viewing perspective.