STEREO spies first major activity of solar cycle 24
Sat May 16, 2009 at 10:29 UTC
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.
The last years of Solar Cycle 23 marked the longest and deepest solar minimum in 100 years. Its unusually small number of active regions and sunspots have led some impatient space-weather watchers to wonder if we were entering another "Maunder minimum." That period, in the late 17th and early 18th centuries, saw few, if any, sunspot regions, and coincided with the deepest part of the "Little Ice Age" of global cooling.
| Source: NASA/Goddard Space Flight Center | |
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