A Solar Tsunami

Solar flare on August 1, 2010
A false-color composite shows the
solar flare (bright area at lower left) and large magnetic disturbance
that rippled across the Sun's disk on August 1, 2010. Recorded by
NASA's Solar Dynamics Observatory at extreme-ultraviolet wavelengths,
the hues correspond to coronal gases at temperatures of 1 to 2 million
kelvins. Click here for a larger view.

After oversleeping for more than a year, our star is finally stirring from hibernation. Experts don't expect solar activity to peak until until mid-2013 (and a weak one at that), but the signs of awakening are clearly evident.

A few days ago the Sun let loose with a massive belch. On August 1st at 8:55 Universal Time, orbiting satellites witnessed a sizable flare erupting from the large sunspot region designated 1092. The strength of this outburst was pegged at C3, modest as flares go, but it still triggered an impressive coronal mass ejection, or CME, that shot out from the solar disk at more than 600 miles (1,000 km) per second. Watch the amazing video from NASA's STEREO spacecraft here.

When the flare erupted, NASA's recently-launched Solar Dynamics Observatory also looked on as the magnetic disturbance caused an enormous filament of superheated gas to pulse across the Sun's disk.

All this tumult occurred on the Earth-facing side of the Sun, and skywatchers at far northern and southern locations briefly enjoyed colorful auroral displays on the night of August 3-4.

The Sun has since quieted down, but the big spot in region 1092 has been joined by a second, smaller group (1093) that rotated into view yesterday. Go have a look — but, as always, never try to look at the Sun by eye or using optical aid without using a safe solar filter.

Meanwhile, when the Sun's activity finally does peak, solar physicists will have more spacecraft at their disposal than ever before — despite the news that NASA managers pulled the plug on the Transition Region and Coronal Explorer (TRACE) on June 21st after 12 years of operation.

The workhorse Solar and Heliospheric Observatory (SOHO), a collaboration between NASA and the Rueopean Space Agency, just keeps on chugging (it's nearly 15 years old). Even with the loss of TRACE, NASA still has SDO, STEREO, and ACE (Advanced Composition Explorer) in its arsenal of orbiting sentinels. (By the way, teh STEREO team has a great iPhone app showing the Sun in 3D.)

In addition, the Japan Aerospace Exploration Agency continues to receive great high-resolution images from its Hinode spacecraft.