Thrill to a sunspot's parting shot

The sunspot region known as AR1429 seethes in a picture of the sun, captured on March 11 in 

hydrogen-alpha light 

A particularly angry region of the sun has been throwing some strong solar storms toward us over the past week, but there's just one more blast to weather. This picture, from astrophotographer Alan Friedman, shows active region 1429 as it rolls toward the edge of the sun's disk.

Friedman specializes in solar photography that keys in on hydrogen-alpha wavelengths, a part of the spectrum that is particularly well-suited to show variations in the sun's seething surface. The sunspots are magnetically disturbed whorls of plasma that are prone to send out flares and eruptions of electrically charged particles.

Friedman's latest solar shot, taken from his backyard in Buffalo, N.Y., is featured today on NASA's Astronomy Picture of the Day website. To see more of his work, check out his Averted Imagination gallery.

Last week, AR1429 blasted out a series of coronal mass ejections, or CMEs, that sparked colorful auroral displays. They also sparked worries about the potential disruption to satellite communications, electrical grids and GPS navigation. Fortunately, the direction and magnetic orientation of the CMEs weren't as threatening as they could have been.

AR1429 got off a parting shot on Tuesday, in the form of a medium-size M7.9-class flare and eruption. By now, the sunspot region has migrated to near the edge of the sun's disk and is starting to fade. The CME is taking "a path not toward Earth," the National Oceanic and Atmospheric Administration's Space Weather Prediction Center reported. As a result, the eruption is expected to produce "minor to moderate" geomagnetic storms — which shouldn't pose a huge threat to power grids or electronics.

When the wave of charged particles sweeps over Earth's magnetic field, the extra geomagnetic activity should give a boost to the aurora. That could happen as early as tonight. So it's a good idea to check in with the usual suspects, including the prediction center's Facebook page as well as SpaceWeather.com, the Ovation Auroral Forecast page and the University of Alaska's Aurora Forecast website.