Published July 14, 2011
Watch a video of the "dark fireworks."
An unstable magnetic filament near the sun's surface, loaded with cool plasma, triggered the fireworks show of dark blobs and streamers, according to NASA.
The flare was run-of-the-mill for the sun in terms of overall energy—solar physicists spotted 70 similarly bright flashes in 2010. Yet unlike its fiery brethren, the recent flare unleashed four exagrams of ionized gas—a mass comparable to the amount of Earth's total coal reserves—in a blast about as big as ten Earths.
The sun's magnetic fields sucked some of the material back into the solar surface, but the rest launched into space as a coronal mass ejection, or CME. The event ranked in the top 5 percent of the biggest CMEs ever documented, scientists say.
"This one was off to the side and barely missed us. If it faced earthward, we could have seen some significant space-weather effects," said Alex Young, a solar astrophysicist at NASA's Goddard Space Flight Center.
"These large blobs of gas scoop up material during their trip away from the sun and create shock waves ... of high-speed energetic particles. They can be extremely dangerous for astronauts and satellites."
Satellite May Reveal More Solar Storms
NASA's orbiting Solar Dynamics Observatory (SDO), which launched about 17 months ago, recorded the new videos. The sun-facing spacecraft uses a battery of cameras to record solar activity in light ranging from visible to extreme ultraviolet wavelengths.
The comprehensive imagery reveals the plasma blobs that rained down on the sun were about 10,000 to 20,000 degrees Kelvin, or roughly two to four times cooler than the sun's surface. The longer SDO looks, the more common such events may come to seem. (See pictures of solar eruptions.
Watch a video of the solar flare.
"In the past, we could only get snapshots of the sun 12 minutes apart in one wavelength, and not the full picture [of solar activity]. Now we can see events like this one minute apart, in multiple wavelengths," Young said.
"We'll continue to see a lot of things we've never seen before with SDO."
For more on solar flares, sunspots, and solar wind, read "The Sun—Living With a Stormy Star," from National Geographic magazine >>
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