Sun Unleashes Another Solar Storm Aimed at Earth
On August 21, 2013 at 1:24 am EDT, the Sun erupted with another Earth-directed coronal mass ejection, or CME, a solar phenomenon that can send billions of tons of particles into space and reach Earth one to three days later.
Credit: NASA/ESA SOHO

The sun fired off an intense solar storm at Earth Wednesday (Aug. 21) — the second in two days — hurtling billions of tons of charged particles at our planet, but should not pose a threat to people on the ground, NASA says.

The solar eruption, called a coronal mass ejection, occurred yesterday at 1:24 a.m. EDT (0524 GMT) and sent charged particles streaking outward at 380 miles per second. That's just over 1.3 million mph (2.2 million km/h). The solar fallout from the sun storm is expected to reach Earth within the next three days.

"These particles cannot travel through the atmosphere to harm humans on Earth, but they can affect electronic systems in satellites and on the ground," NASA officials explained in a statement. [Solar Max Photos: Sun Storms of 2013]

Wednesday's solar storm erupted just 21 hours after another powerful coronal mass ejection (NASA calls them CMEs) on Tuesday (Aug. 20). That solar tempest also sent billions of tons of solar particles on their way to Earth.

"Earth-directed CMEs can cause a space weather phenomenon called a geomagnetic storm, which occurs when they funnel energy into Earth's magnetic envelope, the magnetosphere, for an extended period of time," NASA officials said in a description of Wednesday's solar eruption. "The CME’s magnetic fields peel back the outermost layers of Earth's fields changing their very shape. In the past, geomagnetic storms caused by CMEs of this strength have usually been mild."

Many of us take the sun for granted, giving it little thought until it scorches our skin or gets in our eyes. But our star is a fascinating and complex object, a gigantic fusion reactor that gives us life. How much do you know about the sun?
This image, captured by NASA's Solar Dynamics Observatory (SDO) on March 10, 2012, shows an active region on the sun, seen as the bright spot to the right. Designated AR 1429, the spot has so far produced three X-class flares and numerous M-class flares.
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Solar Quiz: How Well Do You Know Our Sun?
Many of us take the sun for granted, giving it little thought until it scorches our skin or gets in our eyes. But our star is a fascinating and complex object, a gigantic fusion reactor that gives us life. How much do you know about the sun?
This image, captured by NASA's Solar Dynamics Observatory (SDO) on March 10, 2012, shows an active region on the sun, seen as the bright spot to the right. Designated AR 1429, the spot has so far produced three X-class flares and numerous M-class flares.
0 of questions complete

Powerful geomagnetic storms can affect communications signals and spark electrical surges in power grids, NASA officials said. They can also supercharge northern lights displays or aurora observers at high latitudes.

According to Spaceweather.com, a website that tracks space weather and skywatching events, the two solar eruptions this week were triggered when vast rope-like filaments of magnetic solar plasma erupted. The CMEs should arrive at Earth in time for weekend aurora watching for stargazers at high latitudes.

"NOAA forecasters expect the CMEs to arrive on August 23-24, possibly sparking geomagnetic storms around the poles," Spaceweather.com stated.

The sun is currently in an active phase of its 11-year solar weather cycle and is expected to reach its peak activity later this year. The current cycle is known as Solar Cycle 24.

Editor's note: If you snap an amazing picture of the northern lights or any other night sky sight that you'd like to share for a possible story or image gallery, send photos, comments and your name and location to Managing Editor Tariq Malik at spacephotos@space.com.

Email Tariq Malik at tmalik@space.com or follow him @tariqjmalikand Google+. Follow us @Spacedotcom, Facebookand Google+. Original article on SPACE.com.