(PhysOrg.com) -- A large coronal mass ejection (CME) shot off the West (right) side of the sun at 6:24 PM ET on September 21, 2011. The CME is moving away from Earth at about 900 miles per second.
The next morning, an X1.4 class flare erupted from the other side of the sun, peaking at 7:01 AM ET on September 22. The flare came from sunspot N15E88, which is just moving into view as the sun rotates. This flare has caused elevated proton levels on the East (left) side of the sun. Associated with this flare, there was a significant CME, traveling at over 600 miles per second, that began around 7:24 AM ET.
What is a solar flare? What is a coronal mass ejection? For answers to these and other space weather questions, please visit the Spaceweather Frequently Asked Questions page.
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