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See the Stormy Sun That Produced Yesterday’s Geomagnetic Disturbance [Video]

The views expressed are those of the author and are not necessarily those of Scientific American.

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Sunspot 1302. Credit: NASA/SDO/HMI

A “strong to severe” geomagnetic storm hit Earth yesterday, NASA says, after the sun unleashed a burst of plasma from a turbulent region two days prior.

The region, known as sunspot 1302, has sent forth a few blasts of energy called solar flares, including a flare and an accompanying belch of plasma called a coronal mass ejection (CME) on September 24. The CME reached Earth two days later and impacted the planet’s magnetic shielding, exposing high-altitude satellites to charged particles and magnetic fields, according to NASA. The CME’s arrival also produced low-latitude auroras— reports that sightings of the not-so-northern lights were reported in Michigan, New York, South Dakota, Maine and Minnesota.

Aurora photo: Scott Lough via Flickr/Creative Commons License

According to the National Oceanic and Atmospheric Administration’s Space Weather Prediction Center, high-accuracy GPS services were affected by the storm.

An earlier flare from sunspot 1302 was more powerful but did not aim a blow at Earth—the X1.9-category flare captured on the video below by NASA’s Solar Dynamics Observatory erupted about three hours before the M-class, or medium-size, flare accompanying the CME. X is the most powerful class of flare, and the numerical suffix indicates the relative brightness of the flare within that class. (An X9 is the brightest classification on the scale.)

Video credit: NASA/SDO/GOES

About the Author: John Matson is an associate editor at Scientific American focusing on space, physics and mathematics. Follow on Twitter @jmtsn.

The views expressed are those of the author and are not necessarily those of Scientific American.

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  1. 1. Queyras 5:15 pm 09/27/2011

    The northern lights were seen last night as far south as Michigan, New York, South Dakota and Maine in the United States, and also from Europe and New Zealand. It was the strongest geomagnetic storm since October 2003.
    A HD video of what the northern lights look like during a strong geomagnetic storm as we had yesterday can be seen at

    Link to this
  2. 2. verdai 8:52 pm 10/4/2011

    Our eyes have seen the glory.

    Link to this

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