Four images of a filament on the sun from August 31, 2012 are shown here in various wavelengths of light as captured by NASA’s Solar Dynamics Observatory (SDO). Starting from the upper left and going clockwise they represent light in the: 335, 171, 304 and 131 Angstrom wavelengths. Since each wavelength of light generally corresponds to solar material at a particular temperature, scientists can compare images like this to observe how the material moves during an eruption. Credit: NASA/SDO/AIA/GSFC
On August 31, 2012 a long filament of solar material that had been hovering in the sun's atmosphere, the corona, erupted out into space at 4:36 p.m. EDT. The coronal mass ejection, or CME, traveled at over 900 miles per second. The CME did not travel directly toward Earth, but did connect with Earth's magnetic environment, or magnetosphere, with a glancing blow. causing aurora to appear on the night of Monday, September 3.
