This image combines two sets of observations of the sun at 10:45 AM EDT, July 12, 2012 from the Solar Dynamics Observatory (SDO) to give an impression of what the sun looked like shortly before it unleashed an X-class flare beginning at 12:11 PM EDT. The image incorporates light in the 171 angstrom wavelength, which shows off giant loops of solar material overlying the middle of the sun over Active Region 1520 where the flare originated. The second set of observations is called a magnetogram, which highlights magnetic fields on the sun. Together these kinds of observations can help scientists understand the magnetic properties of the sun that lead to giant explosions like flares.
GCMD keywords can be found on the Internet with the following citation:
Olsen, L.M., G. Major, K. Shein, J. Scialdone, S. Ritz, T. Stevens, M. Morahan, A. Aleman, R. Vogel, S. Leicester, H. Weir, M. Meaux, S. Grebas, C.Solomon, M. Holland, T. Northcutt, R. A. Restrepo, R. Bilodeau, 2013. NASA/Global Change Master Directory (GCMD) Earth Science Keywords. Version 18.104.22.168.0