“On Jan. 28, 2014, NASA’s Interface Region Imaging Spectrograph, or IRIS, witnessed its strongest solar flare since it launched in the summer of 2013. Solar flares are bursts of x-rays and light that stream out into space, but scientists don’t yet know the fine details of what sets them off.
IRIS peers into a layer of the sun’s lower atmosphere just above the surface, called the chromosphere, with unprecedented resolution. However, IRIS can’t look at the entire sun at the same time, so the team must always make decisions about what region might provide useful observations. On Jan. 28, scientists spotted a magnetically active region on the sun and focused IRIS on it to see how the solar material behaved under intense magnetic forces. At 2:40 p.m. EST, a moderate flare, labeled an M-class flare — which is the second strongest class flare after X-class — erupted from the area, sending light and x-rays into space. “