Late last month, NASA's Interface Region Imaging Spectrograph (aka IRIS) witnessed the strongest solar flare it's glimpsed since its launch last year.
IRIS spacecraft was deployed last June to observe the little-explored lower layers of the Sun's multi-level atmosphere in unprecedented detail. Since then, it's turned up never before-seen-images of the Sun's chromosphere, the so-called "interface region" that serves as an energy conduit between the Sun's low-level photosphere and its outer corona, but it's also recorded a number of solar flares. This one, which it spied on January 28th, was the biggest it'd seen yet:
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.
IRIS studies the layer of the sun's atmosphere called the chromosphere that is key to regulating the flow of energy and material as they travel from the sun's surface out into space. Along the way, the energy heats up the upper atmosphere, the corona, and sometimes powers solar events such as this flare.