IRIS Captures Huge Coronal Mass Ejection on Sun
A coronal mass ejection burst off the side of the Sun on May 9, 2014. The giant sheet of solar material erupting was the first CME seen by NASA’s Interface Region Imaging Spectrograph, or IRIS. The field of view for this imagery is about five Earths wide and about seven-and-a-half Earths tall.
Credit: NASA’s Goddard Space Flight Center.
The Interface Region Imaging Spectrograph (IRIS) was launched in June 2013 to observe how solar material moves, gathers energy, and heats up as it travels through a little-understood region in the Sun’s lower atmosphere.
Tracking how material and energy move through this region is a crucial part of understanding the dynamics of the Sun. Such information can help explain what causes the ejection of solar material – from the steady stream of the solar wind to larger, explosive eruptions such as coronal mass ejections (CMEs).
CMEs, often called solar storms or space storms, are gigantic clouds of solar plasma drenched with magnetic field lines that are blown away from the Sun during solar flares and filament eruptions.
CMEs disrupt the flow of the solar wind and produce disturbances that strike the Earth with sometimes catastrophic results.
The first proof of CMEs came from observations made with a coronagraph on the OSO 7 spacecraft between 1971 and 1973.
IRIS must commit to pointing at certain areas of the Sun at least a day in advance, so catching a CME in the act involves some educated guesses and a little bit of luck.
A gigantic CME surged off the side of the Sun on May 9, 2014, and IRIS caught it in unprecedented detail.
“We focus in on active regions to try to see a flare or a CME. And then we wait and hope that we’ll catch something. This is the first clear CME for IRIS so the team is very excited,” said IRIS science team leader Bart De Pontieu from Lockheed Martin Solar & Astrophysics Laboratory in Palo Alto, California.