Sun ID: 11708

NASA's IRIS Helps Explain Mysterious Heat of the Solar Atmosphere

Released on October 16, 2014

This movie shows succeeding images from NASA’s IRIS of the same area of the sun in different wavelengths. Each image carries information about how fast the solar material is moving, which has shown scientists that a series of loops are twisting in the sun’s lower atmosphere.

Credit: NASA/IRIS/Pereira

NASA's newest sun-watcher, the Interface Region Imaging Spectrograph, launched in 2013 with a specific goal: track how energy and heat coursed through a little understood region of the sun called the interface region. Sandwiched between the solar surface and its outer atmosphere, the corona, the interface region is where the cooler temperatures of the sun's surface transition to the hotter temperatures above. Moreover, all the energy to power the sun's output -- including eruptions such as solar flares and the sun's constant outflow of particles called the solar wind -- must make its way through this region.

In the Oct. 17, 2014, issue of Science magazine, five papers based on IRIS data highlight different aspects of the energy's journey from the sun’s surface through its atmosphere. By looking at various regions of the interface region in unprecedented resolution, the papers offer clues to what heats the corona to unexplained temperatures of millions of degrees, far hotter than the surface of the sun itself, as well as what causes great writhing movement and accelerated particles throughout the solar atmosphere.

NASA’s IRIS, which is able to look at a low layer of the sun’s atmosphere in unprecedented resolution, reveals details in the bright loops seen over the sun’s limb that have never been witnessed before.

Credit: NASA/IRIS/Hansteen

Bright lights in this movie from NASA’s IRIS, represents spots of intense heat — at 200,000 F — that may hold clues to what heats the solar atmosphere to mysteriously high temperatures.

Credit: NASA/IRIS/Peter