Release Images

Release No.: 2014-26
For Release: Thursday, October 16, 2014 - 2:00pm

Tiny "Nanoflares" Might Heat the Sun's Corona

Sun's transition region

This image from the Interface Region Imaging Spectrograph (IRIS) shows emission from hot plasma (T ~ 80,000-100,000 K) in the Sun's transition region - the atmospheric layer between the surface and the outer corona. The bright, C-shaped feature at upper center shows brightening in the footprints of hot coronal loops, which is created by high-energy electrons accelerated by nanoflares. The vertical dark line corresponds to the slit of the spectrograph. The image is color-coded to show light at a wavelength of 1,400 Angstroms. The size of each pixel corresponds to about 120 km (75 miles) on the Sun.

NASA/IRIS

emission from hot coronal loops

This image from the Atmospheric Imaging Assembly on board NASA's Solar Dynamics Observatory was taken simultaneously with the IRIS observations. It shows emission from hot coronal loops (T > 5 million K) in a solar active region. IRIS observed brightenings occurring at the footpoints of these hot loops. The image is color-coded to show light at a wavelength of 94 Angstroms. The size of each pixel corresponds to about 430 km (270 miles) on the Sun.

NASA/SDO

emission from hot coronal loops

Same as above, with a box showing the field of view of the corresponding IRIS image (top).

NASA/SDO