Solar Corona (image) Harvard-Smithsonian Center for Astrophysics Caption These photos of the solar corona, or million-degree outer atmosphere, show the improvement in resolution offered by NASA's High Resolution Coronal Imager, or Hi-C (bottom), versus the Atmospheric Imaging Assembly on NASA's Solar Dynamics Observatory (top). Both images show a portion of the sun's surface roughly 85,000 by 50,000 miles in size. Hi-C launched on a sounding rocket on July 11, 2012 in a flight that lasted about 10 minutes. The representative-color images were made from observations of ultraviolet light at a wavelength of 19.3 nanometers (25 times shorter than the wavelength of visible light). Credit NASA Usage Restrictions None Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.