Despite the wealth of knowledge we’ve amassed about our nearest star, there is still a lot we don’t know about the corona — the uppermost region of the solar atmosphere. Previous observations of the outer corona have indicated that the region is smooth and lacking in small-scale structure — but is it really?
To learn more about the outer corona, a team led by Craig DeForest (Southwest Research Institute) analyzed images from a special observing campaign by NASA’s Solar Terrestrial Relations Observatory-A (STEREO-A). In a departure from its typical observing mode, STEREO-A increased its imaging cadence by a factor of four and exposure time by a factor of six.
Using careful image-processing techniques, DeForest and collaborators extracted hidden details from the STEREO-A images.