Astronomy Picture of the Day
Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.
2016 April 12
Explanation: Sometimes, a total eclipse is a good time to eye the Sun. Taking advantage of an unusual juxtaposition of Earth, Moon and Sun, the featured image depicts the total solar eclipse that occurred last month as it appeared — nearly simultaneously — from both Earth and space. The innermost image shows the total eclipse from the ground, with the central pupil created by the bright Sun covered by a comparatively dark Moon. Surrounding the blocked solar disk is thetenuous corona of Sun imaged in white light, easily visible from the ground only during an eclipse. Normally, this corona is hard to track far from the Sun, but the featured montage matches it to false-colored observations of the Sun from NASAand ESA’s space-based, Sun-orbiting, Solar and Heliospheric Observatory (SOHO). Observations like this allow the study of the constantly changing magnetic activity both near and far from the Sun, the same activity that ultimately drives Earth’s auroras.