
Skywatchers will see a rare celestial sight during the Aug. 21 total solar eclipse: the sun’s shimmering outer atmosphere, known as the corona. What will it look like? Astronomers worked their magic to give us a glimpse.
The corona is more than just a fuzzy halo: The superheated gas that makes up the sun’s outermost layer tends to follow the patterns of magnetic force that arc around the sun.
To come up with their preview of the corona, researchers at the National Solar Observatory in Arizona modeled the sun’s magnetic field as of July 25, which was 27 days in advance of the solar eclipse. That’s important, because it takes the sun 27.2753 days to make a complete rotation.