Total solar eclipses cast an eerie darkness over the day, but astronomers say that's an ideal time to study the sun. Jeff Hall is an astronomer and sun expert at Lowell Observatory. He says when the sun’s brilliance is blocked out by the moon, other solar features appear.
“Historically, eclipses played a significant role in helping us develop our understanding of the sun’s atmosphere because the very thin outer layers of the sun’s atmosphere—what we call the chromosphere and the corona—are up there every day but you can’t see them because the dazzling light that illuminates the world, which comes from the photosphere, washes it all out,” says Hall.
Hall studies sunspots. He wants to understand more about how violent solar storms affect Earth's climate.
“A solar storm can even knock out power grids if it’s strong enough. That’s happened before, not very often. And, of course, it’s useful to know that because today we are so dependent on hardware in orbit, right, for communications and location, and the like. So, understanding how our star behaves is a real practical relevance and importance,” says Hall.
Astronomers will study the sun during the total solar eclipse on Aug. 21, when a 70-mile wide shadow moves across the United States from Oregon to South Carolina.