U.S. begins one month countdown to solar eclipse
Monday, July 24, 2017, 1:46 - As thousands in the United States get ready to view the Aug. 21 solar eclipse through their special glasses, NASA will be using 11 different spacecraft to study the sun's outer atmosphere during the duration of the eclipse, NASA scientist Dr. Michelle Thaller said.
"The moon is blocking out the main bright disk of the sun. So you can actually see what those levels of solar atmosphere are doing. It's called the corona. It's spectacular. And actually the way the corona works is still fairly mysterious," Thaller said on Friday (July 21).
NASA will also fly high-altitude research balloons and airplanes for solar physics and other experiments.
During the eclipse, the moon will pass between the sun and Earth, blocking the face of the sun and leaving only its outer atmosphere, or corona, visible in the sky.
It is the first coast-to-coast total eclipse since 1918.
Total solar eclipses occur somewhere on Earth every year or so, but most cast their shadow over oceans or remote land.
The last total eclipse over part of the contiguous U.S. was in 1979.