On August 21st, 2017, the U.S. will experience its first coast-to-coast solar eclipse in 99 years. The eclipse will travel from Oregon to South Carolina, darkening skies and dropping temperatures along the way. Astronomers are already calling it a jaw-dropping, mind-blowing, once-in-a-lifetime event. Why do eclipses tend to cast a spell on the humans who watch them? And what do you need to know about this upcoming event? Discussing the upcoming solar eclipse with Joshua Johnson is David Boboltz, program director at National Science Foundation's Division of Astronomical Sciences, Carrie Black, associate program director at National Science Foundation's Atmospheric and Geospace Sciences Division, Alex Young, associate director for science in the Heliophysics Science Division at NASA's Goddard Space Flight Center and Ernie Wright, visualizer at the Scientific Visualization Studio at NASA's Goddard Space Flight Center.