Why a total solar eclipse is such a big deal
How solar and lunar eclipses work. Note: This is an update of a video we published in 2015. Sources: Getty Images https://www.amazon.com/Totality-Great-American-Eclipses-2017/dp/0198795696/ref=sr_1_1?ie=UTF8&qid=1500557252&sr=8-1&keywords=totality
