For the first time in 99 years, a total solar eclipse will cross the entire nation Aug. 21. A total solar eclipse occurs when the sun is completely obscured by the moon. The lunar shadow enters the United States near Lincoln City, Ore., at 9:05 a.m., PDT. Totality, where the moon completely covers the sun, begins in Lincoln City around 10:16 a.m., PDT. During totality, there will be up to two and a half minutes of darkness. The G-III aircraft was modified with upgraded windows and communications equipment to enable high-definition video to be streamed to NASA TV during the eclipse enabling citizen science. The aircraft will be flying at 25,000 feet over the coast of Oregon, near Lincoln City during the eclipse on Aug. 21, 2017.