Obviously the solar eclipse of August 21, 2017, occurs on August 21, 2017! That’s a Monday in many places, the first day of the new school year.It takes about 90 minutes for the Moon’s dark shadow to cross the country, starting around 10:15 am Pacific time on the West Coast and ending around 2:45 pm Eastern time (11:45 am Pacific time) on the East Coast. When you hear someone say, “the total eclipse lasts 90 minutes,” that’s what they mean. But that could be misleading: At any given location within the path of the Moon’s shadow, the total eclipse lasts at most 2 minutes 40 seconds — don’t be late.