August 21st, 2017, will mark the first time this century, and the first time since 1979, that a total solar eclipse will cross the contiguous (lower 48) United States (Alaska had its turn in 1990; Hawaii in 1991). And for the very first time, the shadow track — better known as the “path of totality” — will sweep only over the United States and no other country.
Many Americans taking full advantage of this event’s close proximity to their homes will have a golden opportunity to witness firsthand one of the most beautiful and most exciting of nature’s sky events. The total eclipse will be seen by an estimated 12 million people who fortuitously live within the totality path. However, the number of people who are within just one day’s drive of the totality zone is probably around 200 million.
Not since 1970 has there been an opportunity to see a total solar eclipse in such easily accessible and widespread areas of the United States. There have been a couple of limited opportunities, such as in 1972 (Quebec and the adjacent Canadian Maritime Provinces) and 1979 (the Pacific Northwest and Northern Plains), but the areas of visibility were either limited or somewhat difficult to reach. And not until April 2024 will there be another opportunity comparable to that offered on Aug. 21, 2017.