In a little over two weeks, tens of millions of people are expected to take in the rare, total solar eclipse.
To make sure safety isn't overshadowed, cities coast to coast are bracing for crowds and putting emergency plans in place. Seth Lemon has more from New York.
South Carolina officials are urging residents and visitors to get their plan in place for viewing the total solar eclipse on Aug. 21.
"Our overriding concern is safety," said Charleston County EMS Director David Abrams. "Make sure you bring hydration and medications. Make sure you have appropriate eye wear when looking at the sun.
South Carolina is on the coast-to-coast swath where people will be able to watch as the moon completely blocks the sun.
Authorities are expecting thousands to flood to parks and other open spaces to get a glimpse of the spectacle, using protective eyewear.
Traffic will be heavy and cell phone service will be stretched to its limits.
"This is the first total solar eclipse in the U.S. in the cellular era, so some of the impacts may not be known ahead of time," said Bill Tunic, Charleston County Director of Telecommunications.
But you don't have to live near the line of totality to witness this astronomical wonder.
Americans who live outside the path of complete darkness will still be able to experience quite a phenomenon.
"You should definitely watch it," said Dr. Jackie Faherty, astronomer at American Museum of Natural History. "Just because you're not in the path of totality doesn't mean the experience won't be kind of mind boggling as it's happening."
This will be the first coast-to-coast eclipse in 99 years. A once-in-a-lifetime spectacle shared across the entire United States.