Today marks an exciting day for millions across North America, as they gear up to witness the spectacular total solar eclipse, a sight that won't return to the U.S. for another two decades.
A solar eclipse happens when the Moon moves between the Earth and the Sun, briefly blocking the sunlight. In the U.S. the path of totality, when the moon blocks the sun's light entirely is expected to occur for more than 100 miles wide across 15 states, while the rest of the nation will have a chance to see at least a partial eclipse.
