On 21 August 2017 the Moon's shadow crossed the United States from the Pacific to the Atlantic, and millions of people stepped outside to watch day turn into twilight. It was the first total solar eclipse to sweep the full width of the country since 8 June 1918, and the first visible anywhere in the contiguous US since February 1979. Americans called it the Great American Eclipse.

Illustration of a total solar eclipse against a dark space background
A total solar eclipse, when the Moon covers the Sun's bright disc.

The path of totality across the United States

The band of totality, only about 70 miles (115 km) wide at most, reached land on the Oregon coast shortly after 10:15 am local time. From there the shadow raced south-east across fourteen states:

  • Oregon, Idaho, Montana and Wyoming
  • Nebraska, Kansas, Iowa and Missouri
  • Illinois, Kentucky and Tennessee
  • Georgia, North Carolina and South Carolina

Cities inside the path included Salem in Oregon, Casper in Wyoming, Nashville in Tennessee, and Columbia and Charleston in South Carolina, while Kansas City sat right on the edge. The shadow left the US near Charleston, South Carolina, and headed out over the Atlantic.

How long totality lasted

The point of greatest eclipse fell in western Kentucky near Cerulean, between Hopkinsville and Princeton, at about 1:26 pm local time, where totality lasted 2 minutes 40 seconds. The longest totality measured on the ground, 2 minutes 41.6 seconds, was at Giant City State Park, just south of Carbondale, Illinois.

Across the rest of North America, Central America and the northern part of South America, people saw a partial eclipse. Outside the narrow path the Sun never disappears completely, which is why eclipse chasers travel hundreds or thousands of kilometres to stand inside the band. The difference between 99% and 100% coverage is the difference between a dim afternoon and the sight of the solar corona, stars at midday and a 360-degree sunset glow on the horizon.

Watching an eclipse safely

NASA's eclipse safety rules are simple and worth memorising before any trip:

  • Use eclipse glasses or handheld viewers that meet the ISO 12312-2 standard. Ordinary sunglasses, however dark, are not safe.
  • Check viewers before use and throw away any that are scratched or torn.
  • Never look through a camera, binoculars or telescope while wearing eclipse glasses. Optics need their own solar filter fitted on the front.
  • Take the glasses off only during totality, when no part of the bright Sun is visible, and put them back on the moment it reappears.
  • No glasses? A simple pinhole projector casts an image of the Sun onto paper or the ground, with the Sun behind you.

Pack a hat and sunscreen too. The partial phases before and after totality add up to well over two hours, and most people spend that time outdoors.

The next total solar eclipses

North America had to wait less than seven years for the next one. On 8 April 2024 totality crossed Mexico's Pacific coast near Mazatlán, then fifteen US states from Texas to New England, including Dallas, Indianapolis, Cleveland and Buffalo, and passed over Ontario and Quebec. Near Nazas, in Durango, it lasted about 4 minutes 28 seconds.

The next big event is the total eclipse of 2 August 2027, visible from southern Spain, across North Africa from Morocco to Egypt, and over Saudi Arabia and Yemen. For the United States, the next great crossing comes on 12 August 2045, with totality running from northern California through Nevada, Utah, Colorado, Kansas, Oklahoma, Texas and the Gulf states to Florida, then over the Bahamas and the Caribbean. Over the Atlantic near the Bahamas, totality will last just over six minutes.

Book early for any eclipse trip. Hotels inside the path fill up years ahead, and a flexible base lets you drive to clearer skies if clouds threaten on the day.

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