The next eclipse on the horizon will be the total eclipse of April 8, 2024, when the moon will be a bit closer and appear a bit larger. That cosmic display will be seen across large swaths of North America. Its path of totality will pass through at least four Mexican states, Texas, part of the US Midwest, and at least four states in eastern Canada. It will plunge those regions into an eerie twilight for up to four and a half minutes, longer than the August 2017 eclipse that crossed the continental US.
While total and annular eclipses are similar, astronomically speaking, experiencing them can feel very different. During a total eclipse, it takes just 30 seconds for broad daylight to transform into dusk. “It is stunning. Your senses say, ‘Something is wrong.’ You get this visceral feeling in your stomach, the hair on the back of your neck will stand up, you’ll get the shivers. People weep. It’s a moving experience,” says Fred Espenak, a retired astrophysicist at NASA’s Goddard Space Flight Center and coauthor of the upcoming book Totality: The Great North American Eclipse of 2024.
Equipped with the right shades, people can safely watch partial, annular, and total eclipses. Libraries, science museums, and other local institutions often offer free eclipse glasses, and they can be ordered online too. But never use ordinary sunglasses: Those block just half of the light, while eclipse glasses have a thin layer of metal or polymer in them that only allow 1 part in 100,000 of light to pass through, Espenak says. (The American Astronomical Society also provides a guide to eye safety. Look for the ISO 12312-2 international safety standard for filters.)
Phtograph: PATRICK T. FALLON/Getty Images
Eclipse glasses are the easiest viewing devices, but one can also see them other ways, such as through #14 welding glass or with a pinhole camera (or video camera), which projects an image of the eclipse against a screen. Standing with your back to the sun and holding your fingers together in a waffle pattern can also project an image of the eclipse onto the ground, and so can the dappled light falling through leafy trees. NASA will also livestream video of the eclipse.