To experience a total solar eclipse, you have to be in the right place at the right time—and that can be harder than it sounds. The path of totality, the area on Earth where it’s possible to see the moon block the sun completely during an eclipse, can be thousands of miles long but less than 100 miles across. And even the longest eclipses don’t last: the moon completely blocks the sun for no longer than seven and a half minutes, and in some cases only two or three minutes. Earth may be just a tiny dot in the vastness of space, but the odds of finding yourself in a place on that dot where a total solar eclipse is visible at the time when it’s actually happening are even smaller. It’s not surprising that most people have never seen a total solar eclipse in person—in fact, the entire continental United States hasn’t seen one since 1979, so most Americans under the age of 38 haven’t even had the chance to see one in their own country.
A total solar eclipse occurs when the moon passes between Earth and the sun. Light from the sun is blocked by the moon, casting a shadow on Earth. From our perspective on Earth, the moon looks like a black disc sliding across the sun, blocking it out completely for a few minutes. The conditions necessary for a total solar eclipse don’t happen very often: Earth, the moon, and the sun must be in perfect alignment for the moon to completely block the light of the sun.
Here at the Exploratorium, we’ve been livestreaming total solar eclipses since 1998 and have sent teams as far away as China, Turkey, and Micronesia to chase these phenomena and share them with the world. So, what’s it like to see a total solar eclipse in person? “Damned if it didn't look just like a hole in the sky. Kind of impossible, but there it was, blacker than black,” says Exploratorium emeritus Editorial Director Ruth Tepper Brown. Many viewers wax eloquent about the colors of the eclipse: the gray of the dimming sky, the red-orange of sunset all around, the literally eye-burning brightness of the corona, the black of the moon’s silhouette sliding across the sun.
“It begins with a gradual darkening of the sky that progresses to an eerie gray,” says Exploratorium emeritus Senior Science Writer/Editor Judith Brand. “The moment when the last crescent of sunlight vanishes is unnerving . . . Then suddenly the sun’s corona bursts forth–a shimmering halo of light that seems to surround a black hole in the sky.” David Baron, author of the book American Eclipse, agrees: “The main thing is the solar corona—it’s a view you can have at no other time. Seeing the sun is a paradox—only when it’s hidden can you really see it . . . The corona is spectacularly beautiful.”
One thing almost everyone agrees on: Total solar eclipses are weird, in a way that our instincts find unsettling. When the sky goes dark and a warm day goes cold, something feels out of place. “Deep in my body, there is a knowledge that the sky should not go so dark that stars come out in the middle of the day,” says Exploratorium Senior Scientist Paul Doherty. Ruth Brown agrees: “The thing I will never forget is, essentially, how weird it was . . . It was the middle of a hot day, which your brain knows, even as it starts to get dark and cold. Birds stop singing. In the minutes leading up to totality, it got quieter and quieter.”
Perhaps it shouldn’t be surprising that we find this front-row seat for the motion of the solar system unnerving; after all, it reminds us of our tiny place in this vast, empty universe. Exploratorium Multimedia Developer Amaris Blackmore notes, “It made me feel very small and hyperaware that we're just tiny specks of life rotating around a larger, more powerful star.” Adds Baron: “What really struck me at my first eclipse was: I could see the sun and the planets at the same time. It was as if I’d left the solar system and was looking back. I saw Venus, Mercury, and Jupiter in a line, with the sun there between them, and it all made sense. And I’m a part of it; I felt this marvelous, grand, deep, visceral connection to the universe . . . I felt puny, but also part of a grand, enormous thing.”
Watching a solar eclipse alone may be powerful—but watching one in a crowd seems to amplify its effects. “The most surprising thing for me was the group experience,” says Exploratorium Multimedia Specialist Rick Danielson. “Before the eclipse, . . . it didn't cross my mind that I would be swept up in the crowd's jubilation and excitement as well.” Blackmore agrees: “I will never forget the excited sounds of the crowd around me. As it got closer to totality, the energy of the people around me got more intense—it felt a lot like an audience just before a big star gets on stage . . . no pun intended.”
Total solar eclipses are relatively rare, but the chance to see one in the United States is approaching: on August 21, 2017, a total solar eclipse will be visible in a narrow band extending from Oregon all the way to South Carolina. Can’t make it to the path of totality? The Exploratorium can help: we’ll be livestreaming it from sites in Oregon and Wyoming. You can watch from wherever you are through our website and our Total Solar Eclipse app for iOS and Android. Join us for this fascinating, unnerving, awe-inspiring event and get a sense of your own place in the universe.