Heads up: Solar eclipse to pass over Sandusky

SANDUSKY — No, the sun won't set early on Monday: The moon will just pass between it and the Earth to block out some of the daylight.This rare astronomical phenomenon is known as a solar eclipse. But what is an eclipse?Glenn Tiede, a senior lecturer with Bowling Green State University's physics and astronomy department, offered an explanation. "The moon orbits the Earth, and the Earth orbits the sun, but they don't always cross the same plane in the sky," Tiede said. "It's only when these three bodies line up directly that an eclipse occurs."Despite being situated roughly 93 million miles away, the sun appears to be the same size as the moon in the sky. That distance is like driving roundtrip from New York to Los Angeles 16,600 times. The moon casts a shadow on the Earth when it moves between the Earth and the sun, blocking light and creating a solar eclipse. An eclipse doesn't occur every month, however, because the moon orbits the Earth on a slight tilt. As a result, the moon's shadow is usually cast either above or below the Earth, Tiede said. The last time such an eclipse passed over the continental U.S. was Feb. 26, 1979. "Historically, an eclipse is a big deal," Tiede said. "But, scientifically, the eclipse itself isn't that interesting anymore. Back during the Renaissance (from 1300 to 1700), it was a big deal because it verified that we knew how gravity works. In order to predict an eclipse, you have to understand gravity."A total eclipse offers those on Earth a chance to view the sun's corona, the bright and fiery outermost portion of the sun's atmosphere. This area of the sun is usually outshined and isn't visible on Earth. But with the moon blocking out most of the sun during a total eclipse, the corona becomes visible. Historically, eclipses offered scientists golden opportunities to study the sun. For instance, Albert Einstein used a solar eclipse in May 1919 to test his General Theory of Relativity, which sought to explain gravity. His theory, which is largely accepted by today's scientific community, proposes that gravity is not a force but a distortion of spacetime. The theory suggests massive objects, like stars, produce enough gravity to distort objects in space, including light, according to NASA. Einstein used an eclipse to track light radiating from other stars behind the sun. Today, scientists have other means of studying the sun with satellites and spacecraft. Two or three times a year, NASA's Solar Dynamics Observatory observes the moon traveling across the sun, blocking its view. While this obscures solar observations for a short while, it offers the chance for an interesting view of the shadow of the moon. The moon's crisp horizon can be seen up against the sun, because the moon does not have an atmosphere. (At other times of the year, when Earth blocks SDO's view, the Earth's horizon looks fuzzy due to its atmosphere.) Things to know• The partial eclipse will be visible in northern Ohio between 1-4p.m. Monday• About 80 percent of the sun will be blocked from view in northern Ohio, whereas it'll be 100 percent blocked out in other portions of the country• The sun is 400 times wider than the moon, but the moon is 400 times closer to the Earth• Staring at an eclipse without proper protection can permanently damage your eyes• The next eclipse visible in the U.S. will occur on April 8, 2024.Source: NASAReach reporter Patrick Pfanner at pfanner@sanduskyregister.com, follow him on Twitter @PatPfanner and follow the Register at Facebook.com/SanduskyRegisterThis photo provided by Bob Baer and Sarah Kovac, participants in the Citizen CATE Experiment, shows a "diamond ring" shape during the 2016 total solar eclipse in Indonesia. For the 2017 eclipse over the United States, the National Science Foundation-funded movie project nicknamed Citizen CATE will have more than 200 volunteers trained and given special small telescopes and tripods to observe the sun at 68 locations in the exact same way. The thousands of images from the citizen-scientists will be combined for a movie of the usually hard-to-see sun's edge. (R. Baer, S. Kovac/Citizen CATE Experiment via AP)