Questions and answers about the total eclipse,

Q. What’s a total solar eclipse?

A. When the moon passes between Earth and the sun, and scores a bull’s-eye by completely blotting out the sunlight, that’s a total solar eclipse. The moon casts a shadow on our planet. NASA reports there will be a 70-mile-wide “path of totality” where the moon will block 100 percent of the sun. Dead center of the path of totality is where sky gazers get the full treatment, and can see the corona, the famous visual of the halo of light around the dark disk of the moon. A partial eclipse will be visible along the periphery. Keep in mind: Clouds could always spoil the view.

Q. What’s the path on Aug. 21?

A. The path of totality will begin near Lincoln City, Oregon, as the lunar shadow makes its way into the U.S. This path will be 60 to 70 miles wide; the closer to the center, the longer the darkness. In this case, the total eclipse will last up to 2 minutes and 40-plus seconds in the middle of that path. Totality will cross from Oregon into Idaho, Wyoming, Nebraska, Kansas, Missouri, Illinois, Kentucky, Tennessee, Georgia, North Carolina and, finally, South Carolina. It will also pass over tiny slivers of Montana and Iowa. The eclipse will last longest near Carbondale, Illinois: two minutes and 44 seconds. The biggest cities in the path include Nashville; and Columbia and Charleston, South Carolina

Q. When’s the next one? A. If you miss the Aug. 21 eclipse — or get bitten by the eclipse bug — you’ll have to wait seven years to see another one in the continental U.S. The very next total solar eclipse will be in 2019 , but you’ll have to be below the equator for a glimpse. We’re talking the South Pacific, and Chile and Argentina. It’s pretty much the same in 2020. For the U.S., the next total solar eclipse will occur on April 8, 2024 . The line of totality will cross from Texas, up through the Midwest, almost directly over Indianapolis, Cleveland and Buffalo, New York, up over New England and out over Maine and New Brunswick, Canada.