HARRISBURG, Pa. (WHTM) – Today’s the day the U.S. will experience its first coast-to-coast total solar eclipse in 99 years.
A solar eclipse happens when the moon casts a shadow on Earth, fully or partially blocking the sun’s light in some areas. The path of totality – where the sun will be completely obscured by the moon – begins in Oregon and ends in South Carolina, but everyone else in North America will be able to experience a partial eclipse.
In central Pennsylvania, the moon will obscure 70-80 percent of the sun.
This will be the first total solar eclipse visible in the continental United States in 38 years, but in 1979, the path of totality was far from Pennsylvania. The total eclipse was visible in Oregon, Washington Idaho, Montana and North Dakota. Before that, in 1970, a total solar eclipse skirted the Atlantic coastline from Florida to Virginia.
The last time a total solar eclipse swept the whole width of the U.S. was in 1918.
The partial eclipse in central Pennsylvania will begin at approximately 1:15 p.m. The sun will be most obscured around 2:40 p.m., and it’ll end around 4 p.m.
WATCH ON TV
If clouds obscure your view or you’re stuck indoors, ABC News will present a two-hour special, “The Great American Eclipse,” beginning at 1 p.m., with correspondents reporting from viewing parties across the country.
WATCH A LIVE STREAM
You can watch ABC’s live coverage here from 1 p.m. to 3 p.m.
Or, you can watch NASA’s eclipse coverage as it follows the totality across the country from a series of 50 cameras attached to balloons at elevations of up to 100,000 feet.
If you’re headed outdoors, remember that the only safe way to look directly at the uneclipsed or partially eclipsed sun is through special-purpose solar filters such as “eclipse glasses” or hand-held solar viewers. Homemade filters or ordinary sunglasses, even very dark ones, are not safe.
If you have an old welder’s helmet and plan to use it, make sure you know the filter’s shade number. If it’s less than 12, NASA says don’t even think about it. Many people find the sun too bright even in a Shade 12 filter, and some find the sun too dim in a Shade 14 filter.
An alternative method for safe viewing is pinhole projection. You can make a simple eclipse projector with almost any cardboard box, paper, tape and aluminum foil.
USE A MIRROR
Another safe viewing alternative recommended by NASA is to slide a mirror into an envelope with a ragged hole about 5/8 inch cut into the front. Point the mirror toward the sun so that an image is reflected onto a screen about 15 feet away. The longer the distance, the larger the image.
Remember to look at the screen, not the mirror.
USE YOUR HANDS
You can create pinhole projections with your fingers. Start by crossing your outstretched, slightly open fingers of one hand over the outstretched, slightly open fingers of the other. With your back to the sun, look at your hands’ shadow on the ground. The little spaces between your fingers will project a grid of small images on the ground, showing the sun as a crescent during the partial phases of the eclipse.
USE A TREE
If you look at the shadow of a leafy tree during the partial eclipse, you’ll see the ground dappled with crescent suns projected by the tiny spaces between the leaves.
If you miss the eclipse, you’ll have to wait seven years to see another one, but April 8, 2024, promises an even better show in Pennsylvania. In most of the state, the moon will obscure 90-95 percent of the sun, and northwestern Pennsylvania is in the line of totality.