The Great American Eclipse Experience: Fourth in a series of articles on the Great American Eclipse of 2017
On Aug. 21, the moon will pass between the sun and earth causing a total solar eclipse. During this time, the moon’s shadow will extend down to the earth projecting a 70-mile wide spot of shaded darkness. For those deep inside the moon’s shadow they will see the sun completely blocked out by the moon.
In a short span of roughly 90 minutes, the moon’s shadow will drag across the landscape, starting in Oregon, passing through the central United States, and heading off the coast line of South Carolina. The narrow band traced out by the moon’s shadow is known as the path of totality.
Dubbed the Great American Eclipse, this is the first time since 1979 that a total solar eclipse will be viewable from anywhere in the continental United States. It also marks the first time in the nation’s history that the path of totality will be exclusive to America.
With the popularity of social media, an estimated 12 million people living within the path of totality, and another 220 million only a few hours drive away, some expect the Great American Eclipse to become the most shared event in history.
South Carolina is expected to see the largest influx of visitors. South Carolina is the closest proximity to totality for most anyone living along the eastern seaboard. It is also home to a number of viewing parties, ranging from Clemson, Greenville, Columbia, Charleston and Georgetown.
For those observing the solar eclipse in the Georgetown area, the moon will begin to edge across the sun, forming a partial solar eclipse, at 1:17 pm. At 2:46 totality begins as the moon completely blocks out the sun. Totality will only last for 1 minute and 46 seconds. After totality is over, a partial eclipse will continue until 4:09 p.m. when the moon completely leaves the sun’s disk.
So what is the safest way to view a solar eclipse?
It is never safe to view the sun directly. This is also true during any partial solar eclipse, when the moon only blocks out a portion of the sun. Even the smallest sliver of the sun peeking out from behind the moon can cause long term or even permanent eye damage.
The best way to directly view an eclipse is with the use of solar viewing glasses. These are specially made glasses that are manufactured specifically with solar filters, which are hundreds of thousands of times darker than regular sunglasses.
With the popularity of the upcoming Great American Eclipse, solar viewing glasses are readily available on the internet, at local retailers, and through public informational events. When buying solar viewing glasses, it is important to make sure they meet the international standard recommend by NASA. Such glasses have a special ISO 12312-2 designation which is clearly marked somewhere on the glasses.
Cameras, binoculars, and telescopes need their own special filters. Even while wearing recommended viewing glasses it is not safe to look at the sun through any optical device. The magnified sunlight viewed through an optical device can damage the solar viewing glasses and may result in eye damage.
The one exception to never looking directly at the sun is during the brief period of totality. This is when the moon perfectly lines up with the sun. If you are wearing solar viewing glasses, you will know it is safe to take them off when everything has gone completely dark.
During the special moment of totality the sun’s outer atmosphere, known as the solar corona, becomes visible. Normally the sun’s lower layers outshine the much fainter solar corona. It takes an eclipse to see the corona.
The solar corona cannot be missed as long as you take off your viewing glasses during totality. The corona appears as a wispy glow that completely surrounds the blackened sun.
After a few moments of totality everything is undone in reverse. The sun’s limb starts to sneak out from behind the moon, the sky brightens, and everything returns to normal.
It is important to have your viewing glasses back on by the first sign of the sun.
During totality the human eye dilates in response to the darkened sky. At this time it is more sensitive to bright light. To prevent potential eye damage it is important to have the solar viewing glasses back on at the first sign of the sun’s disk.
You can share this once-in-a-lifetime event with friends and family by joining others at eclipse viewing parties. The city of Georgetown and Georgetown County will have viewing locations set up at East Bay Park, Morgan Park, Francis Marion Park, the Harborwalk, Carroll Ashmore Campbell Marine Complex and the Georgetown Airport.
Two buses will run from Georgetown High School and Georgetown Middle School, located at 2400 Anthuan Maybank Drive, to Broad and Prince streets for drop off and pick up, then will ride around to East Bay Park for pick-up or drop off. Two buses will also run from the Hampton Inn, Quality Inn and Baymont Inn & Suites to Broad and Prince streets for drop off and pick up, then will ride around to East Bay Park for pick-up or drop off and then back to the hotels. This will be a continuous service from 9 a.m. until 7 p.m. Last Pick up will be at 7 p.m.
For more information on viewing parties and designated viewing areas, please visit www.gtcounty.org.
With any luck, we will have clear skies. But with clear skies comes the summer heat. If you join in on a viewing party do not forget the sunscreen and water.
If the skies are not clear, do not fret. The next total solar eclipse viewable from the United States will occur on April 8, 2024. Unfortunately, totality for the next eclipse will miss South Carolina. Instead, it will travel from Texas, up through the northeast, and into Canada.
Dr. Louis E. Keiner is an associate professor of chemistry and physics at Coastal Carolina University. He joined the university faculty in 1998 and specializes in physical oceanography, satellite remote sensing, hurricanes and climate change. He also has a passion for photography.