By Natalie Simms
It’s been nearly 100 years since the United States has experienced a coast-to-coast total solar eclipse as the sun disappears behind the moon, turning daylight into twilight. It’s an event so rare that all eyes will be watching as the next “Great American Eclipse” takes place Aug. 21, spanning from Salem, Ore., to Charleston, S.C.
By definition, a total solar eclipse occurs when the disk of the moon appears to completely cover the disk of the sun in the sky. According to Space.com, the fact that total solar eclipses occur at all is “a quirk of cosmic geometry.” The moon orbits an average of 239,000 miles from Earth — just the right distance to seem the same size in the sky as the much-larger sun. However, these heavenly bodies line up only about once every 18 months.
“We average seeing about one total solar eclipse every two years,” says Jim Sowell, an astronomer at Georgia Tech. “The next eclipse (in 2019) is primarily in the South Pacific Ocean and cuts across Chile and Argentina. The next nice eclipse across the U.S. is in 2024 but the closest point of totality to Atlanta would be Paducah, Ky. — much further away than this year’s. In 2045, a total eclipse will cross Southwest Georgia, and another one will occur in 2052 over Georgia — but neither of these are close to Atlanta. So, in order for the path of totality to be extremely close to the same spot, it will take about 360 to 400 years to happen again.”
The last coast-to-coast eclipse in the U.S. occurred on June 8, 1918, and spanned a path from near Seattle to Florida, according to the National Eclipse Blog. There was a total solar eclipse in 1970 in the continental U.S. but it did not span coast-to-coast.
What can we expect in our area?
Northwest Georgia and metro-Atlanta are in very close proximity to the area of totality of the eclipse that will be in the northeast corner of the state in Clayton, Ga. Another solar eclipse will not have this same path in our lifetime.
“Northwest Georgia is just outside the area of totality and will see about 97% of the sun disc blocked. It will definitely get darker and will be like night with cooler air,” says Sowell.
If you want to be closer to the path of totality, you should travel north into Tennessee, in fact, Nashville will be in the path of totality. Or you could travel to Northeast Georgia toward Clayton or Rabun County, or into South Carolina. Sowell says even heading to Ellijay or Young Harris will put you closer to the path of totality. Click here for details on exact path across the U.S.
“You definitely need to plan ahead and to the day before to have a spot especially because of traffic…everyone will be trying to get to same area,” he says. “This is a once in a lifetime event…you want to experience it. So make a plan, don’t make it a spur-of-the-moment thing.”
In our area, the eclipse will start around 1 p.m. with the edge of the moon beginning to cover the sun. The time of totality is expected around 2:35 p.m. and lasting about 2.5 to 3 minutes. The final edge of moon will move away from the sun around 4 p.m. Click here for an interactive timing map from NASA.
Local viewing events
Tellus Science Museum in Cartersville has a number of events planned to celebrate the “Great American Eclipse.” David Dundee, the museum’s Astronomy Program manager, will host a special Lunch and Learn program on July 26 at 12:15 p.m. to discuss the event. There also will be a special SCIence FRIday Night event on Aug. 18 at 7 p.m. for the event.
“As the eclipse goes across the continental United States, it is estimated some 22 million Americans will see it on Aug. 21,” says Dundee. “In Cartersville about 97% of the sun will be eclipsed so the lighting will look a bit like twilight at 2:35 pm. Tellus’ observatory will be open (weather permitting), from 1 until 4 p.m. for the partial eclipse observing along with several small telescopes. Inside the museum, views of the partial eclipse will be projected in the Tellus Theater.”
In addition, Dundee and meteorologist Glenn Burns from WSB TV will be broadcasting images of the total eclipse back to Tellus from an undisclosed viewing location near the path of totality.
“You will have a safe place to view the eclipse at Tellus. If the weather does not permit good viewing with our telescope, we will find a NASA satellite to beam in images,” says Dundee. “This is an opportunity to turn people on to the beauty of the sky.”
Warning on eye safety
Just a note of caution, the sun is always dangerous to look at, especially during an eclipse. Never observe the sun without the proper filters.
“Observing the sun is dangerous, don’t stare at the sun as it will damage your eyes,” says Dundee. “And during the eclipse, don’t stare at the sun or at the telescope without proper filters.”
You can purchase safe solar glasses from the Tellus Museum or from a number of online outlets. Click here for details:
You can also make your own pin-hole projection method to view at home. Georgia Tech put together this video with Sowell about the eclipse and safe viewing methods: