MARTIN, Tenn. – On Aug. 21, 2017, West Tennessee was able to experience a near-total solar eclipse, as the path of totality crossed the nation from Oregon to South Carolina, passing just to the east of the Land Between the Lakes area in Tennessee.
In a little more than two weeks, this region will see the show again.
On April 8, the moon’s shadow will again trek across the U.S., this time from Mexico into Texas and up through Maine and Canada. The path of totality will also pass through a more populous area than it did in 2017, enabling more people to see it.
A solar eclipse – either partial or total – happens when the moon passes between the sun and Earth and covers all or part of the sun’s disk. The path of totality is where the moon totally covering the sun’s disk can be seen throughout the day, making a path of several miles in a general west-to-east direction.
Martin will not be in the path of totality for the upcoming eclipse, but it is only about 30 miles outside of that path, enabling the city to see more than 99% obscuration, or covering of the sun’s disk.
From a viewpoint in Martin, the moon will begin to move into the sun’s disk, or “take a bite out of the sun,” at 12:41 p.m. The point of maximum coverage will be right at 2 p.m., and the moon will be out of the sun’s disk at 3:18 p.m.
Dr. Lionel J. Crews, associate professor of physics, said the 115-mile-wide path of totality for the upcoming solar eclipse will be wider than the previous eclipse, which was 70 miles wide.
“Because the moon's orbit is not a perfect circle around the Earth, the distance from the Earth to the moon varies,” he said. “When it is closer to the Earth, it appears larger and, thus, it casts a larger shadow. This will make the area of totality wider and the eclipse last longer.”
The 2017 eclipse was Crews’ first experience with a total solar eclipse, and he said experiencing a total, 100%-coverage solar eclipse does not compare with anything less, even 99% coverage.
“While 99% will still be pretty cool to see, it is vastly different than 100%,” he said. “At 100%, you get all the best effects: seeing the shadow approach from a distance, the air temperature is measurably cooler, bird and insect behavior changes, you can see the atmosphere of the sun (called the corona) and more.”
Crews plans to view the April 8 eclipse from outside of Tennessee to again experience the eclipse within the path of totality.
“I will be traveling to near Sikeston, Missouri, to see this one,” he said. “I was in Draffenville, Kentucky, for the 2017 eclipse. My family and I drove up the Purchase Parkway until we got into the region of totality and pulled off into a Dairy Queen parking lot – ice cream and an eclipse!”
Although this area of the United States got to view solar eclipses twice in seven years, the next solar eclipse in this area won’t arrive until Aug. 12, 2045.
“The moon's orbit, in addition to being not a circle, is also tilted with respect to the Earth's orbit around the sun,” Crews said. “That means that each time the moon's orbit brings it close to the sun in the sky, the orientation can be different.
“In addition, the shadow of the moon is relatively small on the Earth, only covering a tiny swath of land area. So, all it takes is a small change in the orientation to drastically change the location at which the eclipse is visible.”
People who kept their eclipse glasses from the 2017 event may be able to use them for this eclipse, but they should be sure they are good to go before using them.
“Viewing an eclipse isn't inherently more dangerous than looking at the sun when there is no eclipse,” Crews said. “The danger occurs because of our curiosity. We normally quickly avert our eyes when we look at the sun, but during an eclipse, there is a tendency to stare at it.
“It is the staring at the sun that can produce damage to the eye. So just don't stare at it, or don't look at it without eye protection.”
Viewing glasses may be available at stores or special events, but people should check to see if they have been inspected. There was a recall of viewing glasses in Paducah this month because the glasses did not have information indicating that they had been inspected, including the International Organization for Standardization (ISO) number and logo, found inside the glasses.
“You can purchase eyewear online or get it from a store, like the souvenir shop at Discovery Park of America in Union City, but like anything, frauds and fakes are out there,” Crews said. “If you already have some eyewear leftover from the last eclipse, give it a quick test.
“Put it on and glance very briefly at the sun. If it causes any discomfort or leaves a spot in your vision that lasts more than a few seconds, don't use them.”
Solar eclipses are usually preceded or followed by lunar eclipses within two weeks of each other. Usually, one eclipse is strong, while the other associated eclipse is weak.
There will be a penumbral lunar eclipse on March 25, when the full moon passes through the outer part of Earth’s shadow, called a penumbra, Latin for “next to shadow.”
The Earth’s umbra, or shadow, is what makes the moon get dark during a lunar eclipse. The moon passes through the penumbra, then the umbra during a total lunar eclipse. When the moon only goes through the penumbra, it dims but doesn’t get as dark.
“When the moon's orbit is lined up to create a solar eclipse, one half-orbit before or after, it will be somewhat lined up for a lunar eclipse, and vice versa,” Crews said. “As it makes that two-week half-orbit journey, though, it is slowly drifting in alignment. Therefore, the lunar eclipse associated with a solar eclipse will generally not be a very ‘good one’ – perhaps only partial – and vice versa.”
A lunar eclipse happens when the Earth moves between the sun and the moon. Its shadow covers at least part of the moon’s disk, and always happens during the full moon phase.
The Martin Public Library will have a solar eclipse class at 11 a.m. Saturday, April 6. Solar eclipse viewing glasses will be given away at this class while supplies last.
Viewing glasses are available elsewhere in West Tennessee, including the Walmart Supercenter in Martin.
Discovery Park of America in Union City will provide a place to view the eclipse, with food available at Sabin’s Café and Eats and Treats, with solar eclipse viewing glasses available in its gift shop.
Discovery Park of America will also have a Great Eclipse Race, inviting teams of one to four people to take part in a battle of wits against other teams and the eclipse itself.
Participants will work through STEAM puzzles – involving science, technology, engineering, art and math – and collecting the clues needed to win the contest. The first to solve the challenge will win $100.
The race will begin at noon and end when the eclipse ends at 3:19 p.m. Information about the event can be found at https://discoveryparkofamerica.com/event/the-2024-eclipse.