A convergence of events will combine Sunday night to produce something seen only five times over the past century — the total eclipse of a “supermoon.”
If the skies are clear, viewers in the Baton Rouge area will get to watch the moon on its orbit closest to the Earth slowly turn red as light from the sun filters through the Earth’s atmosphere. Because it is closer, the moon will appear larger in the night sky as Earth’s shadow creeps across the moon until it completely covers it.
In ancient times, the phenomenon would be a cause for fear, dread and superstition, but Sunday night it will just be a great celestial show starting shortly after 8 p.m. and unfolding over the course of an hour.
“It’s kind of weird and primal,” said Brad Schaefer, professor of physics and astronomy at LSU. “This is beautifully placed right in the evening.”
The last partial lunar eclipse visible from Louisiana occurred in April 4 but started at 5:15 a.m. which was a little early for some viewers. Sunday evening’s total eclipse, weather permitting, will be the last time such a phenomenon will be visible from Louisiana until March 20, 2018. The next time a supermoon combines with a total lunar eclipse will be 2033.
Part of the fun is not knowing exactly what the eclipse will look like since the color will depend on what is going on in Earth’s atmosphere at the time.
“My suspicion is that it will be a relatively bright and relatively red moon,” Schaefer said.
Sometimes, the total eclipse will be very dark red or dark if there has been volcanic activity that has thrown material high into the atmosphere. With no known major eruptions, that’s not likely to be the case this time unless there was something going on in a part of the world that wasn’t noticed, he said.
When the total eclipse stage is reached around 9:12 p.m. the moon will look red because of the sunlight passing through the atmosphere directing all Earth’s sunsets and sunrises onto the moon’s surface.
“When the moon is completely immersed, that’s when you start to see color,” said Christopher Kersey, manager of the Highland Road Park Observatory. “We’re lucky. It’s only the eastern United States that is going to see the whole thing.”
The eclipse will continue with less and less shadow until the eclipse is visibly over by 11:28 p.m.
Eclipses through history have at times educated, scared and even saved people.
Lunar eclipses gave the ancients a chance to see the form of the Earth and deduce that not only was the Earth round, but even got very close to determining the size of the Earth and moon, he said.
“You can see the shape of the Earth because you can see the shadow,” he said. “It’s the same way the ancients knew about what shape the Earth was.”
It’s a myth invented by Washington Irving that Christopher Columbus sailed from Europe amid fears that the world was flat and they might fall off the edge if they weren’t careful.
With a few mathematical steps, ancient people also figured out the distance from the moon to the Earth. “And you (the ancient people) probably never left the valley you were born in,” Schaefer said.
At the same time, many old cultures identified the moon as a deity, so a lunar eclipse was a portent for bad things. In Southeast Asia, the eclipse was seen as the fault of demons, while in Central America it was the jaguar eating the moon who would soon come down to Earth and keep eating people.
For Christopher Columbus, an old almanac predicting a lunar eclipse let him play a trick on locals in Jamaica where he and his crew were stranded. He told the people that unless they kept him and his men fed, his god would swallow the moon. The lunar eclipse occurred and Columbus got to eat until he was eventually rescued.
“Fortunately for Columbus, the night was clear. Otherwise we may have ended up wondering what happened to Columbus,” Schaefer said.
Other than backyards all over Louisiana, viewing events will be held at LSU from 8:30 to 11:30 p.m. There will be a viewing at the Landolt Astronomical Observatory at the top of the Nicholson Hall, Tower Drive on LSU’s campus, with views through the Alvan Clark Telescope and from 6:30 p.m. to 12:30 a.m. viewings will be held at the Highland Road Park Observatory.
Follow Amy Wold on Twitter, @awold10.