A rare super bloodmoon will appear Sunday evening, between 9 p.m. and 11 midnight. Credit: Courtesy of TNS

A rare super bloodmoon will appear Sunday evening, between 9 p.m. and midnight. Credit: Courtesy of TNS

This Sunday evening, the moon over Ohio State’s campus will appear a shade slightly closer to scarlet than its usual gray.

Between 9 p.m. and midnight, the night sky will feature a lunar eclipse and a supermoon, an occurrence that only happens about every 33 years. The last supermoon lunar eclipse occurred in 1982.

As the Earth passes between the sun and moon during the lunar eclipse this evening, the moon will also make its closest orbital pass to Earth. The combination of events causes a deep red hue to be reflected off the moon. The result is a super bloodmoon.

OSU’s Astronomical Society is holding an event on the Oval Sunday at 9 p.m. for curious students to stop by, observe the rare event and ask a few questions.

Andrew Zitnik, co-vice president of the Astronomical Society, said that 2015 has been a special year so far, with three bloodmoons having already occurred, but Sunday night’s bloodmoon will be the last of the year, as well as the largest.

“It’s definitely a really cool event,” he said. “It’s all just special circumstances of geometry, just one of these natural things that happen every once in a blue moon.”

A supermoon, also called a “perigee moon,” is when a full or new moon occurs closest to the fall equinox, and is at its closest approach to the Earth on its elliptical orbit.

The close proximity results in the moon appearing brighter and larger — up to 14 percent larger in diameter — than normal, according to a post on NASA’s Tumblr. A supermoon eclipse is when a lunar eclipse coincides with the appearance of the supermoon.

The Astronomical Society will have several telescopes available on the Oval for students hoping to get a closer look. Zitnik, a third-year in astronomy and physics, said that although the event will be clearly visible by the naked eye, the telescopes will afford observers with greater detail of the reddening effect.

“It’s something that is very special,” he said. “I’d definitely encourage anybody to show up because you’re going to see a huge moon, and it’s going to be red, and that’s pretty cool.”

Richard Pogge, astrology professor and vice chair of instrumentation faculty, said lunar eclipses have been important astronomical events for centuries, and might have contributed to the way the Earth’s position in the solar system is seen today.

“The moon is moving into the Earth’s shadow, and the size of that shadow is bigger than the moon, about two to three lunar diameters larger,” Pogge said. By measuring the time it took to pass through, Aristarchus of Samos, an ancient Greek astronomer who theorized that the Sun is center of the universe, was able to tell the moon’s size and distance from the Earth, he added.

Pogge said he expects the event will be easy to see with the expected clear weather on Sunday.

Michael Huson contributed to this article