Solar expert visiting Dayton explains eclipse science, says 'We really lucked out'

Apr. 8—Monday's solar eclipse was incredible because the sky was very clear and observers could see the darkness of the moon and the bright white light of the sun's corona, said Justin Kasper, chief of technology at BWX Technologies and a professor of space science at the University of Michigan.

The sky turned from blue to black, the air became colder as a breeze swept through and birds started singing and settling down, thinking it was nighttime, said Kasper, who watched the eclipse with family members, from the backyard of his sister's home in Oakwood.

When the sun got down to a sliver, there was a bright flash of white light in one spot that looked like a diamond, Kasper said.

"You could see the chromosphere, which is kind of the lower atmosphere of the sun (that was) reddish, purple, sticking out around moon," he said. "There was a bright red filament kind of poking out to the south of the moon that was really awesome."

Kasper, who lives in Washington, D.C. and has worked on NASA missions that study the sun in space, is the brother of Hannah Kasper Levinson, who is an art educator in Dayton. He was in town Monday to watch the eclipse. Kasper was one of the principal investigators with the Parker Solar Probe, which is the first spacecraft to fly through the sun's upper atmosphere.

During Monday's eclipse, the sun's corona was sticking out in every direction, he said, and rays jutted out at different distances. Kasper said the scene looked quite a bit like what little kids draw, with sun rays shooting out from the sun.

"Everyone around us was like, 'Ooh,' at the same time," he said.

Kasper said as an astronomer, he knew how things would unfold. But he said it was very special to see it actually happen.

The corona, which is Latin for "crown," is the sun's atmosphere, which is about 1 million degrees Celsius. That's far hotter than the sun's surface.

During the last total eclipse in the U.S. in 2017, the sun was nearing solar minimum, which meant it had the least sunspots, and the sun was quiet. Today, the sun was in solar maximum, meaning it was very active and there were different jets and materials coming off at different speeds, Kasper said.

The red prominence that observers could see on the southern part of the moon was an arc of plasma probably 1,000 times the size of Earth, he said.

Dayton probably was one of the better places in the nation to watch the eclipse, since several other U.S. states in the path of the totality had storms and cloudy weather, Kasper said.

"We really lucked out," he said. "Like 9 minutes before totality, one cloud passed over the sun. We were like, 'Keep going, keep going.' "

The next solar eclipse in Ohio won't take place until 2099. But Kasper said it's possible that Ohioans won't have to wait that long to see other rare phenomena in the sky, like a passing comet or a supernova.

Kasper described eclipse totality as seeming like the sun is setting in every direction all at once — "night kind of appears above you and descends down to the horizon in every direction," he said.

The sun's corona is unstable, and this instability can lead to solar flares and space weather that can damage satellites, injure astronauts and disrupt life on Earth, Kasper said. The Parker Solar Probe spacecraft dips into the corona roughly every three months.

The probe emerged from the corona a few days ago, after taking a variety of measurements.

Scientists will be able to compare detailed photographs of today's eclipse with information gathered by the probe. Scientists hope that studying the sun's atmosphere will help them find ways to predict space weather.

Kasper said he has witnessed partial eclipses on multiple occasions, but this was the first time he got to see a total eclipse with his own eyes.

Kasper watched the 2017 eclipse in Ann Arbor, Michigan. Even though Michigan was not in the path of totality, Kasper said it was still a very special experience.

Total solar eclipse in Ohio

Ohio today is seeing a total solar eclipse for the first time since 1809. Our complete coverage: — —LIVE UPDATES: What our reporters are seeing throughout the region — —EVENTS: What's happening today in southwest Ohio — —TIMING: What time is the eclipse? — —LENGTH: How long will the eclipse last? — —VISITORS: How businesses are trying to cash in — —PHOTOS: How to photograph the eclipse — —HISTORY: What happened in the total solar eclipse of 1806? — —SIGN UP: Get the news of the day delivered to your inbox every morning with our free Morning Briefing newsletter. — —SUBSCRIBE: Like what you see? Explore all special offers here