Donald Liebenberg remembers clearly his first total solar eclipse.
It was 1954, and he was a physics major at the University of Wisconsin. Liebenberg and his professors drove a station wagon up a hill in a small town south of Lake Superior and set up their instruments under a clear morning sky. Black flies buzzed around them in the June heat. The moon began its slow creep across the sun, inching further and further until it blocked the light and cast its shadow on Earth. For about a minute, their little spot on the globe was blanketed in darkness.
Liebenberg remembers his second total solar eclipse, on the island of Pukapuka in 1958, just as clearly. And the one after that. And the one after that, and after that, and—the point is, Liebenberg has seen a lot of eclipses. Liebenberg, a physics and astronomy professor at Clemson University, has spent more than 60 years traveling around the world to experience the phenomenon a whopping 26 times. He’s observed eclipses from the ground, on ships in the middle of the ocean, aboard military planes, and, most notably, inside the supersonic Concorde jet as it soared over Earth at twice the speed of sound. He has watched from a desert camp in Libya, a hotel yard in Easter Island, and a bustling city in Turkey. All told, Liebenberg has spent nearly three hours in totality, inside the darkest part of the moon’s shadow. It’s a world record among eclipse chasers—or “umbraphiles,” as they’re called, for their love of the shadow.
But Liebenberg isn’t traveling for the August 21 eclipse. This time, his home in Salem, South Carolina, is smack-dab in the path of totality, a 70-mile-wide stretch of land that will experience the fullest effects of the eclipse, like a sash of darkness draped across the country. Liebenberg will set up his instruments in his driveway and watch with his family. After all these years, he hasn’t tired of nature’s wondrous performance.
“The onset of the darkness provides a somewhat eerie feeling, and then the shadow sweeps over. It’s an awesome sight,” Liebenberg, 85, said. “I appreciate the fact that people have spent lives and time and effort to make calculations so that I am in the right place and here is, in fact, a total eclipse.”
In his early eclipse-chasing days, Liebenberg would go to the library and check out catalogs that listed upcoming eclipses; despite its rarity in any one place, a total solar eclipse is visible from somewhere on Earth every year and a half, and math-savvy people can predict them thousands of years into the future. His trips were often funded through laboratories or other scientific institutions, like Los Alamos Scientific Laboratory in New Mexico, where he worked for many years. Sometimes he had to pay his own way. Eclipse chasing, he said, has never been “what pays the bills.”
Some eclipses have been better than others. For Liebenberg and other eclipse watchers, clouds are the biggest enemy. In 2013, Liebenberg flew to Uganda to catch an eclipse that would produce just 20 seconds of totality. His viewing spot was moved at the last minute because the Ugandan president would be there, and his tour leader thought it best to avoid the crowds and security measures that would accompany the high-level visit. The original spot saw clear skies, while the new site greeted Liebenberg with a big cloud, blocking his view of the eclipse entirely.
The trick to dodging cloud cover is to fly. Liebenberg has witnessed several solar eclipses from inside a Boeing NC-135 plane as it wound its way through the narrow ribbon of the moon’s shadow—a complicated operation, particularly in the days before GPS. “You have to be overtaken by it and push yourself along the path,” Liebenberg said. “And it’s easy, at 500 miles per hour, to slip out of the bend of totality.” The pilots maneuvered to stay inside the path of totality as long as possible, allowing passengers to experience the darkness for longer than they could if they were watching from the ground below—and giving the term “eclipse chasing” a whole new meaning.
That’s how Liebenberg spent 74 minutes in totality in 1973—far longer than possible while on the ground, where totality usually lasts for only a few minutes. Liebenberg and other researchers observed a solar eclipse that year over Africa from the perch of a Concorde, a supersonic aircraft built jointly by the British and French. Liebenberg wore a fire-resistant U.S. Air Force flight suit. When the moon overtook the sun, turning the sky a deep purple, the Concorde was hurtling at Mach 2.08, riding the path of totality across the continent at more than twice the speed of sound.
To hear Liebenberg describe a particular visit, you’d think it happened weeks ago instead of decades. Some memories are more meaningful than others, like his flight on the Concorde, or his passage on a Navy ship south from Hawaii to Pukapuka in the Cook Islands, northeast of New Zealand. It was tradition for sailors to rough up passengers crossing the equator for the first time, and Liebenberg wasn’t spared. The young college student was blindfolded and his mouth doused with ketchup and mustard. He eventually received a certificate acknowledging this initiation, and he has it framed in his home office.
Smaller moments are just as vivid. Liebenberg remembers the warthog that stared him down on a dirt road in Zambia in 2001, and the coffee he drank at sunrise the next day. He remembers the French onion soup he had at breakfast in Toulouse—“to this day, the best I’ve ever had”—while he was trying to convince French engineers to let him fly on the Concorde. He recalls the snake he discovered in his room in Mazatlan, Mexico, in 1970, and that the wife of his host during a trip to Canada’s Northwest Territories in 1963 spelled her name as Memoree. His most recent eclipse—his 26th—occurred over Indonesian waters near the famous Komodo Island.
Liebenberg said he doesn’t consider himself a thrill-seeking eclipse chaser. He’s there for the science. When the darkness reaches his driveway, Liebenberg will take off his eclipse glasses and start taking measurements of the corona, the sun's scorching outer layer. Around him, life will start preparing for nighttime, unaware it’s not the real thing; birds will flutter toward their nests, plants will let their leaves droop. The temperature will sink a few degrees. Two minutes and 36 seconds later, daylight will begin its steady return.
“It all ends too quickly,” Liebenberg said.