Jay Pasachoff, who followed solar eclipses worldwide, dies at 79

Jay M. Pasachoff, a Williams College astronomer who has spent more than 50 years traveling the world to watch solar eclipses and, with 74 sightings, has likely seen more of them than anyone in history, died Sunday at his home in Williamstown, Mass. He was 79.

The cause was lung cancer, said his wife Naomi Pasachoff.

for dr Pasachoff was so overwhelmed by the sublime grandeur of a total solar eclipse that it defied easy description and its appeal needed no explanation: if you didn’t understand it, he said, you obviously hadn’t seen one. Thousands of people knew what he meant. Hordes of them travel thousands of miles to spend a few minutes in the middle of the day in an artificial night.

“We are umbraphiles,” he wrote in the New York Times in 2010. “Having once stood in the umbra of the moon during an eclipse, we are propelled again and again as the moon moves between the earth and the sun.”

But he was more than just an Eclipse fan. He studied the corona, the outermost layer of the Sun’s atmosphere, which, being a millionth as bright as the Sun itself, is best studied when the rest of the Sun is occluded by the Moon – in other words, during a solar eclipse.

The corona may fade in the sun’s light, but it’s a million degrees hotter, a mystery Dr. Pasachoff fascinated. He liked to say that the mystery had indeed been solved, but that there were 17 possible solutions, and a focus of his work was testing those theories.

dr Pasachoff, with good reason, preferred to be referred to as an “eclipse precursor” rather than a “eclipse pursuer.” He would spend up to three years before an eclipse preparing equipment, arranging grants, arranging travel, and planning all of the myriad contingencies that might interfere with the few minutes he and his team would have to see how the moon passes in front of the sun.

Knowing the path of a solar eclipse across the surface of the earth was not enough for starters. dr Pasachoff studied weather almanacs to find out where it was least likely to be obscured by an unusual storm or morning fog. Sometimes that meant trekking into the deserts of northern Kenya or flying 41,000 feet over Antarctica, as he did on December 4, 2021 on one of his most recent expeditions.

Although Williams College does not have a graduate program in astronomy, Dr. Pasachoff worked so closely with his students that over time he built up a vast network of contacts around the world, making him one of the best-connected scientists ever.

“He knew people everywhere,” Michael J. Person, director of MIT’s Wallace Astrophysical Observatory, said in an interview. “I knew I could call Jay Pasachoff and say, ‘I need a telescope in New Guinea,’ and he would know someone there.”

To the untrained eye, one solar eclipse may appear to be more or less the same as the other. But dr Pasachoff knew otherwise. To him the sun was less a stable object than a flux in its perpetual transformation, and he said he never saw the same eclipse twice.

“Everyone is different,” he said in a 2021 interview for this obituary. “The sun is different. His outbursts are different. The structures on its surface are different.”

Jay Myron Pasachoff was born on July 1, 1943 in Manhattan. His father, Samuel, was a surgeon who left Jay shortly after birth to serve in the Army Medical Corps; During World War II he landed in Normandy and took part in the Battle of the Bulge. His mother, Anne (Traub) Pasachoff, was a teacher.

After his father returned from the war, the family moved from Manhattan to the Bronx, where Jay attended Bronx High School of Science. His interest in astronomy began early with visits to the Hayden Planetarium at the American Museum of Natural History; When he was in high school, he built telescopes with the Amateur Astronomers Association of New York.

At 16 he entered Harvard University. For his freshman seminar, he chose an astronomy class from Donald H. Menzel, an expert on solar eclipses. A total solar eclipse happened to begin off the coast of Massachusetts near Marblehead just a few weeks into the semester. dr Menzel borrowed a DC-3 plane from Northeast Airlines and took his class along with Polaroid’s CEO to watch.

It was Mr. Pasachoff’s first total solar eclipse and he was thrilled. He actually wanted to study mathematics, but ended up in astronomy instead. He received his bachelor’s degree in 1963, his master’s degree in 1965 and his Ph.D. 1969, all from Harvard.

After several years as a postdoctoral fellow at the California Institute of Technology, he came to Williams College in 1972 as the sole member of the astronomy department and director of the observatory, the oldest of its kind in the United States.

He married Naomi Schwartz in 1974. Along with her he is survived by his daughters Eloise and Deborah; his sister Nancy Kutner; and five grandchildren.

While making many contributions to astronomy, Dr. Pasachoff was also, if not better known, in his own words, the convert: he spoke to the news media, wrote for general scholarly publications, and encouraged amateurs to share his passion for the night sky.

His expeditions often included not only other scientists, but also undergraduate students, graduate students from other schools, and a clique of friends and family members, all eager to hear from Dr. to learn Pasachoff.

“He had this rare quality of seeing all of his students where they wanted to be and then doing whatever he could to help them get there,” said Amy Steele, a postgraduate student in astronomy at McGill University working with Dr Pasachoff in Williams and went with him on three expeditions.

He is the author of several school and college textbooks, an updated edition of Peterson’s Field Guide to the Stars and Planets (1999), and co-authored with art historian Roberta JM Olson, Cosmos: The Art and Science of the Universe (2019). ).

dr Pasachoff loved astronomy, and astronomy loved him back: He and his wife are immortalized in the names of two asteroids, 5100 Pasachoff and 68109 Naomipasachoff.