Jay Pasachoff, globetrotting solar eclipse expert, dies at age 79

The solar astronomer would sometimes spend years preparing for the Moon to briefly block out the Sun’s disk.
By | Published: November 21, 2022 | Last updated on May 18, 2023
Solar astronomer Jay Pasachoff poses during an eclipse he observed at the Jansky Very Large Array.
Jay Pasachoff (Williams College)

Jay Pasachoff, a solar astronomer who witnessed 74 solar eclipses over the course of his life, died at his home in Williamstown, Massachusetts, on Sunday, Nov. 20. He was 79 years old.

Pasachoff was Field Memorial Professor of Astronomy and Director of the Hopkins Observatory at Williams College. He was not only known for his expert knowledge of eclipses, but also for his valuable weather predictions. By combing through available data such as weather almanacs, Pasachoff had an impressive track record for identifying the best eclipse viewing sites based on how likely they were to host clear skies during totality.

“Jay Pasachoff was a towering figure in the astronomical community. Besides his scientific achievements, Jay was an exemplar in promoting citizen science and selfless with his time,” Michael Zeiler, a maker of eclipse maps, tells Astronomy. “What I will miss most about Jay is his humanity and infectious enthusiasm about sharing the splendor of total solar eclipses.”

An early start in astronomy

Born July 1, 1943, in Manhattan, Pasachoff’s mother was a teacher, while his father was a surgeon who later served in the Army Medical Corps during World War II.

Pasachoff’s interest in astronomy developed at a young age. After moving to the Bronx, Pasachoff would take trips to the Hayden Planetarium. And as a high schooler, he would begin tinkering with building telescopes.

Then, as a freshman at Harvard (at age 16), Pasachoff took an astronomy course taught by solar eclipse expert Donald Menzel. Pasachoff witnessed his first total solar eclipse just a few weeks later, when Menzel secured access to a plane to let his student’s experience totality from the sky.

Within a decade, Pasachoff earned his bachelor’s, master’s, and Ph.D. in astronomy from Harvard. And over the next 50 years, he made every effort to ensure he could view more than 70 solar eclipses.

A half-century of eclipses

Fred Espenak, EclipseWise.com (May 2022)

“We are umbraphiles,” Pasachoff wrote in a 2010 Op-Ed in the New York Times. “Having once stood in the umbra, the moon’s shadow, during a solar eclipse, we are driven to do so again and again, whenever the moon moves between the Earth and the sun.”

Pasachoff was not only a lover of eclipses. He was a talented academic who studied the Sun’s tenuous, outermost layer: the corona. Despite the corona being surprisingly hot, the brightness of the Sun’s disk overwhelms it, making it difficult to study. But solar eclipses, when the Moon perfectly obscures the Sun, offer a great opportunity to study the solar corona without the need for expensive satellite observations.

Pasachoff, however, was perhaps best known for his valiant public outreach efforts, encouraging people of all skill levels to seek out the wonderous celestial sights the sky has to offer. He understood that the awesome sights and mysteries Mother Nature has to offer can inspire the next generation of scientific thinkers.

“I think if we get millions or tens of millions of schoolchildren out watching the eclipse — it is so amazing to be out during totality, and it’s such a dazzling spectacle, that maybe they could be persuaded to pay more attention to their studies,” Pasachoff said during a 2017 interview with Quanta Magazine about the Great American Eclipse, “Who knows, in the long term we may get more scientists out of this, more big discoveries.

“Jay Pasachoff was a great man, an academic leader, a distinguished professor, and a spectacular eclipse chaser. It was my privilege to call him my friend. In addition to his scholarly pursuits, he was an early supporter of and contributor to Astronomy magazine, and we will always treasure our relationship with Jay,” says David J. Eicher, Editor-in-Chief of Astronomy magazine. “The astronomy world has lost a leading light, and we are all happy that at least we could know this wonderful man as long as we did.”