posted 06-02-2025 06:25 PM               

He announced his diagnosis and his impending passing on April 15th on social media and on the Solar Eclipse Message List (SEML) forum as he prepared to enter hospice care, sparking an outpouring of sorrow, sympathy, good wishes, and thank-you's for his life's work.

Fred's fascination with the lunar shadow began with an off-the-track partial eclipse in 1963 and was cemented several years later by the total solar eclipse that traveled along the U.S. Eastern Seaboard in 1970. Upon his death 55 years later, he had witnessed 52 solar eclipses of various types, of which 31 were total. He had also helped countless others prepare for and experience the wonder of totality, thanks to his dedication to outreach. ...

As a NASA scientist at the Goddard Space Flight Center, Fred's research focused largely on planetary atmospheres using an infrared spectrometer that he and his colleagues took first to Kitt Peak and then to NASA's Infrared Telescope Facility on Mauna Kea, Hawai'i. He coauthored papers on winds on Titan, ethane in Jupiter's atmosphere, ozone on Mars, and hydrocarbons in the outer planets.

But to most of us, he is best known for his calculations of the circumstances of solar and lunar eclipses and the many publications and platforms he used to spread that information globally to scientists, eclipse chasers, and the public. Prior to 1994, the U.S. Naval Observatory issued eclipse circulars; when their funding ended, Fred wrote to me and proposed that we take on the job, under NASA's auspices. The result was 13 circulars from 1994 to 2010 and a popular NASA website that he developed and maintained. When NASA funding ended with his retirement in 2009, he took to the web and to private publishing to continue the work. In recognition of his efforts, asteroid 14120 was named Espenak in 2003. To the public, he became "Mr. Eclipse."