Samuel Thornton Durrance (September 17, 1943 – May 5, 2023) was an American scientist who flew aboard two NASA Space Shuttle missions as a payload specialist.

[4] Durrance was a principal research scientist in the Department of Physics and Astronomy at Johns Hopkins University, Baltimore, Maryland.

[1] Durrance had been involved in the flight hardware development, optical and mechanical design, construction, and integration of the Hopkins Ultraviolet Telescope and the Astro Observatory,[8] and had conducted research and directed graduate students at the Johns Hopkins University[9] He had designed and built spectrometers, detectors, and imaging systems, and made numerous spacecraft and ground-based astronomical observations.

He conceived and directed a program at Johns Hopkins University to develop adaptive-optics instrumentation for ground-based astronomy.

He died at a hospice facility in Viera, Florida, on May 5, 2023, of complications from a fall, after battling dementia and Parkinson's disease.