Leslie Peltier was a US amateur astronomer, who lived and pursued his hobby in the early and middle 20th century.
He is noted for his interest in variable stars. In eight decades of observing he submitted over 132,000 observations of variables to the American Association of Variable Star Observers (AAVSO). Peltier also discovered twelve comets and six novae. In addition to astronomy, he was also interested in biology and geology.
Peltier is principally known for his autobiography Starlight Nights, for which he was named Ohio Author of the Year in 1966. This work has been read by generations of astronomers.
The renowned astronomer Harlow Shapely once referred to Leslie C. Peltier as "the world's greatest living amateur astronomer."
After his death the Astronomical League created an annual "Leslie C. Peltier Award" for outstanding contributions to astronomy, in honour of his memory.