Michael Francis A'Hearn (November 17, 1940 – May 29, 2017) was an American astronomer and astronomy professor at the University of Maryland College of Computer, Mathematical, and Natural Sciences.

He aided in the development of systems for surveying abundances in comets as well as techniques for determining the sizes of cometary nuclei which uses optical and infrared measurements.

His studies focused on comets as well as asteroids and he also supervises numerous graduate students.

He authored over 100 papers published in journals and was also an avid sailor who had a commercial coast guard license.

[2] In June 1986, the main-belt asteroid 3192 A'Hearn, discovered by American astronomer Edward Bowell at Lowell's Anderson Mesa Station in Flagstaff, Arizona, was named after him in honor of his contributions to cometary science.