Marc William Buie (/ˈbuːi/; born September 17, 1958) is an American astronomer and prolific discoverer of minor planets who works at the Southwest Research Institute in Boulder, Colorado in the Space Science Department.

[1] Formerly he worked at the Lowell Observatory in Flagstaff, Arizona, and was the Sentinel Space Telescope Mission Scientist for the B612 Foundation, which is dedicated to protecting Earth from asteroid impact events.

[6] In the lead up to the fly-by, Buie also led a successful occultation campaign in Argentina and South Africa to observe Arrokoth as it passed in front of a distant star to refine the estimates of its size, shape, and orbit.

Jim Green, NASA's director of planetary science at the time, called the effort "the most historic occultation on the face of the Earth.

He is also active in the development of state-of-the-art astronomical instrumentation having just completed the construction of an infrared imaging spectrograph, Mimir, in collaboration with Dan Clemens of Boston University.