Dr. Allen's son Joel Hynek directed the design of the camouflage for the creature in the movie Predator (1987).
He was the astronomy consultant to the US Air Force's Project Sign, which was established in 1948 to investigate sightings of UFOs.
He received a bachelor's degree from the University of Chicago. He did research for his doctoral degree at Yerkes Observatory in Wisconsin. He then was hired as an instructor at Ohio State University, and became a professor.
His father was a cigar-maker, and his mother taught grammar school.
He was a director of the Operation Moonwatch satellite tracking program, secretary of the American Astronomical Society, and was influential in the Project Star Gazer balloon program.