Physician Bernard A. Harris, Jr was born in Temple, Texas.

After completing his residency training in 1985 at the Mayo Clinic, Dr. Harris then completed a National Research Council Fellowship at NASA Ames Research Center, Moffett Field, California. While at Ames he conducted research in the field of musculoskeletal physiology, and disuse osteoporosis, completing his fellowship in 1987. He then joined NASA Johnson Space Center as a clinical scientist and flight surgeon.

Selected by NASA in January 1990, Dr. Harris became an astronaut in July 1991. He served as the crew representative for Shuttle Software in the Astronaut Office Operations Development Branch. A veteran of two space flights, Dr. Harris has logged more than 438 hours in space.