Payload Specialist(Detroit)
Jarvis, 41, was a Hughes Aircraft Co. engineer who was flying on Challenger to test the effects of weightlessness on fluid in tanks. He had been selected as a payload specialist in 1984.
It was hoped his experiments would give engineers new information on the design of liquid-fueled rockets.
Jarvis graduated from high school in Mohawk, N.Y. He earned a bachelor's degree in electrical engineering from the State University of New York in Buffalo and a master's in electrical engineering from Northeastern University in Boston.
He served as a satellite engineer in the Air Force and achieved the rank of captain before resigning to become a Hughes engineer.
Jarvis and his wife, Marcia, lived in Hermosa Beach, Calif.