1948-1951: Hastings began his graduate studies at Princeton University (Princeton, NJ) in 1948 in the laboratory of E. Newton Harvey, the world leader of luminescence studies at the time, and focused on the role of oxygen in the luminescence of bacteria, fireflies, ostracod crustaceans and fungi.
1951-1953: He then joined the lab of William D. McElroy, another student of Harvey's, at Johns Hopkins University (Baltimore, MD) where he discovered both the stimulatory effects of coenzyme A and gating control by oxygen of firefly luminescence, and that flavin is a substrate in bacterial luminescence.