Stuhlinger played a small but important role in the race to launch a US satellite after the success of Sputnik 1. There was little time to develop and test automated guidance or staging systems, so Stuhlinger developed a simple spring-powered staging timer that was triggered from the ground. On the night of January 31, 1958, Stuhlinger was at the controls of the timer when the Explorer 1 was launched, triggering the device right on time. He became known as "the man with the golden finger." This satellite discovered the Van Allen radiation belt through a cosmic ray sensor, a felicitous intersection with his early physics expertise, included in a science package supervised by Stuhlinger.