Chien-Shiung Wu, a physicist at Columbia University, designs the decisive experiment to test Lee and Yang's theoretical prediction (1956) that the weak interaction might not conserve parity. Lacking the necessary cryogenic facilities at Columbia, she turns to a team at the National Bureau of Standards (NBS) in Washington D.C. composed of Ernest Ambler, Raymond W. Hayward, Dale D. Hoppes, and Ralph P. Hudson, experts in cryogenics and radiation detection. Together they cool cobalt-60 nuclei to temperatures near absolute zero (about 0.003 K) and align them with a magnetic field, so that their spin is oriented in a known direction. If parity were conserved, the electrons emitted in beta decay should be distributed symmetrically relative to the spin axis. On December 27, 1956, the team observes for the first time a clear asymmetry: more electrons are emitted in the direction opposite to the nuclear spin than in the same direction. The result, received by Physical Review in January 1957 and published in February, directly and "visibly" demonstrates that nature distinguishes between left and right in the weak interaction, ruling out one of the most deeply entrenched symmetries of 20th-century physics. The finding arrives the same week as the independent confirmations by Garwin-Lederman-Weinrich and Friedman-Telegdi on the π-μ-e system, and precipitates the 1957 Nobel Prize in Physics for Lee and Yang — Wu, despite having led and designed the decisive confirming experiment, was not included in that prize.