In 1911, physicist Heike Kamerlingh Onnes aimed to lower mercury’s temperature to as close to absolute zero as possible. He hoped to win a disagreement with Lord Kelvin, who thought metals would stop conducting electricity altogether at extremely low temperatures. Carefully manipulating a set of glass tubes, Kamerlingh Onnes and his team lowered the mercury’s temperature to 3 K (-454 F). Suddenly, the mercury conducted electricity with zero resistance. Kamerlingh Onnes had just discovered superconductivity.