 Heike Kamerlingh Onnes

Heike Kamerlingh Onnes was a Dutch physicist known for his pioneering work in low-temperature physics. He was born on September 21, 1853, and passed away on February 21, 1926. Onnes is perhaps best known for his discovery of superconductivity in 1911, when he observed that the electrical resistance of mercury disappeared completely when it was cooled below a certain critical temperature (approximately 4.2 K, or -268.95 °C).