Superconductivity, discovered in 1911 by Kamerlingh Onnes, is the phenomenon where a material’s electrical resistance drops to zero at cryogenic temperatures. The temperature at which this occurs is called the transition temperature and varies by material. In this experiment, the transition temperature of a high-temperature superconductor, BSCCO (Bismuth), is measured. The sample is cooled with liquid nitrogen in a probe chamber equipped with a thermocouple. A four-point method is used to measure resistivity—outer points for current and inner points for voltage. A temperature sensor on the sample tracks temperature, and the voltage drop is recorded to determine the transition temperature.