Breast Cancer DetectionNASA's Jet Propulsion Laboratory has come up with a technique to decrease exposure to harmful x-rays in mammographies or breast radiography. Usually, physicians make more than one exposure to arrive at an x-ray film of acceptable density. Now the same solar cells used to convert sunlight into electricity on space satellites can make a single exposure sufficient. When solar cell sensor is positioned directly beneath x-ray film, it can determine exactly when film has received sufficient radiation and has been exposed to optimum density. At that point associated electronic equipment sends signal to cut off x-ray source. Reduction of mammography to single exposures not only reduced x-ray hazard significantly, but doubled the number of patient examinations handled by one machine. The NASA laboratory used this control system at the Huntington Memorial Hospital with overwhelming success.