At the heart of the new Vera C. Rubin Observatory in Chile is the world’s largest digital camera. About the size of a small car, it will create an unparalleled map of the night sky.The observatory’s first public images of the sky are expected to be released on June 23. Here’s how its camera works.When Times reporters visited the observatory on top of an 8,800-foot-high mountain in May, the telescope was undergoing calibration to measure minute differences in the sensitivity of the camera’s pixel...