So, scientists and engineers must slowly adjust the temperature for each piece until the optimum is reached. All the while, technicians are testing each computer and each scientific instrument to make sure they're functioning properly. These tests are time-consuming and take weeks to complete. The temperature must operate at cold temperatures for the CCDs to operate effectively. Each of the camera's detectors contain 640,000 pixels.
Pixels swallow light from a target, such as a star or a galaxy.
The amount of light each pixel collects is translated into a number. It's almost like putting together pieces of light and dark tile to make a mosaic. The detectors replace film because they are more sensitive to light. Taking images of dim objects is important for astronomers looking for faint, faraway stars and galaxies. Film also is impractical for a telescope orbiting in space.