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Advanced Camera For Surveys (ACS)

An optical camera aboard the Hubble Space Telescope that uses CCD detectors rather than photographic film to make images. The camera covers twice the area, has twice the sharpness, and is up to 10 times more efficient than the telescope’s Wide Field and Planetary Camera 2. The camera’s wavelength range spans from ultraviolet to near-infrared light. The camera’s sharp eye and broader viewing area allow astronomers to study the life cycles of galaxies in the remotest regions of the universe. Astronauts installed the camera aboard the telescope in March 2002.


Provide all the electrical power to support Hubble operations during the night portion of its orbit, when the telescope is in Earth’s shadow. The telescope’s orbit is approximately 97 minutes long. Roughly 61 minutes of Hubble’s orbit are in sunlight and 36 minutes are in Earth’s shadow. During Hubble’s sunlight or daytime period, the solar arrays provide power to the onboard electrical equipment. The solar arrays also charge the spacecraft’s batteries so they can power the spacecraft during the night portion of Hubble’s orbit. Hubble has six nickel-hydrogen batteries. The batteries that will be replaced have been onboard Hubble since the telescope was launched in April 1990.