linear ramp filters divided into three individual segments each provide continuous imaging capability from 380 nm to 1070 nm and so ensure adequate sampling of emission lines over a large range in redshift. Only the middle segment is accessible to the HRC. The SBC wheel is populated with one medium-band filter (Lyα), five long-pass filters, and two objective prisms. Timeline March 7, 2002, ACS installed in the Hubble Space Telescope (STS-109) June 19, 2006; ACS/WFC and HRC go offline due to problem with Low Voltage Power Supply July 4, 2006 ACS resumed science operations by switching to back-up electronics 23 September 23, 2006, the ACS goes offline again October 9, 2006 ACS problem diagnosed and resolved. January 27, 2007 the ACS failed due to a short circuit in its backup power supply. 2009, ACS/WFC repaired (STS-125) See also Cosmic Origins Spectrograph Faint Object Camera Faint Object Spectrograph Goddard High Resolution Spectrograph Near Infrared Camera and Multi-Object Spectrometer Space Telescope Imaging Spectrograph Wide Field and Planetary Camera Wide Field and Planetary Camera 2 Wide Field Camera 3 References External links the ACS Web site at Johns Hopkins University, which includes a complete description of the instrument, the ground calibration campaigns, the detectors, and the filters. the ACS Web site at the Space Telescope Science Institute (STScI) All Publicly released ACS images a collection of HST images, including ACS, at the Gallery of the Hubble Site ACS at ESA/Hubble Hubble Space Telescope instruments Space imagers