HiRISE

HiRISE incorporates a 0.5-meter primary mirror, the largest optical telescope ever sent beyond Earth's orbit. The mass of the instrument is 64.2 kg.[http://cat.inist.fr/?aModele=afficheN&cpsidt=20649610 Mission to Mars: the HiRISE camera on-board MRO], ''Focal plane arrays for space telescopes III,'' 27–28 August 2007, San Diego, California, USA

HiRISE incorporates a 0.5-meter primary mirror, the largest optical telescope ever sent beyond Earth's orbit. The mass of the instrument is 64.2 kg.[http://cat.inist.fr/?aModele=afficheN&cpsidt=20649610 Mission to Mars: the HiRISE camera on-board MRO], ''Focal plane arrays for space telescopes III,'' 27–28 August 2007, San Diego, California, USA

Red color images are at 20,048 [[pixel]]s wide (6 km in a 300 km orbit), and blue-green and NIR are at 4,048 pixels wide (1.2 km). These are gathered by 14 CCD sensors, {{nowrap|2048 × 128 pixels}}. HiRISE's onboard computer reads out these lines in time with the orbiter's [[ground speed]], meaning the images are potentially unlimited in height. Practically this is limited by the onboard computer's {{nowrap|28 [[Gigabit|Gbit]]}} ({{nowrap|3.5 GB}}) memory capacity. The nominal maximum size of red images (compressed to 8 bits per pixel) is about 20,000 × 126,000 pixels, or 2520 [[megapixel]]s and 4,000 × 126,000 pixels (504 megapixels) for the narrower images of the B–G and NIR bands. A single uncompressed image uses up to 28{{nbsp}}Gbit. However, these images are transmitted compressed, with a typical maximum size of 11.2 gigabits. These images are released to the general public on the HiRISE website via a new format called [[JPEG 2000]].{{cite web |url=http://marsoweb.nas.nasa.gov/HiRISE/papers/6th_int_mars_conf/Delamere_HiRISE_InstDev.pdf |title=HiRISE: Instrument Development |work=NASA Ames Research Center website |access-date=7 February 2006 }}{{cite web |url=http://www.nasm.si.edu/research/ceps/cepsicons/highlights/fact_sheet_front.pdf |title=Fact Sheet: HiRISE |work=National Air and Space Museum |access-date=18 February 2006 |archive-url=https://web.archive.org/web/20130621134946/http://airandspace.si.edu/research/ceps/cepsicons/highlights/fact_sheet_front.pdf |archive-date=21 June 2013 }}

Red color images are at 20,048 [[pixel]]s wide (6 km in a 300 km orbit), and blue-green and NIR are at 4,048 pixels wide (1.2 km). These are gathered by 14 CCD sensors, {{nowrap|2048 × 128 pixels}}. HiRISE's onboard computer reads out these lines in time with the orbiter's [[ground speed]], meaning the images are potentially unlimited in height. Practically this is limited by the onboard computer's {{nowrap|28 [[Gigabit|Gbit]]}} ({{nowrap|3.5 GB}}) memory capacity. The nominal maximum size of red images (compressed to 8 bits per pixel) is about 20,000 × 126,000 pixels, or 2520 [[megapixel]]s and 4,000 × 126,000 pixels (504 megapixels) for the narrower images of the B–G and NIR bands. A single uncompressed image uses up to 28{{nbsp}}Gbit. However, these images are transmitted compressed, with a typical maximum size of 11.2 gigabits. These images are released to the general public on the HiRISE website as [[JPEG 2000]].{{cite web |url=http://marsoweb.nas.nasa.gov/HiRISE/papers/6th_int_mars_conf/Delamere_HiRISE_InstDev.pdf |title=HiRISE: Instrument Development |work=NASA Ames Research Center website |access-date=7 February 2006 }}{{cite web |url=http://www.nasm.si.edu/research/ceps/cepsicons/highlights/fact_sheet_front.pdf |title=Fact Sheet: HiRISE |work=National Air and Space Museum |access-date=18 February 2006 |archive-url=https://web.archive.org/web/20130621134946/http://airandspace.si.edu/research/ceps/cepsicons/highlights/fact_sheet_front.pdf |archive-date=21 June 2013 }}

To facilitate the mapping of potential landing sites, HiRISE can produce stereo pairs of images from which the topography can be measured to an accuracy of 0.25 meter.

To facilitate the mapping of potential landing sites, HiRISE can produce stereo pairs of images from which the topography can be measured to an accuracy of 0.25 meter.