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''For the Apple accessory see Twelve South'' High Resolution Imaging Science Experiment is a camera on board the Mars Reconnaissance Orbiter. The 65 kg (143 lb), $40 million USD instrument was built under the direction of the University of Arizona's Lunar and Planetary Laboratory by Ball Aerospace & Technologies Corp. It consists of a 0.5 m (19.7 in) aperture reflecting telescope, the largest so far of any deep space mission, which allows it to take pictures of Mars with resolutions of 0.3 m/pixel (about 1 foot), resolving objects below a meter across. HiRISE has imaged Mars landers on the surface, including the ongoing Curiosity〔(HiRISE Operations Center - Images of Curiosity rover (September 29, 2002) )〕 and Opportunity rover missions.〔(VOA News - Mars Orbiter Photographs Old NASA Lander (February 9, 2012) )〕 ==History== In the late 1980s, Alan Delamere of Ball Aerospace began planning the kind of high-resolution imaging needed to support sample return and surface exploration of Mars. In early 2001 he teamed up with Alfred McEwen of the University of Arizona to propose such a camera for the Mars Reconnaissance Orbiter (MRO), and NASA formally accepted it November 9, 2001. Ball Aerospace was given the responsibility to build the camera and they delivered HiRISE to NASA on December 6, 2004 for integration with the rest of the spacecraft. It was prepared for launch on board the MRO on August 12, 2005, to the cheers of the HiRISE team who were present. During the cruise phase of MRO, HiRISE took multiple test shots including several of the Moon and the Jewel Box cluster. These images helped to calibrate the camera and prepare it for taking pictures of Mars. On March 10, 2006, MRO achieved Martian orbit and primed HiRISE to acquire some initial images of Mars. The instrument had two opportunities to take pictures of Mars (the first was on March 24, 2006) before MRO entered aerobraking, during which time the camera was turned off for six months. It was turned on successfully September 27, and took its first high-resolution pictures of Mars on September 29. On October 6, 2006 HiRISE took the first image of Victoria Crater, a site which is also under study by the Opportunity rover.〔(HiRISE | Victoria Crater at Meridiani Planum (TRA_000873_1780) )〕 In February 2007 seven detectors showed signs of degradation, with one IR channel almost completely degraded, and one other showing advanced signs of degradation. The problems seem to disappear when higher temperatures are used to take pictures with the camera. As of March, the degradation appeared to have stabilized, but the underlying cause remained unknown. Subsequent experiments with the Engineering Model (EM) at Ball Aerospace provided definitive evidence for the cause: contamination in the analog-to-digital converters (ADCs) which results in flipping bits to create the apparent noise or bad data in the images, combined with design flaws leading to delivery of poor analog waveforms to the ADCs. Further work showed that the degradation can be reversed by heating the ADCs. On 2007-10-03, HiRISE was turned toward Earth, and took a picture of it and the Moon. In a full-resolution color image, Earth was 90 pixels across and the Moon was 24 pixels across from a distance of 142 million km. On May 25, 2008, HiRISE imaged NASA's Mars Phoenix Lander parachuting down to Mars. It was the first time that one spacecraft imaged the final descent of another spacecraft onto a planetary body.〔(【引用サイトリンク】 title=Camera on Mars Orbiter Snaps Phoenix During Landing )〕 On April 1, 2010, NASA released the first images under the HiWish program in which the public suggested places for HiRISE to photograph. One of the eight locations was Aureum Chaos.〔http://uahirise.org/releases/hiwish-captions.php〕 The first image below gives a wide view of the area. The next two images are from the HiRISE image.〔http://hirise.lpl.arizona.edu/ESP_016869_1775〕 By 2010, HiRISE had imaged about one percent of Mars's surface.〔(Microsoft and NASA Bring Mars Down to Earth Through the WorldWide Telescope (07.12.10) - NASA )〕 It was designed to capture smaller areas at high resolutionother instruments scan much more area to find things like fresh impact craters. Image:Aureum Chaos wide context.JPG|THEMIS image of wide view of following HiRISE images. Black box shows approximate location of HiRISE images. This image is just a part of the vast area known as Aureum Chaos. Click on image to see more details. Image:Aureum Chaos wide view.JPG|Aureum Chaos, as seen by HiRISE, under the HiWish program. Image is located in Margaritifer Sinus quadrangle. Image:Aureum Chaos HiWish.JPG|Close up view of previous image, as seen by HiRISE under HiWish program. Small round dots are boulders. Image:Lobate feature with hiwish.JPG|Probable glacier as seen by HiRISE under HiWish program. Radar studies have found that it is made up of almost completely pure ice. It appears to be moving from the high ground (a mesa) on the right. Location is Ismenius Lacus quadrangle. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「HiRISE」の詳細全文を読む スポンサード リンク
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