![]() On October 3, 2007, HiRISE was turned toward Earth, and took a picture of it and the Moon. Further work showed that the degradation can be reversed by heating the ADCs. 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. As of March, the degradation appeared to have stabilized, but the underlying cause remained unknown. The problems seemed to disappear when higher temperatures were used to take pictures with the camera. In February 2007 seven detectors showed signs of degradation, with one IR channel almost completely degraded, and one other showing advanced signs of degradation. On OctoHiRISE took the first image of Victoria Crater, a site which was also under study by the Opportunity rover. It was turned on successfully on September 27, and took its first high-resolution pictures of Mars on September 29. 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. On March 10, 2006, MRO achieved Martian orbit and primed HiRISE to acquire some initial images of Mars. These images helped to calibrate the camera and prepare it for taking pictures of Mars. There are at present no firm plans for a replacement, though NASA is seriously considering the possibility of building and launching an even more advanced orbiter to Mars as early as 2022.During the cruise phase of MRO, HiRISE took multiple test shots including several of the Moon and the Jewel Box cluster. We may only be an errant cosmic ray, solar flare or micrometeorite strike away from hardware failures that draw the curtain down on MRO’s revolutionary observations. MRO, originally intended for a primary mission lasting only about two years, is now well past its designed lifetime, and its systems and instruments are showing their age with degraded performance and more frequent glitches. To celebrate MRO’s tenth anniversary, we have gathered some of the spacecraft’s best images as suggested by several of the mission’s leading scientists. All that data could also intimately shape Mars’s future, as NASA uses it to find landing sites for human outposts and long-term habitation. Other instruments on MRO, such as its Compact Reconnaissance Imaging Spectrometer (CRISM), have managed to map more than 95 percent of Mars at lower resolutions, providing their own new perspective on the planet’s past and present. The sharpness of HiRISE’s vision comes at a price-a narrow field-of-view that has limited its coverage to less than 2.5 percent of the planet’s surface during MRO’s decade in orbit. Whirling dust devils meander across the sun-warmed equator, and in the colder mid-latitudes water vapor wafts from once-buried ice exposed in fresh impact craters. HiRISE’s Mars is a world of tumbling landslides, creeping glaciers and marching sand dunes. Seen through HiRISE’s optics, which can reveal surface features as small as a desk, Mars suddenly becomes a different place, a livelier planet that, though still relatively inert on large scales, teems with activity on smaller ones. A disproportionate amount of that data comes from a single instrument onboard, the High Resolution Imaging Science Experiment (HiRISE), a camera fed by a 0.5-meter telescope. Ever since it slipped into orbit, it has beamed back some 264 terabits of data, more than all of humanity’s other interplanetary probes combined. But after that short spate of activity the planet had apparently lapsed into senescence, becoming little more than an inert, rusty rock.Īcross a decade and about 45,000 orbits, MRO’s advanced cameras, spectrographs and radar have helped researchers chart the history of Mars’s shift from warm and wet to cold and dry, but more importantly the information has revealed a world more dynamic and decidedly less drab than previously appreciated. Ancient river valleys and flow channels first seen by orbiters in the 1970s told scientists Mars had briefly been a warm, wet world nearly four billion years ago. Yesterday marked the tenth anniversary of NASA’s Mars Reconnaissance Orbiter’s (MRO) arrival into Martian orbit, on a mission that would revolutionize our views of the planet.
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