|Image credit: University of Arizona, NASA, JPL.|
Researchers at the University of Arizona have used NASA’s High Resolution Imaging Experience (HiRISE) camera to capture images of the Valles Marineris canyon on Mars. Researchers want to study the canyon, which is 2,500 mi (4,000 km) long and has depths up to 4 mi (7 km), to better understand how it formed and what its formation means for the history of Mars itself. Valles Marineris is the largest known canyon in the solar system and it may hold the key to solving numerous Martian mysteries.
The HiRISE camera on the Mars Reconnaissance Orbiter weighs roughly 143 lbs. (65kg). It is 5.2′ (1.6 m) long and has a diameter of about 2.9′ (0.9 m). Per NASA, the highly specialized camera ‘can acquire images containing up to 28 Gb of data in as little as 6 seconds.’ In terms of resolution, NASA says, ‘From an altitude that varies from 200 to 400 kilometers (about 125 to 250 miles) above Mars, HiRISE acquires surface images containing individual, basketball-size (30 to 60 centimeters, or 1 to 2 feet wide) pixel elements, allowing surface features 4 to 8 feet across to be resolved.’
|NASA’s HiRISE camera|
The camera’s focal length is about 40′ (12 m) and it has an F24 aperture. HiRISE operates in visible wavelengths but can also make observations in additional wavelengths using different filters. There are 14 CCD sensors in HiRISE, which 2,048 x 128 pixels each. HiRISE’s onboard computer reads lines from the sensors in time with the orbiter’s speed relative to Mars’ surface. Image size is theoretically unlimited but limited in real-world terms by the 28 Gb capacity of the computer. The maximum practical size of images captured by HiRISE depends upon the color of the image. Red color images can be up to 2520MP and blue-green and near-infrared images max out at 504MP.
HiRISE has been onboard the orbiter since 2006 and the HiRISE project cost roughly $40M. The camera was built under the direction of the Lunar and Planetary Laboratory at the University of Arizona.
Observations like the recent ones by the University of Arizona, NASA and JPL shed considerable light on the mysteries of Valles Marineris. According to Popular Science, ‘images like those recently released by the researchers at the University of Arizona have also suggested that landslides and ancient rivers sculpted Valles Marineris after it ripped open. Getting better looks at small details, like fault lines and areas where rocky materials clump together, helps scientists fine-tune their ideas of how Valles Marineris came to be.’
The Obliquity of Mars (Periodic Bedding in Tithonium Chasma). This image, recently captured by HiRISE and researchers at the University of Arizona, shows the Tithonium Chasma feature of the Valles Marineris canyon on Mars.
The University of Arizona writes, ‘This HiRISE image of an east-facing slope in Tithonium Chasma was taken to follow up an earlier Context Camera image that seemed to show sediment layers of near-uniform thickness. These sediment layers are the dark and light stripes that run diagonally across the center of the observation. In this top-down view, afternoon sunlight picks out subtle east-west trending ridges in the east-facing slope. The dark and light stripes appear to deflect to the east (downslope) across the ridges. To a geologist, this outcrop pattern shows that the dip of the ancient sediment layers is gentler than the slope of the modern hillside. Further analysis of the image may determine whether these layers do record ancient obliquity-driven climate change on Mars.’ For more information, click here.
Using HiRISE, researchers are able to closely investigate different regions of the canyon, including the Tithonium Chasma seen in the image above. With the resolving power of HiRISE, diagonal slashes are visible on the Martian surface, which the researchers believe are indicative of ‘ancient cycles of freezing and thawing’ on Mars. The images also show evidence of ancient landslides and even ancient rivers that helped shape the impressive canyon.
Aided by the technology in NASA’s HiRISE camera, researchers have been able to observe the small details required to further our collective understanding of Mars and its development over the previous millions and even billions of years. You can learn more about HiRISE and its team by clicking here.
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