NASA’s Mars Reconnaissance Orbiter (MRO) has detected large-scale movement of Martian sand dunes, according to a statement from the space agency. In fact, NASA believes that the movement of Martian sand dunes mirrors the movement of terrestrial sand dunes.
The large-scale movement of Martian sand dunes surprised scientists studying images from the MRO, because the Red Planet has a more tenuous atmosphere than Earth. In addition, Mars’ high-speed winds are more infrequent and anemic than Earth’s.
Images from MRO’s High Resolution Imaging Science Experiment (HiRISE) camera helped scientists confirm the large-scale movement of Martian sand dunes. Scientists have identified sand dunes as wide as 200 feet moving across Mars. Prior to the images being available, scientists thought that Martian sand dunes were inactive relics of past climate on the Red Planet.
“This exciting discovery will inform scientists trying to better understand the changing surface conditions of Mars on a more global scale,” said Doug McCuistion, the director of NASA’s Mars Exploration Program, in a statement. “This improved understanding of surface dynamics will provide vital information in planning future robotic and human Mars exploration missions.”
Using a new software tool at the California Institute of Technology, scientists examined before-and-after images of the Martian sand dunes. The software tool looked at the motions of sand ripples, unearthing that sand ripples move more quickly the higher up they are on a sand dune. Scientists were able to determine that entire sand dunes are moving on Mars by connecting the ripples’ movements to their spot on the dune. The software tool analyzed images of the Nili Patera sand dune field.
“We chose Nili Patera because we knew there was sand motion going on there, and we could quantify it,” said Nathan Bridges, a planetary scientist at Johns Hopkins University Applied Physics Laboratory and lead author of the Nature paper, in a statement. “The Nili dunes also are similar to dunes in places like Antarctica and to other locations on Mars.”
The MRO’s images also helped scientists understand more about how blowing sand could be actively eroding Martian rocks. Given new evidence, scientists believe that rocks in the Nili Patera sand dune field are being worn away at a similar pace as the rocks near sand dunes in Antarctica.
“Our new data shows wind activity is indeed a major agent of evolution of the landscape on Mars,” said Jean-Philippe Avouac, Caltech team leader, in a statement. “This is important because it tells us something about the current state of Mars and how the planet is working today, geologically.”
Scientists determined that more than two cubic yards of sand would pass within a one-yard width of someone if they stood in the same spot in the Nili Patera dunes for one Earth year.
“No one had estimates of this flux before,” said Mr. Bridges. “We had seen with HiRISE that there was dune motion, but it was an open question how much sand could be moving. Now, we can answer that.”
The MRO’s images will help scientists look deeper into other Martian mysteries, like when the heavy surface erosion of the Red Planet took place.
The study was published Wednesday in the journal Nature.