Recently, researchers have discovered for the first time the large wave migration of Martian sand particles. The discovery breaks the long held belief that these giant dunes have not moved since they were formed hundreds of thousands of years ago.
according to science, Ralph Lorenz, a planetary scientist at the Applied Physics Laboratory of Johns Hopkins University, who was not involved in the study, said it was quite shocking that humans could detect these changes on Mars.
giant sand dunes can be found in the earth’s desert. The waves in the sand are separated by tens of meters, and they are an enlarged version of the ripples on many dunes that fluctuate every 10 cm or so.
Unlike sand dunes, giant dunes are composed of two different sizes of sand grains. Simone Silvestro, a planetary scientist at Italy’s National Institute of astrophysics, said thicker, heavier particles covered the top of giant dunes, making it harder for the wind to move them.
since the beginning of the 21st century, Mars probes and orbiters have repeatedly found giant sand dunes on this red planet. But they don’t seem to have undergone any measurable changes, leading some scientists to believe that they are relics of Mars’ past.
now, images taken by Silvestro and colleagues using NASA’s Mars Reconnaissance Orbiter show that some giant dunes are indeed moving slowly.
the researchers focused on two sites near the equator of Mars. They analyzed about 1100 giant dunes in the McLaughlin crater and 300 in the Nili fossae area. The researchers looked for signs of giant dune movement by comparing time-lapse images taken at the two sites 7.6 and 9.4 years apart. The study shows that the giant dunes advance about 10 cm a year in these two areas.
Jim zimbelman, a planetary geologist at the Museum of Aeronautics and Astronautics of the Smithsonian Institution, said the movement of giant dunes on Mars was surprising. Just a few decades ago, he said, there was no evidence that the sand on Mars was mobile, “we didn’t expect the wind to be so strong.”.
Silvestro and colleagues suggest that winds on Mars may be accelerating the formation of small sand grains. Once the sand begins to roll or bounce, it will hit the larger sand grains like a siege hammer and make them move.
the team believes that sand dunes on Mars may have contributed to the migration of giant dunes, because nearby dunes move in the same direction as giant dunes.
Silvestro plans to extend his research on the migration of giant sand dunes across Mars. He suspected that the fastest giant dunes would appear near the fastest moving dunes on Mars. The researchers believe that moving giant dunes are a sign of windy conditions, which could trigger sandstorms. Dust in the air can cover solar panels, reduce their efficiency, and attach to mechanical parts such as gears. This is bad news for Mars rovers and human habitats.