NASA's Curiosity rover, which investigates the slopes of a Martian mountain, came upon several rocks with ancient water wave patterns.

The odd landscape was photographed in the middle of December 2022 by the car-sized robot Curiosity, which has been rumbling across Mars for ten years. The rocks have a similar undulating pattern to the wavy tracks shown when the water is briefly drawn back from a beach.

Expert Analysis

According to Mashable, researchers on the mission believe these grooves were made by waves lapping on the surface of a small lake billions of years ago. They hypothesize that the combed texture was created when silt was stirred up from below by the movement atop.

NASA's Jet Propulsion Laboratory's Curiosity project scientist, Ashwin Vasavada, said in a statement, "We climbed through thousands of feet of lake deposits and never saw evidence like this. Now we found it in a place we expected to be dry."

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Evidence of Water and Waves

There have been indications for a long time that Mars formerly had a thriving aquatic environment, complete with streams and lakes. The winding riverbeds and deep ravines of Mars were carved by the planet's water, leaving behind a hollowed-out landscape and a layer of dust.

In the first year of its mission, Curiosity transmitted home images of a dry, eroded stream bed with many smooth stones comparable to those created on Earth by moving water.

The relentless hunt for evidence of water on Mars, now a frozen wasteland, is an attempt to show that the Red Planet was once habitable and temperate, like Earth. Ancient Martian life may have required the presence of lakes and seas, but this is not definitive proof that the planet was ever really habitable. NASA plans to search for signs of ancient microbial life by investigating formerly wet places.

Nonetheless, petrified seabeds from eons ago provide another source of these water-imprinted rocks, which geologists may use to their advantage. For instance, the magnitude of the waves that caused the ripples and their spacing apart may be used to infer the depth of the water.

Unexpected Further Discovery

Since 2014, the rover has gradually ascended Mount Sharp, a three-mile-high summit with streams. Curiosity is creeping across the barren alien terrain, searching for microbes if they ever lived on Mars.

The robot spotted the rippling rocks on the Marker Band - a dark, thin band of granite wedged between lighter layers a half-mile up the mountain. Years before the rover launched, scientists discovered this natural landmark in orbiter photographs.

The mission crew never expected Curiosity to uncover further evidence of an old lake near the rover's present location, an area considered to have developed while Mars was drying. Salty minerals, perhaps from drying water, are abundant.

The rover will next visit a wind-carved valley to examine stones and trash that geologists believe were swept down the mountain billions of years ago. Scientists expect to find old water there.

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