NASA's Curiosity Rover, operational on Mars since 2012, has recently discovered signs of ancient ponds and lakes devoid of ice on the Martian surface. The rover identified small undulations resembling those found in sandy lakebeds on Earth, indicating that these features were formed by wind-driven water movement.
The findings suggest that the water was exposed to the atmosphere rather than being covered by ice, with the ripples believed to have formed approximately 3.7 billion years ago.
Mars, the fourth planet in the Solar System, exhibits a strong reddish hue due to iron oxide on its surface. Although it shares similarities with Earth, such as valleys and volcanoes, Mars has stark differences, including polar caps primarily composed of carbon dioxide ice and an inhospitable atmosphere.
The Curiosity Rover was launched by NASA in 2011 and arrived at Mars in August 2012, focusing on the Gale Crater region. Its primary mission is to explore the planet's climate and geology and to evaluate the possibility of past primitive life.
A recent study published in the journal Science Advances by researchers from Caltech revealed the discovery of two sets of ancient wave ripples on Mars, now recognized as remnants of dried-up water bodies. The team found that these ripples, which are typically formed by wind-driven water, provide compelling evidence that liquid water existed on Mars in the past.
The analysis indicates that the Martian atmosphere was once significantly warmer and denser, capable of sustaining liquid water. Computer models derived from the ripple measurements suggest that the ancient lake was shallow, potentially less than two meters deep.
The Prow outcrop, one of the identified ripple sets, was located in a region formerly characterized by wind-blown dunes, while the other set was found in the sulfate-rich Amapari Marker Band. These findings indicate that periods of a warm, dense atmosphere on Mars may have occurred multiple times.
This discovery contributes valuable insights to the study of Mars' paleoclimate, aiding in the understanding of the planet's evolving conditions. While NASA's Opportunity rover was the first to identify ripples on Mars, the nature of these water bodies remained uncertain until now. Further exploration is anticipated to determine the prevalence of such ripples across the Martian landscape.