Mysterious mounds have been found on Mars, revealing that the Red Planet was once completely different. Check out the intriguing images!

Scientists have discovered thousands of hills and mounds on Mars, made up of layers of clay minerals formed by the interaction of flowing water with rocks, during a time when an ancient ocean existed in the northern part of Mars. New research indicates that in the distant past, Mars had a completely different climate, with a significant amount of liquid water present on the surface of the Red Planet nearly 4 billion years ago. The findings of the study have been published in the journal Nature Geoscience, reports Space.

The two hemispheres of Mars are distinct from one another. The southern hemisphere features ancient highlands, while the northern hemisphere consists of low plains that have been altered by erosion, where scientists believe an ocean existed in the distant past. There is now substantial evidence that Mars was much warmer and had rivers, lakes, seas, and possibly even oceans around 4 billion years ago.

Researchers have now found new evidence supporting the existence of an ocean in the northern part of Mars, linked to the discovery of over 15,000 hills and mounds rising up to 500 meters, which contain clay minerals.

On Earth, such topographical features in the form of hills and table mountains can be found in desert regions, where rock formations have been eroded by wind over millions of years. Similar formations have been identified on Mars, utilizing data from the Mars Reconnaissance Orbiter, Mars Express, and Trace Gas Orbiter.

Scientists believe that the thousands of hills and mounds are remnants of a highland that has retreated hundreds of kilometers and has been eroded by water and wind in a vast lowland area known as the Chryse Planitia.

They found that the mounds on Mars consist of layers of clay minerals, which form when liquid water interacts with rock over millions of years. Researchers suggest that a large body of water, possibly a northern ocean, existed on the surface of Mars.

Below and above the clay layers, scientists discovered older and younger rock layers, respectively, which do not contain clay. They believe that the clay minerals date back to a period in Mars' history when liquid water was present on the surface, specifically between 4.2 and 3.7 billion years ago.

According to the study's authors, the Rosalind Franklin rover is set to land in this region, scheduled to launch to Mars in 2028. This rover will help determine whether an ocean existed on Mars, and if so, whether extraterrestrial life could have existed there.