Researchers suspect underground water masses on Mars
Three billion years ago, vast amounts of water covered the surface of Mars. Today, none of it is visible. Contrary to previous assumptions, scientists now suspect, based on the analysis of a probe, that the water is buried kilometers deep. This discovery is significant, even though the water is not easily usable.
A team of scientists led by Vashan Wright of the University of California, San Diego, has discovered massive underground water reserves on Mars. The rock layers contain so much water at depths of 10 to 20 kilometers that it would be enough to fill a one to two kilometer deep ocean across the entire planet. The scientists made this discovery while analyzing data from the Mars probe "InSight".
"More than three billion years ago, there were large amounts of liquid water on the surface of Mars," explain Wright and his colleagues in the "Proceedings" of the U.S. National Academy of Sciences ("PNAS"). Evidence of this can be seen in numerous images of riverbeds, lakes, and a large ocean taken by Mars probes. After the planet lost most of its atmosphere, the water largely disappeared.
One theory is that Mars has lost about 90 percent of its water into space since then. Another theory is that a large part of the water may have seeped into the subsurface. To investigate this suspicion, Wright and his colleagues reanalyzed the data from "InSight" and compared it with various models of water-bearing rock layers.
The Mars probe, equipped with a seismometer, provided a glimpse into the interior of the Red Planet from 2018 to 2022. The propagation of seismic waves caused by Marsquakes or meteorite impacts provides researchers with detailed insights into the planet's internal structure.
Water is not easily usable, but indicates life
After analyzing the data, the researchers concluded that it is best explained by a water-bearing layer of magmatic rock at a depth of 10 to 20 kilometers. However, this water would be hardly usable for future Mars colonists - both due to its great depth and because the water is hidden in the pores and cracks of the rock and thus difficult to extract.
Nevertheless, such a rock layer would be significant. On Earth, even in great depths within the rock, one still finds microbes. "Water is necessary for life as we know it," emphasizes Wright's colleague Michael Manga. "Therefore, it is not unreasonable to suspect that the water-bearing rock layers on Mars could also provide a habitable environment for microbes." The team therefore sees these layers deep beneath the Martian surface as the primary target for the search for microbial life on our neighboring planet.
The discovery of massive underground water reserves on Mars suggests that the solar system's second planet once hosted significant amounts of liquid water. This finding adds to the ongoing debate about Mars' past and potential for harboring life, as water is considered essential for life as we know it.
