NASA’s Mars Insight Lander landed on the planet in 2018. The lander carried a seismometer that recorded four years of vibrations—Martian ground motion—from deep within the Red Planet. Analysis of these tremors and the planet’s subtle motion revealed seismic signatures of liquid water.
Although samples of frozen water and vapor have previously been found in the atmosphere at the poles of Mars, this is the first time liquid water has been found on the planet.
The results were published in the journal Proceedings of the National Academy of Sciences.
InSight's science mission ended in December 2022 after the lander listened to the “pulse of Mars” for four years. During that time, the probe recorded more than 1,319 tremors.
Scientists measured how fast seismic waves traveled, and then calculated the materials through which the vibration was most likely to travel.
“These are actually the same methods we use on Earth to search for water, oil and gas,” explained Professor Michael Manga, a UC Berkeley fellow who participated in the research.
During the analysis, water reservoirs were discovered in the Martian crust, at a depth of about 10-20 kilometers.
“Understanding the water cycle on Mars is key to understanding the evolution of climate and surface,” said lead researcher Dr. Fashan Wright of the Center for Oceanography and Geosciences at the University of California, San Diego.
– Water is the most important molecule in the evolution of the planet. This discovery may also answer the big question of where all the water on Mars went He told BBC News.
A study of the surface of Mars with its various channels and waves shows that in ancient times there were rivers and lakes on the planet, which was a desert three billion years ago.
Some of the water is thought to have been lost to space when Mars lost its atmosphere. However, according to Professor Manga, since most of the water is also found underground on Earth, there is no reason to assume that this would not be the case on Mars as well.
InSight was only able to image the crust directly beneath its base, but researchers believe similar reservoirs exist all over the planet. If that’s the case, they estimate Mars has enough liquid water to form a layer more than half a mile deep on the surface.
The findings also suggest that the location of groundwater on Mars is not good news for billionaires with plans to colonize Mars who might want to take advantage of that water.
– This fluid is trapped 10-20 kilometers deep in the Earth's crust. Professor Manga said that drilling a hole 10 kilometers deep on the surface of Mars would be difficult even for Elon Musk.
This discovery also provided new evidence in research in other areas, such as the search for evidence of life on Mars.
“Without liquid water there is no life.” So if there were habitable areas on Mars, they may now be deep underground, the professor said.
