Scientists are studying Mars intently and know that in its distant past, the planet had water. The question the scientists want to answer is was the water that was present on the Red Planted frozen in ice, or was it liquid and flowing. Warm conditions would make life more likely.
Scientists have used a new comparison of mineral deposits found on Mars to those found on Earth. The comparison lends weight to the idea that on the surface of ancient Mars, there were one or more long periods where the planet had rainstorms and flowing water.
The water later froze according to the team. The challenge now for the researchers is figuring out when the planet had flowing water and when it was frozen. One major challenge to determining this is that we’ve never sent missions to the areas where the earliest rocks that might answer these questions are located.
That means that the team has to use science that works from Earth to answer the questions. Scientists know how different climate conditions affect rock, they know this from studying drastically different conditions in places like the Oregon Cascades, Hawaii, Iceland, and other locations. That study has shown how climate impacts the pattern of mineral dispersion.
On Earth, silica deposition in glaciers is found and signals a characteristic of melting water. In younger areas of Mars, scientists have found similar silica deposits. Older areas of Mars show deep soils that are found in warmer climates on Earth. The team says that these findings led it to believe that there was a slow trend from warm to cold with periods of thawing and freezing on Mars 3 to 4 billion years ago. One challenge is that while the surface of the planet shows this cooling trend, the climate models don’t so the scientists have to work on the existing climate models.
Image credit: NASA/JPL-Caltech/University of Arizona