Scientists have been collecting evidence to prove the previous existence of water on Mars. There are plenty of sites that may once have been oceans, lakes and rivers. With the help of equipment designed by the Johns Hopkins Applied Physics Laboratory (APL), researchers think they have discovered a crater that may once have been a standing lake fed by groundwater.
This information couldn’t have been discovered without the aid of the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM), which was built and is operated by APL. CRISM processes collected data while onboard NASA’s Mars Reconnaissance Orbiter (MRO).
CRISM operates by breaking up light into hundreds of individual colors, which can reveal the composition of the object being studied. The data from CRISM was analyzed and published in the online edition of Nature Geoscience. Joseph Michalski, who is affiliated with the Planetary Science Institute in Tucson, Arizona and London’s Natural History Museum, was the lead author of the paper.
What Michalski and his colleagues found was evidence that McLaughlin Crater, which is 57 miles in diameter and 1.4 miles deep, was once deep enough that underground water may have flowed into it.
This evidence consists of the presence of carbonates and clay minerals, the type of minerals that only form in the presence of water, encased in rocks at the bottom of the crater. The scientists believe that the carbonates formed in the presence of underground water. McLaughlin Crater doesn’t contain any large inflowing channels, which led researchers to claim that it couldn’t have gotten water from outside.
Furthermore, its smaller inflowing channels originate at a level in the crater wall where the surface of a lake could have been, suggesting that some water may have poured in from the crater wall and run into an already-existing lake. This indicates that McLaughlin Crater was once a wet environment and a possible habitat for ancient life.
McLaughlin Crater is located at the bottom of a very large regional slope, on the western side of the Arabia Terra region of Mars. This increases the feasibility of the idea that it was a groundwater-fed lake, since both Mars and Earth groundwater-fed lakes are expected to occur at low elevations.
Other studies done using CRISM data have found that rocks beneath the surface of Mars contain signs of hydrothermal fluids, further evidence that there was water underground. The groundwater then may have arrived at the surface of Mars in very deep basins such as McLaughlin Crater.
The scientists used CRISM to check for minerals such as carbonates in the rocks in the crater. The team that controls the MRO works closely with scientists around the world to procure the data samples they need to make new discoveries about water on Mars. The MRO was launched in 2005, and since then it has gathered more data about Mars than all the other Mars orbiters combined.
McLaughlin Crater has become a large interest for scientists and has been suggested as a future landing site for Mars missions. Although the presence of long-dead living organisms will be difficult to detect, if it’s true that there was standing water on the surface in places like McLaughlin Crater, it seems more and more likely that there may have been life on Mars.
