By: James Neyer ~Staff Writer~
“Mars is not the dry, arid planet that we thought of in the past,” Jim Green, NASA’s director of planetary science, said to The Guardian. “Liquid water has been found on Mars.” Top NASA scientists confirmed that liquid water has been found on Mars at a press conference on Sept. 28.
During the summer months on Mars the water runs down canyons and crater walls, leaving long dark trails that can sometimes be hundreds of meters in length. These trails then dry up during the autumn months as surface temperatures drop. This evidence brings up questions about the possibility of life on Mars.
Looking for flowing water has been of utmost importance because it is the best place to look for life. In an Ask Me Anything (AMA) thread on Reddit, the deputy project scientist, Leslie K. Tamppari, said that it is possible.
“We know of forms of life that hibernate during dry seasons on Earth. The water that we’re seeing within the RSL (the seasonal dark streaks that we’re seeing on slopes on Mars) is salty. Salty water could be harmful to life,” Tamppari said.
The salt water on Mars is quite different from the oceans and seas on Earth. The salts detected in the water at the moment are magnesium or sodium perchlorate. These types are much less hospitable but are the reason that the water is able to remain liquid at much lower temperature.
“Liquid water, even if very salty, is still a good place to look for life forms,” Rich Zurek, chief scientist of NASA said in the AMA thread. “Water in any form is a resource that future missions could exploit,” he said. “We don’t know where the water in these hydrated salts come from. That is the next mystery to solve,” Tamppari said.
The briny water could come from various sources. Possible explanations given by Tamppari are the salts soaking up moisture from the atmosphere or the water coming up from under the subsurface. Scientists are not able to get a physical example of the water to test for multiple reasons. The first is that Curiosity, the Mars rover, was not sterilized to the necessary degree, meaning that it could have potential microbes that could contaminate such an environment with terrestrial life. In addition to that, the places in which the flows occur are too steep for present rovers to reach.
“Presently, NASA is looking into the possibility of sending humans to the vicinity of Mars in the early 2030s. In this scenario, the earliest humans to the surface would be in the late 2030s,” Zurek said.