It’s possible that an old Red-Planet rover is spotting evidence of the Martian climate drying up in the past.
The lengthy NASA Curiosity mission, which will mark its tenth Earth-year anniversary on Mars this August, is climbing Mount Sharp’s (Aeolis Mons) slopes to study how Mars’ temperature has changed throughout the ages. Curiosity has been seeing a transition zone packed with salty sulphate as water-rich clay gives way over the course of the last year or so of its roaming. According to a NASA release, scientists currently assume those markings indicate the locations where streams dried up and sand dunes developed (opens in new tab).
This indicates that when Curiosity ascends higher on the mountain, lake deposits that once covered the lower slopes are less prevalent. Ashwin Vasavada, Curiosity’s project scientist at JPL, said in the release, “Instead, we see lots of evidence of drier conditions, such dry dunes that occasionally had streams running around them.”
