NASA’s Curiosity rover has made several important discoveries and kept the people updated with its curated Twitter account.
The rover was launched almost 8 years ago on November 26, 2011, aboard an Atlas V541 from Cape Canaveral. The biggest and most capable rover ever sent to Mars landed in the Gale Crater on August 5, 2012.
The 150 km-wide crater is thought to have been a dry lake that had a whole lot more water 3.5 million years ago. The lake and its surrounding terrain from all those years have been described by scientists in a paper published in the journal Nature Geoscience.
Imagine Mars, 3.5 billion years ago. What did it look like? Findings from our @MarsCuriosity rover suggest that the Red Planet's Gale Crater might have been filled with waterways in the ancient past. Travel back in time: https://t.co/t2RFiR7FHA pic.twitter.com/uugMzPDbMN— NASA (@NASA) October 7, 2019
Mashable India reported that the crater is an ancient remnant of an asteroid impact that was filled layer by layer with sediments deposited by flowing water and wind.
Upon hardening, the sediment layers were carved by the wind into Mount Sharp that is being scaled by Curiosity today. Each layer is a representation of the different periods of Martian history which stores information about the environmental conditions in that time period.
NGeo: An interval of high salinity from evaporation of a palaeolake in Gale crater on Mars is inferred from bulk enrichments of Ca- and Mg-sulfates in sedimentary rocks analysed by @MarsCuriosity@EhlmannLabhttps://t.co/Nv11WPq3JS pic.twitter.com/7tiYEh82p1— Nature Geoscience (@NatureGeosci) October 7, 2019
NASA described that Curiosity discovered a section of sedimentary rocks that were rich with mineral salts, an indication that the crater had shallow briny ponds which overflowed and dried up multiple times.
The section describes that Martian environment transformed into a freezing desert but doesn't give an idea of how long the transformation took.
The 150 m tall section of sedimentary rocks has been dubbed ‘Sutton Island’ by the researchers. The ponds were similar to the saline lakes on South America's Altiplano as described by the lead researcher William Rapin, Caltech.
Mashable India also added that Curiosity will explore inclined layers in a distant region that is thought to have formed in an even drier condition called ‘sulfate-bearing unit’.
The region is very different from the deeper areas of the crater where evidence of persistent freshwater lakes were found.
If the rocks there did form in drier conditions over a long period, the clay-bearing unit that is being observed by curiosity is an intermediate stage.