Often when we ponder the origins of life on Earth, we look to the another planet for answers. But the latest news from NASA’s Curiosity Mars rover suggests that the answers may be a lot closer than we think.
A new paper published in Nature has revealed evidence of wet-dry cycles occurring on early Mars. The findings were made by examining a patchwork of mud cracks found by Curiosity. The distinctive hexagonal pattern of these mud cracks suggests that the same conditions that created the cracks could have been favorable to the emergence of microscopic life.
This is an exciting development for scientists who are trying to understand how life began on Earth. We know that persistent cycles of wet and dry conditions on land helped assemble the complex chemical building blocks necessary for microbial life. Now, it appears that this same process could have occurred on early Mars as well.
The findings are also encouraging in regards to the potential for other forms of life in our universe. If wet-dry cycles can occur on Mars, it stands to reason that they can occur elsewhere in our universe as well. This may be good news for astrobiologists searching for other forms of life beyond our own planet.
Of course, more research is needed before we can draw any definitive conclusions about life on Mars or elsewhere in our universe. But these mud cracks offer a promising glimpse into a possible past on Mars – and a potential future for our own exploration of the universe.
A Journey Through Time on Mount Sharp.
Gale Crater, home to the Curiosity Rover’s mission, is a place of wonders and discovery. Curiosity has been steadily ascending the sedimentary layers of Mount Sharp, an impressive 3-mile-high feature in the crater. In 2021, the rover spotted mud cracks in a region between clay-rich layers and a higher region enriched with salty minerals called sulfates. This transitional zone offers us a glimpse into the past, when Gale Crater was filled with lakes and rivers and then experienced long dry spells.
The mineral composition of each region provides evidence about the different eras in Gale Crater’s history. As the mud dried out in this region, it shrank and fractured into T-shaped junctions. These were previously seen at “Old Soaker”, an area lower down on Mount Sharp. However, the recurring exposures to water in this transitional zone caused the T-shaped junctions to become Y-shaped and eventually form a hexagonal pattern. This hexagonal pattern is evidence that wet-dry conditions persisted over long periods of time, even as new sediment was deposited.
When Curiosity used its precision laser instrument, ChemCam, to investigate this region it discovered a hardy crust of sulfates along the cracks’ edges. This salty crust has helped preserve the mud cracks for billions of years. It is fascinating to think that what we are seeing today is evidence of conditions from so long ago!
The exploration of Gale Crater is teaching us more and more about our planet’s history and how environmental conditions have changed over time. We may not yet know all the answers, but Curiosity is helping us get closer to unlocking them. The journey of discovery continues on Mount Sharp!