NASA's Curiosity rover has unveiled remarkable evidence suggesting that Mars, now a desolate and arid landscape, once experienced seasonal climate changes that alternated between wet and dry conditions similar to those on Earth.
This revelation, derived from the rover's findings in the Gale crater, has opened up new possibilities that the red planet might have once harbored conditions suitable for life.
The Curiosity rover has been on a journey of exploration since 2012, with its recent focus on the Gale crater, which is believed to have housed a vast lake in the past. During its ascent of a sediment mountain within the crater, the rover stumbled upon formations of salt deposits, arranged in hexagonal patterns, in soil that dates back nearly four billion years.
Researchers have interpreted these patterns as cracks formed in dried mud, which then healed as the mud was submerged in water again. This phenomenon indicates repeated cycles of wet and dry seasons, marking "the first tangible proof that Mars had a cyclical climate," according to William Rapin, the lead author of the study.
These documented cycles of alternating wet and dry conditions could have provided an environment conducive to the formation of life. In the process of mud cracking and healing, the necessary conditions for the emergence of complex molecules, including organic compounds required for life, could have been present.