KT9

One of the most fundamental questions in planetary science today is the nature of the ambient climate of early Mars (Noachian-Early Hesperian): Was the ambient climate “warm and wet/arid”, as suggested by widespread phyllosilicates, higher erosion rates, enhanced crater degradation, valley networks, and open/closed-basin lakes? Or was the ambient climate “cold and icy”, as suggested by recent climate models, with occasional perturbations causing heating and melting of surface snow and ice, and runoff to produce the observed characteristics and features? Using the framework of these two ambient climate options, we will discuss how NASA Mars Perseverance Rover at Jezero Crater open-basin lake, CNSA Tianwen-1 Zhurong Rover at Utopia Planitia and the 2022 ESA-Roscosmos Rosalind Franklin Rover to Oxia Planum will help to address these issues.