SIMONS COLLABORATION ON THE ORIGINS OF LIFE
Earth’s fossil record suggests that by 3.5 billion years ago, life had found a footing on our planet. Yet the very processes that would shape the further evolution of that life — such as plate tectonics, erosion and weathering — also destroyed or muddled the crucial first records of life’s emergence, presenting a significant challenge for researchers trying to understand how life arose.
Mars, however, is seemingly inhospitable to life now but may not have always been so. And with nearly half of its surface rocks over 3.7 billion years old, Mars may have retained the records to show it. In short, 4 billion years ago, Earth had oceans and land, while Mars had wet climates and standing water, at least episodically. While one world went on to teem with life, the other may yet hold the key to understanding how life starts.