If aliens existed on Mars 3.7 billion years ago, they would have needed umbrellas

A network of ancient, inverted river channels spanning over 9,000 miles has been found in Mars' Noachis Terra region, indicating the planet was once wetter than believed. The channels, formed by sedimentary deposits, suggest stable climate and significant precipitation around 3.7 billion years ago. This discovery, based on NASA's Mars orbiter data, provides evidence that Mars was once more Earth-like and challenges previous assumptions about its geological history.