The Discovery of Mars: Composition, History, and the Search for Life

The Discovery and Mysteries of Mars: What We Know About the Red Planet

Mars has fascinated humanity for millennia. The ancient Babylonians recorded its movement across the night sky, and by the 17th century Galileo Galilei became one of the first to observe it through a telescope. Its reddish hue, caused by iron oxide (rust) on its surface, earned it the name “Red Planet” and fueled myths about alien civilizations.

Modern exploration, from NASA’s Mariner 4 flyby in 1965 to the Perseverance rover today, reveals Mars as a cold, desert-like world with a thin atmosphere made of 95% carbon dioxide. The planet is about half Earth’s size, with enormous volcanoes like Olympus Mons and vast canyons such as Valles Marineris. Water exists as ice at the poles and beneath the surface, hinting at a wetter past when rivers and lakes carved the landscape.

The search for life on Mars remains ongoing. While no active organisms have been detected, evidence of ancient water and complex organic molecules discovered by rovers suggests Mars may once have hosted microbial life billions of years ago. Today, harsh radiation, freezing temperatures, and lack of oxygen make surface life unlikely — but underground pockets of briny water may still harbor simple organisms.

Mars, once seen as a mythic war god, is now a scientific frontier — offering clues to our solar system’s history and a potential second home for humanity.