Three and a half billion years ago, waves and currents splashed across this dusty area on Mars now known as the Jezero Crater. On a nascent earth, chemistry coagulated towards the exalted state we call life.
Astronomers, philosophers and science fiction writers have long wondered whether nature carried out the same experiment there as it did on Earth. Was Mars just another test tube for Darwinian evolution? You will no longer be laughed out of biology class if you speculate that life actually first evolved on Mars and migrated to Earth on a meteorite, or that both planets were colonized with microbes or proto-life from an even more distant location.
So humans have sent their descendants across time and 300 million miles of space in search of long-lost relatives, ancient roots of a family tree that could be found in the soil of the Red Planet.
The Perseverance rover and its little sibling, the Ingenuity helicopter, landed in a cloud of sand full of antennas and cameras on February 18. Perseverance will spend the next Mars year – the equivalent of two Earth years – grazing, poking, and collecting stones from the Jezero crater and the river delta that penetrates it. The rover will chemically and geologically examine the debris and take photos so scientists on Earth can look for signs of ancient fossilization or other patterns that living organisms may have created.
Perseverance and ingenuity work on very long lines: 12 minutes of light travel time – and signal delay – across the airwaves of Pasadena, where their creators and tenders wait to see what they have recently achieved. Like the teenagers who let you out the door with your car keys, persistence and ingenuity are no more intelligent and responsible than people taught them to be.
These stones will be picked up and returned to Earth in a five-year series of maneuvers using squadrons, rovers, and orbital transfers starting in 2026, so locating the moon rocks looks as easy as sending Christmas cookies to your relatives. The rocks that return from 2031, like the Dead Sea Scrolls, will be studied for years for their hidden history of our lost twin and perhaps the earliest days of life in the solar system.
The generation after World War II carried out the first great reconnaissance of the solar system. It could be the fate of this generation to carry out the next great reconnaissance to find out whether we have or have ever had neighbors on these worlds. The dream lives on in the Jezero crater. We may never live on Mars, but our machines do.