Many scientists believe that what we have seen from satellite and rover images of the Red Planet — and what we will see when we land humans on its dusty surface — is a shadow of what it was billions of years ago. The results of two new studies could mean what we are looking at now is really the skeleton of a once-fertile planet that may have even been swarming with alien life-forms.
Meteorites unearthed clues about the formation of Mars and its early existence, and this was the focus of the first study, published in Nature. Mars is thought to have fully formed some 5 million years after our solar system was born, and the nascent planet’s crust was assumed not to have solidified for another hundred million. Martian meteorites that broke off its crust and crashed to Earth carried clues about how this planet that is now seemingly all but dead came into being.
Zircons found in these meteorites revealed that they are around 4.476 billion to 4.430 billion years old, which means that the Martian crust solidified in 20 million years or less after planetary formation, the same length of time it took for its core to form, though there is a chance the early crust could have melted and re-solidified within a hundred million years after the planet formed. So what does this mean when you compare Mars to our planet?
“These zircons, which are about 100 million years older that the oldest terrestrial zircons, tell us that Mars had evolved into a fully differentiated planet with a crust much earlier than Earth,” University of Copenhagen cosmochemistry professor Martin Bizarro told Gizmodo.
Figuring out where that particular meteor came from will be another challenge that may eventually involve human astronauts collecting data from the Martian regolith.
The second study, published in Science Advances, backed up something that has been long suspected and investigated. Those bizarre channels on Mars, which are thought to be the ghosts of rivers that have long since dried up, seem to mirror networks of rivers running through the dryer regions of Earth. Researchers concluded that these couldn’t possibly be the work of groundwater. Think melting glaciers—or rain.
“You need meltwater, or you need precipitation,” ETH Zürich professor Hansjörg Seybold said regarding what could have carved the channels out. “We would then hypothesize that Mars’ past climate had an active hydrologic cycle.”
If this hypothesis holds water, that means that ancient weather forecasts for Mars would have predicted rain. They just wouldn’t have been televised.
As we think of Mars more and more like Earth, could that mean there are fossilized alien creatures lurking under its crust? We haven’t gone there yet, but considering how primordial earth was seething and writhing with microbes, it’s a possibility.