NASA Scientists Just Discovered a 4.1-Billion-Year-Old Meteorite From Mars Hiding in Plain Sight - VICE

A chunk of rock found in the Sahara Desert that looks like a medium-rare filet mignon turned out to be neither just a rock nor a filet mignon. It’s actually a 4.1 billion-year-old chunk of Mars.

According to a paper published in Science, as detailed by the New York Times, a team of researchers led by NASA’s Jet Propulsion Laboratory analyzed the savory-looking rock, dubbed Teghaza 001. Discovered in 2022 near an ancient salt-mining settlement in Mali, the nearly two-pound meteorite is older than almost anything currently on Earth.

NASA scientists assumed the rock was just another boring, run-of-the-mill shergottite, a relatively young rock that was on Mars and, at some point, traveled to Earth via asteroid/meteor impact. They started to think differently when uranium-lead isotope dating revealed tiny zircon crystals inside the rock dated to roughly 4.1 billion years ago, back when Mars was a wet paradise and not the dry, foreboding symbol of our possible future.  

The rock is a terrific example of primordial Martian crust, as deep inside it hides phosphate minerals with apatite containing water molecules that came from deep magma rising out of the mantle and surface water that went deep into the crust.

Signs of Mars’ eventual descent into a rusty wasteland were already evident, even 4.1 billion years ago, as the sample shows Mars was already hemorrhaging its water into outer space as solar radiation broke apart liquid surface molecules.