This Rock Just Rewrote 2 Billion Years of Mars
Keypoints:
- A meteorite called NWA 13441 was found in Algeria in 2019, but its age wasn't confirmed until this year
- Boston College researchers dated it to 1.273 billion years old
- That fills a roughly 1.8-billion-year gap in Mars's known volcanic record
- The rock's chemical signature traces back to the early solar system, unlike any other known Martian meteorite
- Findings were published in Geochimica et Cosmochimica Acta
Only about 400 Martian meteorites have ever turned up on Earth, and almost all of them cluster into two narrow windows of time, either quite young or extremely old. A newly dated rock from Algeria just cracked open everything sitting in between, a stretch of Mars's past nobody had a single sample from until now.
The meteorite, catalogued as NWA 13441, sat unexamined for years after its 2019 discovery, just another rock waiting its turn in a lab queue. Boston College researchers finally ran it through high-precision dating and landed on 1.273 billion years old, a number that matters far more than it sounds.
Most dated shergottites, the most common type of Martian meteorite, are either younger than 600 million years or roughly 2.4 billion years old. That left a nearly 1.8-billion-year stretch with zero direct samples, a genuine blind spot in everything scientists thought they knew about Mars's volcanic history.
Doctoral candidate Dylan M. Seal, who co-authored the study, put it plainly. This single rock fills a gap researchers simply had no way to look into before. The chemistry makes the find even stranger, in a good way.
The meteorite's neodymium isotope signature matches the early solar system itself, suggesting it formed from a pristine, previously unsampled pocket deep inside Mars, one that's apparently sat untouched since the planet first came together.
None of this means Mars went quiet during those missing 1.8 billion years, only that nobody had proof either way. Now, for the first time, they do.