Curiosity uncovers Martian organics, hinting at ancient habitability

The Curiosity rover’s wet-chemistry experiment on a Mary Anning rock in Gale Crater detected 21 carbon-containing molecules—seven of which were previously unseen on Mars—including a nitrogen heterocycle, suggesting Martian rocks preserve organics for about 3.5 billion years and supporting a habitability history, though they are not direct signs of life and Earth-based sample return would be needed for a definitive answer.