When the ancients created the character for "valley," they looked upward into the spaces between mountains. In oracle bone script, its upper form resembles streams of water emerging from rocky cliffs, while below sits an opening, the mouth of the valley where waters begin their journey toward great rivers. Springs are born half-hidden among stones, flowing quietly downward.

In humanity's grand vision of colonizing Mars, the first Earth lifeform to set foot upon the red planet may not be human at all, nor some massive organism, but a tiny desert moss growing in the sands of Xinjiang, China: Syntrichia caninervis. Standing only a few millimeters tall, this fragile-looking species is reshaping our understanding of life's limits in ways that seem almost impossible, while offering humanity a humbler and more grounded path toward the stars.