At the edge of Mars's gravitational neighborhood, a small, irregular moon called Deimos drifts in a kind of celestial quietude, its gravity so faint that the speed needed to orbit its surface matches the pace of a competitive racewalker. This is not merely a curiosity of scale — it is a reminder that the universe contains bodies so diminished in mass that our familiar intuitions about weight, force, and escape dissolve into something almost philosophical. Deimos asks us to reconsider what it means to be held by a world, and what it might mean, one day, to walk upon one that barely holds you at