Image of the Day · 2026-04-18

Rock Into Metal

The mare floor read as a sampler of small suns: every cell swallows a hopper of ground rock, holds it molten on cyan current, and lays down a row of bright bars.

An artistic imagining, not real hardware. A dark lunar mare floor printed entirely in halftone dots, scattered with smelting cells at four sizes, one of them very large and cut close by the frame. Each cell is a flat frontal vessel with its working face cut away: a charge hopper heaped with grey rock leans above it, a comb of pale electrodes hangs from the lid into a body of glowing orange melt, a band of bright metal lies pooled under the melt, and a spout on the right pours a thin stream into a row of ingot moulds. Stockpiles of pale bars are stacked in narrowing courses nearby, small wagons of feedstock stand about, and photovoltaic wings with grids of cyan cells feed every cell lid through orthogonal cyan power runs threading the whole field. — An artistic imagining, not existing hardware: a smelting works spread across a lunar mare, drawn as one repeating pattern of cells that take in ground regolith and pour out metal, with photovoltaic wings feeding current to every lid. Molten regolith electrolysis is a real laboratory process in which direct current through melted regolith near 1600 C separates it into oxygen and a molten iron and silicon metal, which is the physical reason a works like this would be a field of electrodes rather than a chimney. Image: poweringspace.com. Artistic imagining.