Lacuna Before Dawn: A Shape That Sets the Burn

Before dawn, Lacuna draws three circles in the notebook. Inside the first, a round opening; inside the second, a star; inside the third, the spokes of a wagon wheel. Amber light catches the pencil dust. The window is still dark.

Beside each cross-section, Lacuna sketches a rough curve: burning surface against time. The circular opening suggests a surface that grows as it widens. The star and wheel ask for closer attention: points and spokes change as the material burns away, so the exposed area need not keep growing in the same way. Lacuna pauses over the curves, then makes one line lighter. These are comparisons, not predictions for a finished motor.

The shape is not simply a container for the fuel. It helps set the sequence in which that fuel is exposed. Other conditions matter, but the geometry alone can change whether thrust rises, holds roughly steady, or falls.

Lacuna lays the pencil across the notebook's margin and compares the three drawings in silence. Nothing on the desk moves. On the page, each opening contains a different way for time to unfold.