Edge-repair spaceship 1 is a c/3 orthogonaledge-repairspaceship that was found by David Bell in 1992. It was the first edge-repair spaceship to be discovered, though the usefulness of its edge-repair property was not recognized until July 1997. This edge repair spaceship can be used to perturb various debris from puffers to create puffers or spaceships of different periods. Edge repair spaceships can also remove some stationary objects, most notably, two edge-repair spaceships can delete a block. The edge-repair component of this ship is used in much of the known c/3 technology, although one sometimes has to use a different ship to allow the edge-repair component to be accessible.
goldenratio found a final step for a synthesis of this spaceship on January 24, 2021, which bubblegum made a complete synthesis out of soon after.[1] Various improvements were posted over the next few days,[2][3][4][5] eventually making ERS1 the cheapest period-3 spaceship to synthesize as of January 27.[6]