|View animated image|
|Number of cells||25|
|Discovered by||Jason Summers|
|Year of discovery||2000|
Crab (or quarter) is a diagonal c/4 spaceship that was found by Jason Summers in September 2000. It is the smallest known diagonal spaceship other than the glider and it consists of two gliders pulling a tagalong.
Due to the diagonal glide symmetry and by simple inspection, the spaceship can easily be made to stretch two tub wicks simultaneously. Both cases are instances of a domino dragging a tub or chain of tubs. Be it noted that tub chains are also called barges, and that additional non-stretching variants are possible given synchronized eating at the far ends.