Stable Storage Spaceship

Stable Storage Spaceship
View static image
Pattern type	Spaceship
Number of cells	633388
Bounding box	5123883 × 5123663
Direction	Oblique
Slope	200/7
Period	81976184 (mod: 81976184)
Speed	(200,7)c/81976184 | (200,7)c/81976184
Heat	Unknown
Kinetic symmetry	Unspecified
Discovered by	Goldtiger997
Year of discovery	2023
Rules Outer-totalistic rules B3/S23 only # of rules 20 = 1 Isotropic rules B3/S23 only

The Stable Storage Spaceship is an oblique constructed spaceship. It was completed by Goldtiger997 and finalised on June 2, 2023. In its initial phase, it consists of a single glider and a 633523-cell stable constellation.

The spaceship's initial population is 633,528. It reaches the minimum of 633,388 shortly after the beginning at generation 907.

The Stable Storage Spaceship uses a clever shortcut to minimize the amount of complex tape-reading circuitry. There's a static tape consisting of the presence or absence of boats at regular intervals -- but there's no "read arm" and no separate READ and COPY stage for each cycle. Instead a seed is constructed for a mobile "read head" consisting of a paired Corderpuffer and Corderrake, which passes by the boats encoding the construction recipe and moves them by (200,7) while also converting them to gliders on a particular lane, aimed back to the starting point to activate the construction arm.

The construction arm consists of nothing more than a period-256 glider gun and a p8 bumper. It's designed to produce the same glider-pair spacing as the native RCT construction arm, and it turns out that many of the same elbow operations still work, even though the relative timings of the gliders in the pairs is a bit different. So the Stable Storage Spaceship, like the RCT, relies on the fact that universal construction can be achieved by a long enough series of free choices between sending a singleton glider vs. sending a pair of gliders on lanes separated by 6 half-diagonals, aimed at a construction elbow object.