Life Puffer Trains

Puffer trains: c/2 orthogonal | c/12 diagonal | Geminoids
Wick-stretchers: c/4 diagonal
Puffers buildable from 5 gliders

Orthogonal c/2 puffer trains

These puffers are all based on the common c/2 orthogonal spaceships escorting various things.

The Coe and Schick Ship puffers are clean by themselves, but combining them produces a dirty puffer. Gosper's B-heptomino-based puffers also produce large messy exhaust plumes.

Other puffers can be constructed by adding appropriate escort spaceships to clean puffers, such as Coe ships or Schick ships to spark their normally-clean plumes to produce different output. Escort ships can also be added to most of the puffers shown here to alter their outputs as well. In fact, this is frequently done to puffers with large messy exhaust plumes.

c/2 orthogonal puffer trains

Schick Ship behind LWSS and LWSS with Coe engine (P240 exhaust) [15] Schick Ship behind HWSS and LWSS with Coe engine (P240 exhaust) [16] Wainwright's P8 blinker puffer [10] Buckingham's P24 tub puffer [9]
Gosper's P20 twin puffers (P180 exhaust) [11] Gosper's P20 puffer (P140 exhaust) [9]  

Diagonal c/12 puffer trains

These puffers are all various stabilizations of Corderman's c/12 diagonal Switch engine. The Switch engine is a natural puffer that flips and moves forward every 48 generations, effectively moving diagonally 4 spaces every 96 generations, for a net diagonal velocity of c/12. It produces a large messy exhaust plume. Unfortunately, moving so slowly, it is easily overcome by its own exhaust.

There are two known ways of stabilizing the exhaust by placing a single block behind the engine. One of these causes the engine to lay down sets of blocks each half-cycle (e.g. the "block-making switch engine"). The other produces a larger repeating plume that releases a forward glider (e.g. the "glider-making switch engine").

There are several ways that two switch engines moving in tandem can stabilize each other's exhausts. The first one found was called Noah's Ark, due to the large diversity of objects found in its plume. Subsequently, other arrangements have also been found, and these are collectively called Arks, after the first one.

It is possible to create "Corderships", i.e. clean spaceships with no exhaust, from three or more switch engines traveling in tandem.

c/12 diagonal puffer trains

Corderman's Block-making switch engine (P288 exhaust) [5] Corderman's Glider-making switch engine (P384 exhaust) [5] Noah's ark (P1344 exhaust) [8]


In November 2013, Dave Greene completed construction of several "Geminoid" constructors that work on the same basic principle as the Gemini spaceship, but with many technical improvements. In particular, rather than having two constructor arms as Gemini does, the Geminoids have only one. They are composed of a general constructor at one end (consisting of 39 eaters, 2 beehives, 2 boats, and 24 blocks), a stable glider reflector at the other (consisting of 13 eaters, 1 beehive and 7 blocks), and a data stream containing tens of thousands of gliders cycling in a loop in pairs, with the data itself encoded entirely in the timing of the gliders themselves.

These are instructions to the constructor to fire pairs of gliders in specific orientations at a distant simple still-life, oscillator, or constellation, to change them into a different still-life, oscillator, or constellation. After a sufficiently large number of steps, it is possible to place the simple constructor components (eaters, beehives, boats, blocks, and gliders) at almost any desired position. The constructor does not need to be universal; it only needs to construct these simple components, although slow-synthesis recipes currently exist for many other components, and others can be developed as the need arises.

Because these Geminoids do not destroy the original after making a copy, they are technically puffers whose output consists of copies of themselves, rather than true spaceships. However, it would probably not be too difficult to modify these to delete the original after making a copy, converting them into true spaceships.

The first of these begins with a population of 290096 (mostly gliders) in a 14826990x14826908 box. After 237228340 generations, the replicator returns to its original state, having created a child 256 cells straight up. The child is 277 generations delayed from the parent, so if this were to be converted into a spaceship, it would have a period of 237228617, and have a velocity of 256c/237228617, or approximately c/926674.

(Such slow movement is reminiscent of how plants move. While plants cannot move by themselves, a seed can advance slowly by growing into a full plant, which drops a seed a small distance from the original, starting the whole cycle all over again.)

The second of these folds the glider stream in half, so its population is also 290096, but its bounding box is only 7413639x7413557. Also, the replication takes half the time, so the replicator has a base period of 118614170, and the resulting spaceship would have a period of 118614447 and a velocity of 256c/118614447, or approximately c/463338.

The third removes half of the gliders (ones not containing data), and interleaves the first and second halves of the recipe, so its initial population is 145306 in a 3707102x3707020 bounding box.

Paradoxically, the first, even though the largest, runs fastest in Golly, because its gliders are spread so far apart, so they do not confuse the HashLife algorithm. The second is slower, and the third much slower.

Miscellaneous c/4 diagonal wick-stretchers

This is a small sampling of wick-stretchers that grow diagonally at a velocity of c/4.

c/4 diagonal wick-stretchers

Swan wick- stretcher [x] Tire Tracks [x] 157-bit wick-stretcher [x]

2 puffer trains buildable from 5 gliders

5-glider puffer trains

Corderman's Block-making switch engine (P288 exhaust) [5] Corderman's Glider-making switch engine (P384 exhaust) [5]

Other types: still-lifes, pseudo-still-lifes, oscillators, pseudo-oscillators, oscillators by period, pseudo-oscillators by period, guns, multi-colored Life, basic spaceships and pseudo-spaceships, exotic spaceships, spaceships flotillae, puffers, constellations, methuselahs, not quite stable objects.

See also: Life objects sorted by: counts, frequency of occurrence, cost in gliders, name, size in bits, or type.

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This page was last updated on 2015-02-19.