A spaceship (much less commonly referred to as a glider or a fish) is a finite pattern that returns to its initial state after a number of generations (known as its period) but in a different location. The speed of a spaceship is the number of cells that the pattern moves during its period. This is expressed in terms of c (the metaphorical "speed of light") which is one cell per generation; thus, a spaceship with a period of five that moves two cells to the left during its period travels at the speed of 2c/5. Most known spaceships in Life travel either orthogonally (only horizontal or vertical displacement) or diagonally (equal horizontal and vertical displacement). However, several large Conway's Life spaceships have been engineered that travel in various oblique directions, and it is known that Life has spaceships that travel in all rational directions at arbitrarily slow speeds.
September 14: ENDW’s first forum post contains an implementation of Goldtiger997's proposedomniship design with velocity (16,9)c/60 and period 600000000. This design allows the construction of spaceships for all non-orthogonal velocities strictly below the spaceship speed limit.
September 10-11: Nora Brownconstructs the first c/6 diagonal puffer, using a reaction by Hunter. iNoMedconstructs some smaller examples the next day. While c/6 diagonal puffers based on the Speed Demonoid design are possible, none have yet been constructed, and any such puffer would be much larger.
... that with reverse caber-tosseruniversal constructor technology, it is possible to build any possible glider-constructible pattern, no matter what size, using only 15 gliders?
... that there are at least four known ways to send information diagonally at a speed greater than the maximum spaceship speed through vacuum? (Complete mechanisms include speeds approaching c/2 via two perpendicular telegraphs, and 2c/3 via a 2c/3 wire.)
... that an oscillator with strict volatility 1 can be constructed for any period 945 or higher?
... that the original Gemini's "below-the-elbow" construction efficiency, roughly three gliders per still life, is about four times better than that of any subsequent self-constructingspaceship?
... that an O(sqrt(log(t))) pattern was constructed in 2010, with a diameter that grows at the slowest possible asymptotic ("big O") rate for any Life pattern?
