This week's featured article
| 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.
| The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:
Did you know...
- ...that c/2 orthogonal and c/4 diagonal are the only speeds of spaceships seen to emerge from asymmetric soups on Catagolue?
- ...that all currently known standard Herschel conduits produce the same Herschel great-grandfather pattern, except for Fx158?
- ...that eater 1 is the smallest asymmetric still life?
- ...that in Life, no spaceship can exist with a speed of (m,n)c/x where (m+n)/x > 0.5?
- ... that an N-bit strict still life – specifically, some length of long long (...) boat or barge – can be constructed for any odd integer N using no more than 39 gliders, and for any even integer N using no more than 38 gliders, using a temporary tubstretcher?
- ... that an N-bit period-2 oscillator can be constructed for any odd integer N using no more than 45 gliders, and for any even integer N using no more than 46 gliders, using a temporary tubstretcher?
- ...that it is currently an open question as to if there exists a periodic pattern whose only predecessors are its own evolutionary sequence?
- ...that it can be proved reflectorless rotating oscillators exist in Life, although none have yet been found or constructed?
- ...that there are currently known elementary spaceships with speeds c/7 and c/10 orthogonal, but none with c/8 or c/9?
- ...that there are currently known elementary spaceships with speeds c/7 and c/12 diagonal, but none with c/8, c/9, c/10 or c/11?