This week's featured article
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| 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.
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Pattern collection
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| The LifeWiki contains one of the most comprehensive catalogues of patterns available on the internet. Within it you will find:
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Did you know...
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- ... that the blinker is the only known finite oscillator that is one cell thick?
- ... that Gemini, the first spaceship found in Conway's Game of Life that travels in an oblique direction, was discovered in 2010?
- ... that there are still lifes (such as the quad pseudo still life) that can be split into four stable islands, but not two or three?
- ... that no new spaceship speeds were discovered between 1970 and 1989?
- ... that the first stable reflector was found in October 1996, and the first fast stable reflector appeared in 2013, allowing the construction of oscillators of all periods ≥43 ticks?
- ... that twenty-two spaceship velocities have been constructed, excluding several infinitely adjustable families of ships?
- ... that there are 71 distinct ways for two gliders to collide, but it is unknown how many distinct 3-glider collisions there are?
- ... that to display the smallest known gun pattern for a Gemini spaceship at 1 cell = 1 pixel, on a standard-density video monitor, a screen over one mile square would be needed?
- ... that no odd-period glider guns were known before 1995, when a period 565 p5-spark-assisted B-heptomino loop was constructed by David Buckingham?
- ... that even though the speed limit for spaceships is c/2 in a vacuum, in a medium of stripes agar there are "spaceships" that can travel at lightspeed along the stripes, or two thirds of lightspeed perpendicular to the stripes?
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