Orthogonoid
Orthogonoid  
View static image  
Pattern type  Spaceship  

Number of cells  467746  
Bounding box  868856×707  
Direction  Orthogonal  
Period  3476016  
Mod  1738008  
Speed  16c/217251  
Speed (unsimplified)  256c/3476016  
Heat  Unknown  
Discovered by  Dave Greene  
Year of discovery  2017  
 

The Orthogonoid is a selfconstructing spaceship analogous to the Demonoids, with a slow orthogonal direction of travel. The first example was completed by Dave Greene on 29 June 2017, with a top speed of 16c/217251 (this is just 256c/3476016 in lowest terms).^{[1]}
The construction recipe is a stream of MWSSes, with the recovery time limited to 90 ticks by the Lx200 dependent conduit that follows the initial syringe converter. The design is hashlifefriendly, meaning that the spaceship can be trivially adjusted so that spatial and temporal offsets are exact powers of two; period 4194304 and period 8388608 versions have been constructed, with speeds of c/16384 and c/32768 respectively. A script is available that can build any other sufficiently large Orthogonoid period.^{[2]}
The MWSSes are converted to Herschels, which produce a standard singlechannel glider stream that runs the Orthogonoid's single construction arm. After the child circuitry is complete, a previously constructed Snark in the parent is removed from the construction arm lane, converting it to a "destruction arm" that efficiently shoots down the previous constructor/reflector in the series as soon as it is no longer needed.
Fast Orthogonoids
In October 2018, Dave Greene and Adam P. Goucher built sparse, fast, HashLifefriendly Orthogonoids with speeds of c/128, c/64 and c/16. Greene noticed that the last of these could be accelerated to 65536c/951573, which is only marginally slower than the theoretical upper bound of c/12 (limited by the 2engine Cordership and 3engine Cordership).^{[3]}
The construction of this, together with a Demonoid and loopship, made extensive use of slmake.^{[4]}
References
 ↑ Dave Greene (June 29, 2017). Re: Orthogonoid working notes (discussion thread) at the ConwayLife.com forums
 ↑ Dave Greene (February 3, 2018). "Re: Orthogonoid spaceship  completed!". Retrieved on February 3, 2018.
 ↑ Dave Greene (October 28, 2018). "Re: Orthogonoid spaceship  completed!". Retrieved on November 25, 2018.
 ↑ Dave Greene (November 10, 2018). "New Tools for SelfConstruction". Retrieved on November 25, 2018.
External links
 Orthogonoid at the Life Lexicon
 Orthogonoid spaceship  completed! (discussion thread) at the ConwayLife.com forums
 Patterns
 Periodic objects with minimum population 1000 or more
 Patterns with 1000 or more cells
 Patterns found by Dave Greene
 Patterns found in 2017
 Patterns that can be constructed with 101 or more gliders
 Spaceships
 Spaceships with period 3476016
 Orthogonal spaceships
 Spaceships with speed 16c/217251
 Spaceships with unsimplified speed 256c/3476016
 Spaceships with mod 1738008