Lightweight spaceship
Lightweight spaceship  
View animated image  
View static image  
Pattern type  Spaceship  

Family  XWSS  
Number of cells  9  
Bounding box  5 × 4  
Frequency class  11.2  
Direction  Orthogonal  
Period  4  
Mod  2  
Speed  c/2  
Speed (unsimplified)  2c/4  
Heat  11  
Discovered by  John Conway  
Year of discovery  1970  
 
 
 

The lightweight spaceship (commonly abbreviated to LWSS) or (rarely) small fish^{[1]} is the smallest orthogonal spaceship, and the second most common spaceship after the glider. It moves at speed c/2 and has period 4 (and is therefore often referred to as 2c/4). It was found by John Conway in 1970.
Tagalong
In April 1992, David Bell found a tagalong for two lightweight spaceships (or two middleweight spaceships or two heavyweight spaceships). It can be extended indefinitely by attaching it to the back of itself. Interestingly, a hivenudger with symmetric rear (that is, both rear spaceships being of same "weight") can pull this tagalong.
Tagalong for two lightweight spaceships (click above to open LifeViewer) RLE: here Plaintext: here 
Commonness
 Main article: List of common spaceships
Random soups investigated by Achim Flammenkamp emitted one LWSS for approximately every 615 gliders.^{[2]} The LWSS is also the eighteenth most common object on Adam P. Goucher's Catagolue.^{[3]}
Glider synthesis
All strict still lifes with a population of 20 or fewer cells, as well as all oscillators and spaceships with 16 or fewer cells, are known to be gliderconstructible. A glider synthesis of this object can be found in the infobox to the right.
See also
 Fake xWSS
 Middleweight spaceship, Heavyweight spaceship, LWSS on MWSS 1, LWSS on HWSS 1
 Lightweight emulator
 Toaster
 Infinite LWSS hotel
 GtoLWSS
References
 ↑ "Small fish". The Life Lexicon. Stephen Silver. Retrieved on June 10, 2009.
 ↑ "Spontaneous appeared Spaceships out of Random Dust". Achim Flammenkamp (December 9, 1995). Retrieved on August 18, 2011.
 ↑ Adam P. Goucher. "Statistics". Catagolue. Retrieved on June 24, 2016.
External links
 LWSS at the Life Lexicon
 Life (B3/S23) at David Eppstein's Glider Database
 Lightweight spaceship at Adam P. Goucher's Catagolue
 LWSS on LWSS at Adam P. Goucher's Catagolue (pseudoobject)
 xWSS Tagalong at Adam P. Goucher's Catagolue
 The 1 ninebit spaceship at Mark D. Niemiec's Life Page
 9P4H2V0.1 at Heinrich Koenig's Game of Life Object Catalogs
 Patterns
 Patterns with Catagolue frequency class 11
 Natural periodic objects
 Spaceships with 9 cells
 Periodic objects with minimum population 9
 Patterns with 9 cells
 Patterns found by John Conway
 Patterns found in 1970
 Patterns that can be constructed with 3 gliders
 Spaceships
 Spaceships with period 4
 Orthogonal spaceships
 Spaceships with speed c/2
 Spaceships with unsimplified speed 2c/4
 Spaceships with heat 11
 XWSS variants
 Spaceships with mod 2
 Polyominoes
 Glide symmetric spaceships