The main difference between an oscillator and a spaceship is that spaceships have translational motion and displace themselves over a period cycle, which oscillators do not do (oscillators can in fact be seen as spaceships with zero displacement). However, despite volatility and strict volatility being well understood and assigned to oscillators, there does not appear to be any such definitions for spaceships (at least not that I can find by searching on the forum).
There do appear to be cases in which a definition of strict volatility would be useful for spaceships. Here, for example, is the weekender:
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x = 16, y = 11, rule = B3/S23
bo12bo$bo12bo$obo10bobo$bo12bo$bo12bo$2bo3b4o3bo$6b4o$2b4o4b4o2$4bo6b
o$5b2o2b2o!
[[ AGESTATES 7 ]]
The following is Garth's period-21 "doo-dah" spaceship:
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x = 16, y = 28, rule = B3/S23
bo12bo$bo12bo$obo10bobo$bo12bo$bo12bo$2bo3b4o3bo$6b4o$2b4o4b4o2$4bo6b
o$5b2o2b2o6$3b2o6b2o$2bob2o4b2obo$2bo2bo4bo2bo$3b3o4b3o$3b2o6b2o2$o14b
o$o14bo$bo12bo$b2o10b2o$o14bo$b2o10b2o!
We can overlay three copies of this spaceships seven generations apart on top of each other using TripleB3S23 for a clearer picture of this phenomenon:
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x = 32, y = 35, rule = TripleB3S23
2$8.G12.G$8.G12.G$7.G.G10.G.G$8.G12.G$8.G12.G$9.G3.4G3.G$13.4G$9.4G4.
4G2$11.G6.G$12.2G2.2G3$11.2B4.2B2$10.2FD4.D2F$10.EGDB2.BDGE$9.ADAE4.E
ADA$8.DE2.A.2B.A2.ED$8.2D2CAB2.BA2C2D$7.D2.EA.B2DB.AE2.D$6.2B2D4.2F4.
2D2B$7.C14.C$7.C4.B4.B4.C$8.C.B8.B.C$8.EC10.CE$7.A.D10.D.A$7.DAE10.EA
D$8.D12.D!
Many other cases of low-period spaceships with higher-period tagalongs can be seen to exhibit similar such behaviour.
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x = 28, y = 28, rule = B3/S23
5b2obo7b3o$5bo3bo6bo$5bo4bo7bo7b2o$7b2o7bobo4b2obo$9bobo4b3obo2b2o$3o
12bo3b2o2b2o$o10b2ob4ob2o$3bo8b7o$o2bo$bo2bo$2bo$4bobo$6b2o$7bo6b3o$6b
2o6bo2bo$5b3o5bo3bo$2ob2ob2o7bo$o3bob2o9b2o$ob3o2bo5bo6bo$5b2o8b3o3bo$
4b3o14bo$19bo$20bo$3b3o$3b3o2$2b2o$2bo!
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x = 21, y = 14, rule = B3/S23
6b3o3b3o$2bob2o3bobo3b2obo$b3o3bobobobo3b3o$o3bo4bobo4bo3bo$bo7bobo7bo$8bobob
o$8bobobo2$10bo$9bobo$7b2o3b2o$7b2o3b2o$6bo7bo$7bo5bo!
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x = 111, y = 148, rule = B3/S23
66b2o$65b2ob2o5b3o$65bo2b2o10bo$65b4o6b2o3b3o$65b2o4b2o3b2o2bobo$65b2o
4b2o3b2o2bobo$65b4o6b2o3b3o$65bo2b2o10bo$45b2o18b2ob2o5b3o$45bobo6b2o
2bo7b2o18b2o$44bo2b2o5b2obo2bo25bobo6b2o2bo$22b2o21b2o3bo4bo4bo24bo2b
2o5b2obo2bo$22bobo6b2o2bo9bo5bo4bo2bobo24b2o3bo4bo4bo$21bo2b2o5b2obo2b
o7bo5bo4bo2bobo24bo5bo4bo2bobo$22b2o3bo4bo4bo7b2o3bo4bo4bo25bo5bo4bo2b
obo$22bo5bo4bo2bobo5bo2b2o5b2obo2bo25b2o3bo4bo4bo$22bo5bo4bo2bobo6bobo
6b2o2bo26bo2b2o5b2obo2bo$22b2o3bo4bo4bo7b2o39bobo6b2o2bo$21bo2b2o5b2ob
o2bo48b2o$b2o19bobo6b2o2bo$bobo6b2o2bo7b2o$o2b2o5b2obo2bo$b2o3bo4bo4bo
$bo5bo4bo2bobo8b2o8b2o20b2o$bo5bo4bo2bobo8b2o8b2o20b2o$b2o3bo4bo4bo$o
2b2o5b2obo2bo77b2o$bobo6b2o2bo79bobo6b2o2bo$b2o90bo2b2o5b2obo2bo$94b2o
3bo4bo4bo$94bo5bo4bo2bobo$13b2o6b2o22b2o6b2o39bo5bo4bo2bobo$13b2o6b2o
22b2o6b2o39b2o3bo4bo4bo$93bo2b2o5b2obo2bo$94bobo6b2o2bo$94b2o$34b2o$
34b2o2$82bo$17b2o63b2o$17bobo6b2o2bo50bobo$16bo2b2o5b2obo2bo$17b2o3bo
4bo4bo$17bo5bo4bo2bobo$17bo5bo4bo2bobo$17b2o3bo4bo4bo$16bo2b2o5b2obo2b
o$17bobo6b2o2bo$17b2o17$57bobo$58b2o$58bo30$17b2o$17bobo6b2o2bo$16bo2b
2o5b2obo2bo$17b2o3bo4bo4bo$17bo5bo4bo2bobo$17bo5bo4bo2bobo$17b2o3bo4bo
4bo$16bo2b2o5b2obo2bo$17bobo6b2o2bo$17b2o5$94b2o$94bobo6b2o2bo$93bo2b
2o5b2obo2bo$5b2o22b2o6b2o30b2o23b2o3bo4bo4bo$5b2o22b2o6b2o30b2o23bo5bo
4bo2bobo$94bo5bo4bo2bobo$94b2o3bo4bo4bo$b2o90bo2b2o5b2obo2bo$bobo6b2o
2bo47bobo29bobo6b2o2bo$o2b2o5b2obo2bo44bo3bo28b2o$b2o3bo4bo4bo43bo4bo$
bo5bo4bo2bobo24b2o16bo4bo8b2o$bo5bo4bo2bobo24b2o16bo3bo9b2o$b2o3bo4bo
4bo44bo2bo$o2b2o5b2obo2bo$bobo6b2o2bo7b2o$b2o19bobo6b2o2bo$21bo2b2o5b
2obo2bo48b2o$22b2o3bo4bo4bo7b2o39bobo6b2o2bo$22bo5bo4bo2bobo6bobo6b2o
2bo26bo2b2o5b2obo2bo$22bo5bo4bo2bobo5bo2b2o5b2obo2bo25b2o3bo4bo4bo$22b
2o3bo4bo4bo7b2o3bo4bo4bo25bo5bo4bo2bobo$21bo2b2o5b2obo2bo7bo5bo4bo2bob
o24bo5bo4bo2bobo$22bobo6b2o2bo9bo5bo4bo2bobo24b2o3bo4bo4bo$22b2o21b2o
3bo4bo4bo24bo2b2o5b2obo2bo$44bo2b2o5b2obo2bo25bobo6b2o2bo$45bobo6b2o2b
o7b2o18b2o$45b2o18b2ob2o5b3o$65bo2b2o10bo$65b4o6b2o3b3o$65b2o4b2o3b2o
2bobo$65b2o4b2o3b2o2bobo$65b4o6b2o3b3o$65bo2b2o10bo$65b2ob2o5b3o$66b2o
!
Code: Select all
x = 130, y = 133, rule = B36ce7c/S23-y
103bo$102bobo$102bo2bo$100b2obob2o$100b2obob2o$101bob2obo$102b4o$104bo
34$100bo$99b3o$98bo2bo$97b5o$98bo2bo22b3ob2o$99bob2o22bobobo$101bo23bo
3bo$126bobo$127bo8$115bo$115bo2b2o$115bo2b2o3$68bo$68b3o$68b3o40bo$69b
obo38bobo$65b3o45b2o$66b2o40bo2bo$66bo3bo40bo3bo$108b2o4bo$98b2o10bo$
100bo11b2o$97bo2bo$99bobo$96b3o$97b5o$100bo3$47bo$44bo3b2o$47b3o26b2o$
48b3o24bo$45b2o28b3o$44b3o29bo$46bo31bo$29b2ob2o20b2o21b3o$29b2obob2o
17bo2bo20b6o$29bobo3bo18b2o25b2o$34b2o2$31b3o4$2bo$2b2o49bo$b2ob2o46bo
bo$bo51bobo$3o3bo43bo2b2o$3bo46bo4bo$4b2o13b2o29bo3b2o$o18b2o31bob2o$b
o17b2o2$19b3o88bo$108bo3bo$104bo3bo3bo$102bobo4bo3bo$103b2o5bob3o$45bo
60bo3b3o$43b2obo60bo2bo$43bo3bo$44bobo$6b3ob2o$10b2o9$35b3o2bo$39b2o3$
24b2o$24b2o$24b2o2$24b3o!
In addition, volatility is only considered for oscillators with periods 2 and above, since period-1 oscillators are classified as "still lifes" and given their own pattern class. However, period-1 spaceships are still considered spaceships and are not given special treatment. We'd have to ask ourselves: would a still life have a volatility of 1 since all constituent cells oscillate at the "full period" of 1, or would they have a volatility of 0 since every cell is a stator? Questions like this must be answered if spaceships like the "moon" were to be assigned values for volatility, since every single cell dies every generation though the configuration appears identical overall:
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x = 2, y = 4, rule = B2ae/S
o$bo$bo$o!
There's also the far-future concept of spaceship period maps analogous to oscillator period maps that one could consider - but let's not get into that now.
Discuss!