Gravity, ST, and Terrans on Mars

[Ze'Manel Cunha]

Originally Posted by Grey_Fox

I second this, it would seem that in an environment with a lower gravity then earth the native inhabitants would require less ST in general and hence have lower hit points. So a typical Terran will seem much stronger and tougher than a typical Martian, also on Mars a Terran will seem a lot stronger than he normally is on Earth and on Earth a Martian will seem a lot weaker than he is on Mars.

This works whether you are talking about native (alien) Martians that have evolved on Mars or whether you mean human settlers on Mars, for evolution is just a case of being adjusted to the environment and for humans it’s a case of Wolff’s Law and similar principles that apply to muscle.

Yep, you'd likely have Martians with very light bones, bones which if you exposed them to Earth like gravity would be more prone to breaking, in the same way human bones would tend to break in 3Gs without time to adjust.

The question of whether Martians would be more likely smaller and lighter or taller and heavier is probably more dependent on atmospheric pressure and other competitive resource conditions than just the gravity itself.

Personally I'd go with smaller and lighter, not that flying whales don't have a certain appeal.

[Fred Brackin]

Originally Posted by Stripe

After reading p. B350, I think you'll agree that Edgar Rice Burroughs' John Carter was a highly-cinematic character.

You may wish to give a Carter-like Superman a little extra ST, but more importantly Striking ST (p. B88). You may wish to give him Tough Skin (p. B47) as well. I've only read the first Barsoom novella, and that was long time ago, but if I remember correctly, Carter could split a Green Martian's skull with a punch pretty easily. IIRC, he killed more than one with his bare hands.

Not a split skull. The Green Martian in question backhanded Dejah Thoris and Carter spontaneously invented the Flying Uppercut leaping straight upward 15 feet and smacking the Greenie in the jaw, killing him either with a broken neck or a fatal concussion.

Actually statting out a Flying Uppercut (which is to a regular Uppercut as a Flying Jump Kick is to a regular Jump Kick) is an interesting exercise in G;Martial Arts but Carter was obviously using some Cinematic rule or other that lets you claim Critical Hits when necessary.

The leaping 15 feet straight up is pretty cinematic too. the reason why it is and the tricky thing if you're actually trying to be realistic is that "weight" or perhaps more properly gravitaional mass varies according to the local field but _inertial_ mass remains the same wherever you go.

The way this translates into Gurps is that Lifting ST manipulates weight but Striking ST (and Min ST for weapons) works on inertial mass. On Earth these are the same according to out locally normed eyes but on Mars they are different.

If youwere really a masochist you could give a human-looking Martian a -4 to Lifting ST but normal Striking ST. A compromise would be to average the two. 38% lift plus 100% striking comes to slightly more than a combined ST of -2 or 64% BL.

This might be okay as Min ST for a Rapier or a Shortsword is 8. HP should be nromal for sT when doing things the simple way or tied to Striking ST when being complex. As humans don't actually have two independant sets of muscles I favor the combination method.

Movement also stays normal as it's largely based on inertial mass. Trazlistically there should be some effect on jumping but that's only because while you can't leap any _faster_ you fall back down more slowly. Potentially very complicated to handle realsitiically.

If I was actually trying to do Barsoom I'd make Barsoomians "normal" and Carter Super-Barsoomian with ST around 30 and 1 or 2 levels of Super Jump.

[Agemegos]

Originally Posted by malloyd

Not for any obvious reason. But if you want them to, just give Martians a -4 racial ST, which allows them to lift about the same objects on Mars humans could lift on Earth, without changing their mass from human normal. Problem solved.

I wouldn't go all the way to -4. Lifting capacity is cheaper in low gravity, so you would expect evolution to "buy" more of it, splitting its gains between some metabolic savings and some increased capability. Where exactly the equilibrium lies is imponderable, but on general principles it ought to be somewhere in between equal strength in force exertible and equal strength in mass liftable.

[isf]

Originally Posted by lexington

See the "Different Gravity" rules on page 350 of Basic Set. One thing they don't mention that might be important is MinST for weapons, which should probably scale the same way.

I had missed that (I was looking in Space and Biotech).

Originally Posted by lexington

If you want to reflect something like Martians being tall and spindly because of the low gravity give them Vulnerability (Crushing, x2) [-30].

I don't know if I'll use this, but I like it.

[isf]

Originally Posted by malloyd

It doesn't. The weight of things changes on a higher or lower gravity world instead. Your BL stays exactly the same, but the same objects weigh less on Mars, so you don't need as high a BL to lift them. I can't see any reason you would want to go the other way.

I was thinking about how Terrans would look like from a Martian perspective and wondered if it would be similar to how we would see some humanoid from a 2.5G world.

Originally Posted by malloyd

Not for any obvious reason. But if you want them to, just give Martians a -4 racial ST, which allows them to lift about the same objects on Mars humans could lift on Earth, without changing their mass from human normal. Problem solved.

I'll need to scale various Martian equipment anyway since the proportions are different from humans.

Originally Posted by malloyd

I really think you are trying to scale the wrong thing if you are trying to keep Martians at ST 10.

So it appears that the rules on B350, don't treat the differences between Mars/Terra and Terra/2.5G world as the same. Penalties for differeng gravity penalize the 2.5G native on Earth more than the Terran on Mars.

[vitruvian]

Originally Posted by malloyd

It doesn't. The weight of things changes on a higher or lower gravity world instead. Your BL stays exactly the same, but the same objects weigh less on Mars, so you don't need as high a BL to lift them. I can't see any reason you would want to go the other way.



Not for any obvious reason. But if you want them to, just give Martians a -4 racial ST, which allows them to lift about the same objects on Mars humans could lift on Earth, without changing their mass from human normal. Problem solved.

I really think you are trying to scale the wrong thing if you are trying to keep Martians at ST 10.

Not at all; it's no stranger than running a Borrowers or Lilliput campaign and noirming little people ST to 10. For a Barsoom-like campaign where Earthmen are supposed to be at an unrealistic advantage, it's perfect.

[Bruno]

Originally Posted by isf

So it appears that the rules on B350, don't treat the differences between Mars/Terra and Terra/2.5G world as the same. Penalties for differeng gravity penalize the 2.5G native on Earth more than the Terran on Mars.

The greater absolute difference is important - it means the "mismatch" between the feeling of weight and the feeling of inertia 2.5G Man On Earth is feeling is MUCH bigger than 1G Man On Mars is dealing with.