GURPS New Space Opera Setting Idea

[Phantasm]

Originally Posted by Dammann

Exactly- I am trying to get as much input and as many viewpoints as possible before reinventing the wheel (and antigrav and reactionless thruster).

I think there's a Pyramid issue on e23 dedicated to space opera. Do you have that?

[Dammann]

Yep! I think I collected all the PDF Pyramid issues that I was certain dealt with science fiction or space, I've spent some significant time with the Winchell Chung's Atomic Rocket site and some time reading Luke's (?) page dealing with laser small arms and how to build death beams. I got Fractal World Explorer and Astrosynthesis and downloaded (forum user) Brett's excellent world/system builder worksheet. I have been statting up the ships from Ryan Wolfe's very cool Future Armada series, using GURPS: Spaceships, and started teaching myself Blender so that I can start making some 3d ship models and deckplans that directly suit my own needs and taste. I found some of my old Star Frontiers material from the 80s, to mine for adventure ideas.

I plan to run adventures in our galaxy, with realistically plotted star locations out to about 20 ly from Sol (as taken from the ISDB), and a fabric of sapient species that only know their immediate neighbors, at a wide range of TLs from stone age to TL12. I want to integrate as much GURPS material as I can, including the old GURPS Aliens species, the background from "Wild Life" from James Cambrias's GURPS Space Designer's Notes, and most of Ultra Tech. There are some GURPS Aliens I have decided I don't care for, but in a big galaxy with unknown stuff on the other side of Cidi space, there is room to change my mind. The thread about warfare conducted with UT RAW has been excellent reading!

I hadn't had anything to do with any rpg for about 15 years, and then the bug just bit me hard. My old core players are all over the country, so I have a group of six people willing to give this rpg thing a go.

[fredtheobviouspseudonym]

Originally Posted by lwcamp

Thus, allosaurs are roughly 5 to 7 feet tall.Luke

At the hip.

If they lean back and look around, they're going to be measurably taller.

I'll admit I'm not up on recent theories of dinosaur anatomy (or even if they're still called dinosaurs) but it's still pretty big. For comparison:

From Wikipedia: "An adult male Kodiak bear stands up to 1.5 m (5 ft) tall at the shoulder when it is standing on all four legs. When standing fully upright on its hind legs, a large male could reach a height of 3 m (10 ft).[3]"

From the Alaska Department of Fish and Game web site http://www.adfg.alaska.gov/index.cfm...wnbear.trivia: "Kodiak bears are the largest bears in the world. A large male can stand over 10' tall when on his hind legs, and 5' when on all four legs." [I'll assume Alaska Fish & Game has a pretty good handle on the facts in this case.]

So an Allosaur might nearly double it's height if it should choose to rear up.

And if it's head is only five to seven feet off the ground when it's fighting, why then all the better to bite you with, my dear.

[Johnny1A.2]

Originally Posted by tbrock1031

Erm, yeah, that is true. Any other names out there for the 20 lightyear radius around Sol?

Actually, I never determined what type of drive it was. I wanted a timeframe that was still long, but not hundreds or thousands of years long. It made my idea of an early sub-light interstellar war possible.

Can someone who's better at advanced math figure out what's necessary to pull this off? I had considered ramscoops for the acceleration and lightsails or magsails for deceleration, but the timeframes and speeds necessary elude me.

Depending on how realistic you want to be, this presents a nasty dilemma of physics. It's the energy involved. Here's a really oversimplified example:

Let's say your drive (however it works) lets your ship travel at .25c. That lets you get anywhere in your 20 light-year bubble in one long life-time, on a way way trip. You might be able to wage a war that way, if your combatants were really highly motivated.

Now let's say your starshp masses, oh, 100,000 tons, about the same as a big aircraft carrier in a modern wet navy. At .25c we can neglect th effects of relativity to a first approximation, so:

KE=1/2(m)(v^2)

I make the kinetic energy involved to be about 7.8 * 10^16 kW/h, if I didn't slip a decimal somewhere. Which doesn't mean much as a raw number. But think of it as:

* The full power output of Hoover Dam for not quite 5 million years.

* The equivalent of a 66 teraton explosion, or about 5 billion Hiroshimas.

* The same approximate power as the Dinosaur Killer impact.

* Very roughly 1000 times the combined power of the nuclear arsenals of the USA/USSR at the height of the Cold War (IIRC on the number of warheads).

That's one ship. One.

There are possible ways around this, but it's useful to give an idea of the scale of things here. If you want a war in space, what kind of war do you want? If this ship I just described hits an inhabited planet...well, somebody is going to have a Bad Day.

[Dammann]

I recommend reading up on the Venture Star, from Avatar. Here is the write up on Winchell Chung's Atomic Rockets. I was astonished that there was any good science in the movie, but then, you see it for a few minutes. The Venture Star presents a plausible way to get to the very nearest stars, without FTL.

One big problem with Space Opera is that anything becomes a deadly weapon if it is moving at a respectable fraction of lightspeed. It is a waste to build a warhead. Just get some really big rocks, ram them into your enemy at a significant fraction of light speed, and you win. If you have a FTL drive, you have a planet killing weapon. How do you have interstellar wars and other awesome things that are good in an rpg?

Here is a table of relative energy comparisons, again from Atomic Rockets. The significant part (for me) is that when you can get there, you can kill everything just as easily.

In my campaign, I am deciding that the real estate is too valuable to smash. I will assume that any civilization that goes around hitting life bearing planets with dino killer kinetic attacks gets everyone else to put aside their differences to put a stop to that civilization.

[Dammann]

When I say plausible, I really mean "plausible" of course.

[Phantasm]

Originally Posted by Johnny1A.2

Depending on how realistic you want to be, this presents a nasty dilemma of physics. It's the energy involved. Here's a really oversimplified example:
[snip]
There are possible ways around this, but it's useful to give an idea of the scale of things here. If you want a war in space, what kind of war do you want? If this ship I just described hits an inhabited planet...well, somebody is going to have a Bad Day.

I ultimately went with superscience lightspeed drives for most of that war (from Spaceships 7). It's also one of those things that happened "in the past" as far as the setting itself goes.

I've split the setting into a few other threads:

Racial Packages
Spacecraft
Combat Loadouts
Blastswords
and on the Roleplaying in General forum, a call for Ideas for Locations.

I've got more in MSWord .doc files than I've posted here to the forums.