[Space] The Galactic Empire according to GURPS Space

[David Johnston2]

Originally Posted by Fred Brackin

I only noted that you might need faster evolution and development to make up for 300 milion years less time. I didn't say it was even improbable.

Yet the farther "back" you go on a relative scale the more you're dealing with very simple organisms, just plain chemistry and thermodynamics. So the less wiggle room you have.

Waving your hands and claiming "Stuff simply hapened here 3 bilion years faster than it did on our world." is going to sound unlikely. Especially if it had to happen that way because their star was going to go red giant on them much earlier than our will. There'd be no way for the single-celled anerobic organisms to know that and prod each other to evolve faster.

A world where native life isn't past the microorganism stage is an extremely good candidate for relatively speed terraforming with the result being more habitable than a sophisticated biosphere.

[Fred Brackin]

Originally Posted by David Johnston2

A world where native life isn't past the microorganism stage is an extremely good candidate for relatively speed terraforming with the result being more habitable than a sophisticated biosphere.

Oh no doubt. That's sort of why I like that "appearance of O2" point as cut-off for non-Ancients style Terraforming.

The Ancients could seed some anerobic orgnaisms and come back in 500 million years but it's not so likely for humans.

[Rupert]

Originally Posted by Fred Brackin

Oh no doubt. That's sort of why I like that "appearance of O2" point as cut-off for non-Ancients style Terraforming.

The Ancients could seed some anerobic orgnaisms and come back in 500 million years but it's not so likely for humans.

Once a world has O2 and an atmosphere that's not ridiculously thin, humans can live on it in domes using about TL5 level technology (pumps and filters), and that makes it a lot more friendly an environment than space.

[Michael Thayne]

Since there was a complaint about jump points being in the middle of nowhere, I decided to figure out just what freight rates ought to be on the tech assumptions I've worked out. I came up with a design for a massive freighter designed to shrug off ~0.01c collisions with micrometeors. It's a TL11^ design built on an SM+14 unstreamlined hull—which, yes, makes several times larger than the largest container ships in existence today.

Front Hull
[1-6] Cargo Hold (300,000 tons cargo)

Central Hull
[1] Smaller Systems (three at SM+13): one Control Room (C11, comm/sensor 13, thirty control stations), one Habitat (394 cabins, four-bed automed sickbay, one gym, one office, 8,000 tons cargo), one Cargo Hold (15,000 tons cargo) ($1.6B)
[2-6] Cargo Hold (250,000 tons cargo)
[core] Light Force Screen (700 dDR) ($15B)

Rear Hull
[1] Standard Reactionless Engine (1G acceleration) ($1B)
[2-6] Cargo Hold (250,000 tons cargo)
[core] Fusion Reactor (two Power Points) ($10B)

It has artificial gravity and gravity compensators.

Total cost is $29.6B. A tanker version (replace all the cargo holds with fuel tanks) costs slightly more—$34.5B. Assuming that a ship costs 1.5% of cost to operate (including cost of financing), this yields a freight rate of about $100 per ton of freight per "run" between a garden world at 1 AU and a jump point at 4 AU. This is higher than the rate listed in Spaceships 2 for reactionless drive craft. I suspect those numbers assume a cheaper design without the force screen.

[cptbutton]

Originally Posted by AlexanderHowl

The problem is that the waste heat alone would probably kill everyone, even if you used fusion. The energy required to support a human being, from atmospheric recycling to food production to waste management, is around 1 MW per person (in the case of modern civilization, the vast majority of that energy comes in the form of sunlight, which drives the atmospheric, hydrologic, and photosynthetic cycles). A world with 1 trillion people would require around 1 EW of energy, over 7x as much as falls on the Earth, and the waste heat they generated would heat them up to the equivalent of Mercury.

While it doesn't invalidate your point, I recall it as there were 20 agricultural worlds which basically did nothing but grow food for Trantor. Which of course brings up the question of the waste heat from all those ships. Might be better to ship it all down by space elevator.

[Johnny1A.2]

Originally Posted by cptbutton

While it doesn't invalidate your point, I recall it as there were 20 agricultural worlds which basically did nothing but grow food for Trantor. Which of course brings up the question of the waste heat from all those ships. Might be better to ship it all down by space elevator.

This is a case where Asimov's romanticism got the better of his scientific thinking. The 20 agricultural worlds and their ships are the equivalent of the grain ships that kept food coming to Rome. They really don't make sense looked at unsentimentally.