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Old 07-13-2022, 07:10 PM   #31
Anthony
 
Join Date: Feb 2005
Location: Berkeley, CA
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Originally Posted by hal View Post
But, what if you can use a two stage rocket to accelerate towards the sun, separate at 40,000 km above the sun, and then use a mag sail away from the surface of the sun? The single stage vessel after separation would have 1/3 rd the original mass, gain free acceleration via mag sail, and perhaps gain more than the original +10 k/s boost given in Robert Zubrin's scenario?
Unfortunately, in this scenario you're actually moving faster than the solar wind for a significant chunk of your trip, making magsails counterproductive.
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Old 07-13-2022, 09:12 PM   #32
hal
 
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Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Originally Posted by Anthony View Post
Unfortunately, in this scenario you're actually moving faster than the solar wind for a significant chunk of your trip, making magsails counterproductive.
Sadly, so it would appear. Maybe the gravity assist model works for the plasma drive.
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Old 07-14-2022, 05:25 AM   #33
scc
 
Join Date: Mar 2013
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Originally Posted by Agemegos View Post
1) Because charged-particle beams diverge owing to electrostatic bloom, and there is no way to reduce the divergence analogous to using enormous objectives for laseer beams.

2) Because the magnetic field of the Sun exerts a Lorentz force on charged particles moving through it, perpendicular to the direction of movement of the particles, so as it varies the beam of charged particles will wander and swerve.
Ah, well #1 hadn't occurred to me for some reason. That said keep in mind that charged in this case is a somewhat loaded term, we only want the beam to beam charged to ensure that it interacts with the MagSail and it's the actual kinetic energy of that particles that propel the ship, so how charged the beam is is can be kept to a minimum to prevent these problems
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Old 07-14-2022, 09:13 AM   #34
Aldric
 
Join Date: Nov 2015
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

So, if you don't like the idea of pushing around a huge rock, the best alternative offered by Spaceships at TL10 seems to be:
19 fuel tanks for an Advanced Fusion Pulse Drive (an Antimatter Plasma Rocket would give more, but I don't think any level of fabricators you can carry on the ship coild refuel it). Cram everything else as smaller systems on your last slot (probably looking at 10 SM-2) systems compared to the ship.
That's 5700 mps (100x19x3) with 0.0005G per engine.
Not sure where that takes you.
Adding a Magsail somewhere gives another 375 mps, but the acceleration would only be 0.0001 per sail. But you could use that before turning on the fusion drive and to slown down at the end.
Values for the smaller systems taken from Spaceships 8, since that's where I found the numbers for engines and sails.

Ps: Mag sails can only take you to 375 mps at best, but can they still work and slow you down from much higher speeds? If that's the case you can use more than half of the delta-v from the fusion drive to accelerate, depending on how much time you're willing to spend to decelerate.
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Old 07-15-2022, 11:48 PM   #35
scc
 
Join Date: Mar 2013
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Originally Posted by Aldric View Post
So, if you don't like the idea of pushing around a huge rock, the best alternative offered by Spaceships at TL10 seems to be:
19 fuel tanks for an Advanced Fusion Pulse Drive (an Antimatter Plasma Rocket would give more, but I don't think any level of fabricators you can carry on the ship coild refuel it). Cram everything else as smaller systems on your last slot (probably looking at 10 SM-2) systems compared to the ship.
That's 5700 mps (100x19x3) with 0.0005G per engine.
Not sure where that takes you.
Adding a Magsail somewhere gives another 375 mps, but the acceleration would only be 0.0001 per sail. But you could use that before turning on the fusion drive and to slown down at the end.
Values for the smaller systems taken from Spaceships 8, since that's where I found the numbers for engines and sails.

Ps: Mag sails can only take you to 375 mps at best, but can they still work and slow you down from much higher speeds? If that's the case you can use more than half of the delta-v from the fusion drive to accelerate, depending on how much time you're willing to spend to decelerate.
So ignoring your idea of grabbing a rock (because it doesn't work, best it can get you is 3,420 mps).

So you can't make fuel for Fusion Pulse drives in the target system, but I think there's rules somewhere that say you can make fuel for Anti-matter drives, so that's what I'll use.

Now my plan is that these expeditions are launched with human crews, gene-engineered to be able to hibernate on the way to the destination systems under the assumption that something unexpected might come up (And it does, a portal into hyperspace is found in Alpha Centauri). Now a 100 year travel time to Centarui isn't too bad, if the crew is 30 when they launch they'll age 40 years in transit and 40 back under the plan, so they'll be 110-120 when they get back, which isn't too bad, but the further out you go the worse it gets, stars at the 10 ly mark will age the crew will age 200 years on the trip, and that won't work. Which means my only options are to increase the level of Hibernation beyond the Bio-Tech allowed limit of 4 or make the ships travel faster some how, and my thoughts are to do both, throwing strict realism out the window to get faster travel.

So current time-line for this game world:
2020: Discovery of a method of manufacturing reactionless drives. It has a number of limitations, most notably a very low top speed and a requirement to be manufactured in Zero-G, but it allows cheap and easy access to space and spurs the development of space industry.

2022: A Ukrainian, distort over the destruction of his homeland by the Russian invasion, crashes the under construction EuroVolt 1 power satellite into Moscow. Russia launches ICBM's in retaliation and the single squadron each of fighters and Europe and America have managed to re-engine over the past two years are diverted from a likely futile attempt to stop the colony drop to destroying the missiles, all pilots are lost as they are forced to take their fighters into the atmosphere at too high speeds to stop the strike.

In the wake of this the war is called in Ukraine's favor and the Outer Space Treaty is re-written, the sections preventing militarization have to be thrown out as unworkable. Provisions where also added preventing the construction of large objects in near-Earth space, prompting the construction of several colony spinners at L5 or L4 to provide housing for workers of various industrial projects (Power satellites and various Zero-G manufacturing mainly, but novelty stuff like 'Space Beer' also exists)

2030: Various factors, including the effects of Climate Change and internal political problems, disrupt things in the US and China to the point the two nations fall into outright civil war. The EU and CANZUK begin their ambitious terraforming programs, in part as a massive jobs programs. Human genetic engineering is pioneered, wealthy countries with good public health systems begin providing gene-cleaning programs to citizens in order to reduce costs.

2070: Manned interstellar missions, just barely possible, are launched with gene-engineered crews.

2190: Alpha Centarui mission discovers a whole into hyperspace and uses it to return.

2240: Alpha Centarui mission returns home early, taking only half the time it took on the way. Irrefutable proof of hyperspace sparks massive investment in research

2250: First colony flights launched to the stars.

2300: On an ecologically over stretched Earth, no longer able to support her massive population, things go to hell and governments start collapsing.
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Old 07-16-2022, 12:13 AM   #36
Fred Brackin
 
Join Date: Aug 2007
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Originally Posted by scc;2443370
[B
2022[/B]: A Ukrainian, distort over the destruction of his homeland by the Russian invasion,g.
Possibly you've been victimized by an autocorrect system. The Ukaranian would more likely be "distraught".

Farther down there's a "whole" into hyperspace.

If this was to become a campaign handout or similar document those teeny errors might be worth chasing.
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Old 07-16-2022, 06:03 AM   #37
scc
 
Join Date: Mar 2013
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

So that timeline could really do with some filling out, if anyone's got any idea, please let me know. And while adding the dates that various planetary stations (spinner colonies established to anchor operations for various planets) came online it doesn't really add anything to the setting.

And while I'll be pulling from some material from THS I won't be pulling a lot, I don't really have an interest in the chaotic and frequently alien Trans-humanism of the setting. Things also tend to exist for the sake of existing/to make the setting more interesting/just using a biological solution instead of an existing technological one. Some stuff also seems way too cheap common (looking at bioroids)

So I've got a good setup for a variety of Retrotech campaigns of High Frontier TL8 through TL10, with a side order of Military Sci-Fi in 2030 (call that emergent TL9 with power armor, always fun) but the bit that's really caught they eye at this point is the 2300 point. What happens here is that continued environmentally unsound practices remained in us through Africa, most of the America's, and Asia and these places, no longer able to support their existing populations have collapsed and waves of refugees have begun flooding areas that didn't behave irresponsibly, collapsing them in turn and the PC's are people who where working on one or more spinner colonies (and actually average people, like an electrician on a maintenance contract) most salvage from this mess what they can. Notably the colonies are something of a sausage fest, so women are high on that list, so one mission might see them getting a lot of the Victoria's Secret personal out, including the Angel's (The colonies didn't previously make their own clothes.)

So a big question for me here is how do I make templates for things like particle accelerator tech and power satellite builder and make them work for something close to an Action game?
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Old 07-16-2022, 07:49 AM   #38
Fred Brackin
 
Join Date: Aug 2007
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Originally Posted by scc View Post
/just using a biological solution instead of an existing technological one. Some stuff also seems way too cheap common (looking at bioroids)
Do away with bioroids all you want but don't discard the bio/nano solution to space radiation. Specifically the Radiation Regeneration nano TS introduces at TL10 (although the Immunity to cancer is nothing to sneeze at).

Without these things just pulling off an 18 month Mars mission without anyone dying from radiation is a major exercise. That's assuming mature TL9 radiation drugs too.

Even with the other TL10 anti-radiation tech you'd see humans restircted to big space stations and still getting expensive anti-cancer/anti-radiation treatmets every 10 to 20 years. People who do have these big heavily shielded space stations tend not to have your "Mars Needs Women!" problems too.
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Old 07-16-2022, 04:11 PM   #39
scc
 
Join Date: Mar 2013
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Originally Posted by Fred Brackin View Post
Do away with bioroids all you want but don't discard the bio/nano solution to space radiation. Specifically the Radiation Regeneration nano TS introduces at TL10 (although the Immunity to cancer is nothing to sneeze at).

Without these things just pulling off an 18 month Mars mission without anyone dying from radiation is a major exercise. That's assuming mature TL9 radiation drugs too.

Even with the other TL10 anti-radiation tech you'd see humans restircted to big space stations and still getting expensive anti-cancer/anti-radiation treatmets every 10 to 20 years. People who do have these big heavily shielded space stations tend not to have your "Mars Needs Women!" problems too.
Not too much of a problem. Cis-Luna habitat and manufacturing stations can be buried under 5 feet of rock. Ships are going to be getting around the system using Mag-Sail and once out of the boost phase those can be reconfigured to be radiation shields. So on your 18 month Mars mission only periods where you're on the surface are a concern and building storm shelters can be made a priority once landed. Missions to Jupiter can simply not enter the dangerous of the radiation belts. And so on, THS has that more to enable Neo-liberal or anarchist ideas and make things like artist communes possible, I'm not allowing that, mostly on the grounds of cost.
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Old 07-16-2022, 09:30 PM   #40
Fred Brackin
 
Join Date: Aug 2007
Default Re: [Spaceships] Getting A Few Thousand Extra MPS

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Not too much of a problem. Cis-Luna habitat and manufacturing stations can be buried under 5 feet of rock..
That's not enough against cosmic radiation. That divides all PFs by 100. You'd want 10 feet to give protection equal to Earth's atmosphere.

Generally PF schemes only delay when you need those expensive anti-radiation treatments.
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