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-   -   [Spaceships] getting into orbit without superscience? (https://forums.sjgames.com/showthread.php?t=174554)

Fred Brackin 08-28-2021 09:34 PM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by fdsa1234567890 (Post 2394284)
In a context in which metallic hydrogen is the main fuel source, might there still be applications for which chemical engines are preferred for safety reasons?
.

No chemical fuels are truly safe. Anything mixed with LOx is explosive. Hydrazine is deadly poisonous and fuel grade Hydrogen Peroxide is fantasticaly corossive. Then there are risks associated with cryogens you have to keep at 20 K or lower.

You probably fuel the maneuvering thrusters with some compressed gas.

Anthony 08-29-2021 01:25 AM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by Fred Brackin (Post 2394287)
No chemical fuels are truly safe.

While true, metallic hydrogen, being a monopropellant, would be quite capable of blowing up without any mixing (metallic hydrogen fuel is probably impossible, metallic hydrogen hasn't shown any signs of being metastable, but it's not proven impossible).

Prince Charon 08-29-2021 07:49 PM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by Anthony (Post 2394297)
While true, metallic hydrogen, being a monopropellant, would be quite capable of blowing up without any mixing (metallic hydrogen fuel is probably impossible, metallic hydrogen hasn't shown any signs of being metastable, but it's not proven impossible).

You know a story is going pretty far into rubber science when the hero's spacecraft is armoured in 'an alloy of hydrargyrum and metallic hydrogen.'

Phil Masters 08-30-2021 09:15 AM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by Prince Charon (Post 2394372)
You know a story is going pretty far into rubber science when the hero's spacecraft is armoured in 'an alloy of hydrargyrum and metallic hydrogen.'

That goes so far into crazy that I have to ask where it’s from.

Prince Charon 08-30-2021 10:21 PM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by Phil Masters (Post 2394411)
That goes so far into crazy that I have to ask where it’s from.

Not 100% certain. I think it was synthesized by my imagination mixing up other crazy things I read (I did need to go look up the old name for mercury to get the spelling right), but it might be from an old SF novel or short story I read long ago, as growing up I read a bunch that were written between 1930 and 1960 (thus, quite some time before I was born), and some that were older. I do think that I've read at least one story that used metallic hydrogen for something that it makes no sense to use metallic hydrogen for, and it may have been some sort of alloy.

Fred Brackin 08-30-2021 10:44 PM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by Prince Charon (Post 2394485)
. I do think that I've read at least one story that used metallic hydrogen for something that it makes no sense to use metallic hydrogen for, and it may have been some sort of alloy.

I don't doubt you but I don't believe it will have been in a truly old story. I don't think it's that old a concept. Though Wikipedia does put the first prediction of its' existence in 1935.

PTTG 08-31-2021 01:01 AM

Re: [Spaceships] getting into orbit without superscience?
 
Well, you have a lot of options for orbit without superscience... it's just that few are in Spaceships 1.

The most basic is to make a larger ship that's all fuel tanks and motors with the top third being the actual ship you want to get into space.

Then there's use of aerodynamic shapes, wings, ramjets and so on to provide the inital speed boost and then use rockets for the rest. I think stock SS has all the parts. You'll want the Ram Air Intake option for one of the more powerful drives.

Other options generally require infrastructure. For instance, you're going to want a space gun that can launch you into a suborbital trajectory where you can snag onto a skyhook to get you into space, or some other combination of those.

ericbsmith 08-31-2021 01:50 AM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by PTTG (Post 2394493)
Well, you have a lot of options for orbit without superscience... it's just that few are in Spaceships 1.

The most basic is to make a larger ship that's all fuel tanks and motors with the top third being the actual ship you want to get into space.

Then there's use of aerodynamic shapes, wings, ramjets and so on to provide the inital speed boost and then use rockets for the rest. I think stock SS has all the parts. You'll want the Ram Air Intake option for one of the more powerful drives.

Other options generally require infrastructure. For instance, you're going to want a space gun that can launch you into a suborbital trajectory where you can snag onto a skyhook to get you into space, or some other combination of those.

All of them require infrastructure. Having a booster rocket stage implies a large industrial base on the planet to make and maintain them. While flying into orbit can help, it's basically impossible with a single-stage-to-orbit model, so again you need launch ships to do the initial flying which requires ground support.

And that's the main issue with realistic spaceflight - you can't really have the tramp freighter full of PCs bouncing from backwater planet to backwater planet having fun adventures. Any planet with the industrial base to launch rockets is going to have the rocket industry dominated by large corporations.

scc 08-31-2021 01:57 AM

Re: [Spaceships] getting into orbit without superscience?
 
Your best bet is probably a combination of these two things:
1. A Spaceplane, probably two stage, with Sabre engines, costs to orbit may well drop below $10 per pound.

2. Did you every read the Coyote novels? Below borrow off of them, the setting isn't Earth, at least as we know it, but rather one of several habitable moons orbiting a gas giant, this makes it possible for you to play around with things by making the planet (moon) smaller and easier to get of, it also means there's greater economic incentives for space travel (Imagine what the European powers would have done for space travel if the moon promised to be a new Africa, one without the issue of pisky natives.)

RogerBW 08-31-2021 05:24 AM

Re: [Spaceships] getting into orbit without superscience?
 
Quote:

Originally Posted by ericbsmith (Post 2394494)
And that's the main issue with realistic spaceflight - you can't really have the tramp freighter full of PCs bouncing from backwater planet to backwater planet having fun adventures. Any planet with the industrial base to launch rockets is going to have the rocket industry dominated by large corporations.

And anything which changes that (like being able to drop a "rocket seed" nanotech package which builds a booster from local materials) will probably not support tramp freighters either.


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