Possibility: killing FTL via slowboat colonists

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Somes J
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

Destructionator wrote:That sounds pretty good.
Best thing I can think of is somebody setting off a high-yield nuke in one of the main habitats, maybe during a conference involving a lot of crucial technical people for maximum damage. Now we just need to come up with a group with plausible means and motivation for doing that.

Maybe the colonists were divided between a more luddite planetary faction and a less luddite space faction, and some elements of the planetary faction feared the space faction going the same way as whatever they were running away from in Sol, and sought to destroy them or force them to leave the system.
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Re: Possibility: killing FTL via slowboat colonists

Post by Destructionator »

That could work - it strikes me as a more in-character ending to nbsg too! I might just run with that. The problem is a big nuke might just knock out the whole cluster... will have to ponder.

I'm in the middle of a post about another topic though, so stay tuned.
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Re: Possibility: killing FTL via slowboat colonists

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Now, let's discuss the ASV Falcon accident. (Named for the Star Wars ship btw.) This has had two major versions:

Old - back when the setting was still soft sci-fi, this was brought on by battle damage. The First Interstellar War was a much bigger deal in the soft setup; it was between two great powers and involved ground war, space war, and planetary invasion leading to occupation.

There was a fleet engagement in the final push to take the planet, and several ships were taken out. The wrecks were left behind as the rest of the fleet continued to finish the job. One of them, left for dead and severely damaged at the battle scene, was the Falcon. But, they weren't quite dead.

With most the senior staff incapacitated and the ship a wreck, they had to make due with the junior officers alone and in command. The challenge: somehow let everyone else know they were still alive.

Things go to hell when an enemy heavy cruiser shows up. But, playing dead + a space fighter trick + the Picard Maneuver + a final bluff turns this around to their advantage, forcing the enemy ship to surrender needed parts to repair their radio kit. Rescue shows up shortly later and the survivors are evacuated and brought home.

The climax of suspense is when the enemy ship shows up.




New version - with the switch to hardness came a big change in the setting itself. Both powers were rewinded in time, with one of them being Earth of like 2015; no significant space warships, meaning no space war. And of course, the FTL drive was restricted to just the A'millians for a long time, so the ground war is completely different. It really isn't a war at all; scarcely a shot is fired.

They have three armed ships escorting a few transports, carrying the people they are evicting from the planet. (The armed ships are there just in case missiles open fire on the way back. They didn't.)

They would all go to the jump point and jump together. Problem is, one ship, the Falcon had a minor flaw in her jump drive. When they fired it up, it did an in-system jump and exploded with vigor, severely damaging the ship, and leaving her lost.

The challenge: figure out where they are, contact home, survive... and figure out a brilliant fix to get them home. It is more like Apollo 13 and I love it.

The climax of suspense is when they send a signal to ground control, and it takes several seconds for them to answer - all light speed lag.

End result is they are evacuated and brought home. Everyone makes it, except the ship itself, which is left behind in its strange orbit.





But, now we don't have FTL, so it blowing up is no longer an option. But I don't want to lose the story. How to salvage it?

Well, it occurred to me today that I might be able to go back to the old way, sort of. A space civilization would more plausibly have a way to fight back, so maybe there is a battle.

Though, I'm not happy with a battle. It is too brutal for my likes now. I won't write it off, but I'm not excited about it.

How about a micrometeor? This could act like the exploding FTL drive, without needing a FTL drive. One change is there can't be the fun ribbing between the crew and the drive engineer, but that's ok. Two problems though: it wouldn't likely cause as sudden and serious damage as the exploding drive (shittons of energy were poured into them from the misjump, causing them to turn to plasma, blasting the coil casing at high speed into the fuel tanks, along their whole length. They quickly depressurized, giving the ship a hell of a torque in the process.).

Perhaps it could a spray of rocks hitting them, but what are the odds of that? If you get into a bigger rock, then it is just carelessness on the part of the crew and controllers for it to hit. They should have seen it and avoided it. So it has to be something small and fairly unpredictable to avoid incompetence. (The idea is to show the engineers being brilliant, not blind!)

The other problem is it takes that suspenseful second ticking away. When impacted, the ship's inertia will keep it going... hell, it'll stay right with the convoy even. They'll never really be alone, and they'll always know right where they are.

gah, I hadn't thought of inertia until now. That ruins just about everything.



So asking for ideas. Here's the criteria for an optimal solution:

a) It causes severe damage to the ship, preferably keeping the sudden big spin in the first several seconds.
b) They shouldn't stay in formation; the ship should be alone out there
c) The rescue should take awesome brainpower from both ground control and the crew
d) It would be cool if they could still be lost, so those first few days remain mysterious and perhaps hopeless
e) They should be on their own for weeks or months, to drive the supplies to their limit (and give enough time for the crew to get to know each other). We can move the human colony around to tweak travel time. I'm still undecided on specifically where they are anyway. I'm leaning toward solar orbit in the inner system though, not that far out from where the planet is.




Here's the model I made of the ship to get it into your brain:
http://arsdnet.net/sc01-1.jpg
http://arsdnet.net/sc01-2.jpg
http://arsdnet.net/sc01-3.jpg
http://arsdnet.net/sc01-4.jpg

The rectangles on the outside are the FTL drive. The big cylinders are the propellant tanks; either hydrogen or oxygen. The sphere in the front is the crew section. The engines in the back are nuclear thermal drives, two independent sets. They each have fission reactors built in that run to provide electricity for the ship, and the waste heat propels it.

The ship provides no artificial gravity and has a crew of seven.


When the drive blew, one of the four warp prisms got almost all the energy and blew through one of the propellant tanks entirely, and damaged the plumbing in one of the engines. It did no serious damage to the (armored) crew section.



All this is flexible, but I really like how the new way turned out, so staying close to it would be nice. The FTL's misjump worked so well for it... it is almost as if I designed it specifically for this task!
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Re: Possibility: killing FTL via slowboat colonists

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Destructionator wrote:That could work - it strikes me as a more in-character ending to nbsg too!
That would indeed have been a much more plausible ending to nBSG than what we actually got.
I might just run with that. The problem is a big nuke might just knock out the whole cluster... will have to ponder.
I was sort of envisioning the explosion maybe blowing a giant hole in the habitat and leaving the air to all be instantly sucked out in a short-lived jet. If the habitat's builders were cautious a lot of individual buildings (maybe all significant ones) would have independent life support systems in case of a catastrophic atmosphere loss, but I was envisioning the bomb planted directly under or right next to the building where this conference was being held, so it would still result in a devastating loss of skilled manpower.

I sort of have a mental image of one end of the cylinder being blown open by the nuke, sort of like this:

Image

Habitats facing away from the blown-apart end would be at least partially shielded by the habitat and should be OK. Habitats on that end might suffer damage from the shrapnel, and possibly radiation effects from the bomb if they're close enough. The destroyed habitat itself might be salvageable.
Destructionator wrote:But, now we don't have FTL, so it blowing up is no longer an option. But I don't want to lose the story. How to salvage it?
What about having a catastrophic failure of the reactor or the rocket? Rockets strike me as something that could plausibly have some rather catastrophic failure modes, and an internal mechanical problem just feels more plausible to me than being struck by a meteorite (a spacecraft is generally a pretty small target for meteorites).
The other problem is it takes that suspenseful second ticking away. When impacted, the ship's inertia will keep it going... hell, it'll stay right with the convoy even. They'll never really be alone, and they'll always know right where they are.

gah, I hadn't thought of inertia until now. That ruins just about everything.
Maybe they're on a collision course with some sort of object. One possibility that occurs to me is they were going to do an aerobraking manuever combined with conventional braking (by turning around and firing their rockets). Only now their engines don't work, so instead they'll hit the planet at too high a velocity and/or the wrong angle and crash into it or burn up in the atmosphere.

Only thing is if they're in a group they should be able to piggyback off the other ships, unless maybe the propellant margins are too thin. Easiest way around that would be to say they were on a solo mission. Preferably the planet they're aerobraking at has no settlements nearby, or just a few small outposts, so there's little or no local help available.

From the sound of it, this might work better as an exploration mission to an outer gas giant that suffered a catastrophic engine failure.

Yes, I think that would work nicely. An exploration mission to an outer gas giant. They're going to use aerobraking in the gas giant's atmosphere to save fuel so they can minimize trip time. The drive or reactor suffers a catastrophic failure. Maybe have it be a nuclear thermal rocket of some kind; the reactor is the heating element for the drive, to turn it from reactor to drive you switch from an internal coolant-radiator loop to expelled coolant, and the reactor would be running constantly so it could have a violent failure of some sort while still weeks or months out from the gas giant. The ship will still arrive at the gas giant, but too fast, so it will burn up like a meteor in the gas giant's atmosphere. They've got weeks to do nothing but sit there, all alone, with only mission control hours away by radio to help them, knowing that if they don't find a way to slow themselves down they're doomed.

Hmm, how would they get out of it? Hmm, maybe they could jury-rig a solar moth and use it to heat the propellant they've still got in their tanks. It might need big mirrors to work very well in the outer system, but maybe it could be done. Alternately, it might be easier if the mission is instead to a warm or hot Jupiter of a companion star orbiting the Amillian sun at, say, 30 AU. The alien hostility of a hot Jupiter environment kind of appeals to me for a story like this. Ooh, ooh, for a mission to a hot Jupiter of a companion star a makeshift solar sail is also an option, since they'd be heading toward the sun, instead of away from it as they would be if they were headed for an outer gas giant.
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Re: Possibility: killing FTL via slowboat colonists

Post by Destructionator »

Hmm. Let's see about defining the solar system.

A little back detail is the inhabited planet is the second in the solar system; I'm not sure if I've used this anywhere, so it could always change.

Anyway, let's run with a binary star system. Let's say we take our own solar system, and add Wolf 359 out 30 AW away (that's the orbit of Neptune btw). How bright would it be?

I did some rough calculations. 30 AU is 30x farther from us than the sun, of course (on average). Light does inverse square, so it is 1/900 its full brightness. Wolf 359 has .001 the luminosity of the sun, so we divide that through too.

In total, the other star would be 1/900000 the brightness of the sun. log base 2.512 of 900,000 is ~ 14.9. That's the difference in apparent magnitude of the sun and the dwarf star.

The sun has a magnitude of -26.74. Add 14.9 to get -11.8 for the apparent magnitude of the companion star. How bright is that?

Well, the magnitude of the full moon is -12.7. So we're about 1 dimmer; 2.5x difference in brightness. I'd put it at about the brightness of a half moon then. That's something we can relate to.


How big will this star be? Radius of wolf 359 is .16 that of the sun. I don't think it would be inverse-square for distance, but rather trigonometry, but it certainly will be smaller than the absolute ratio anyway. So I'm imagining it would be a very bright single point in the sky; that half moon smushed down. It'll be there most of the year, but sometimes it will be visible during the day, and other times, during the night. As the year goes on, it will gradually change - just like Jupiter in the real world. (All the outer planets really, but Jupiter is one you can easily follow with the naked eye, yay).


What about solar energy flux? Goes back to the luminosity ratio: it'll use that same 1/900000 ratio. 1.4 kW / m^2 is the sun at Earth. Divide that by 900000 and we get about a milliwatt per square meter - negligible. (Obviously; you wouldn't try to run solar panels off a half moon either.)

So I'm not concerned about environmental changes either. Meaning.... we could drop this companion star right in there!

One more thing though: what about gravity? Does this significantly move the center of mass of the system? Will is screw up spaceflights?

The mass of Wolf 359 is 1/10 that of the sun. It's gravity on Earth would thus be 1/9000th that of the sun at this distance... that's about 3x the effect Jupiter has on us, which is already very small. I want to do a simulation though to see what happens with outer planets and comets; will be interesting to see a diagram of where ice would melt too.




But yeah, this looks pretty workable. Replace Neptune with Wolf 359. Then put Neptune back as our hot jupiter! It might be very close to the red dwarf, so it would indeed be hot.

I think I like it so far.
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Re: Possibility: killing FTL via slowboat colonists

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What would the star look like from an orbital habitat? I could see it being moderately annoying there. At night, it'd be visible same as on the planet (though perhaps less often during the year), but the habitat rotates at a much higher RPM than the planet.

Imagine the half moon "streaking" across the sky every two minutes. Might be a bit annoying, but probably not a big deal.


That's one thing I find sad about the view out of a habitat though: everything rotates, so you can't dwell on any one thing.

This is counter acted by the easy access to space they provide.
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Re: Possibility: killing FTL via slowboat colonists

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Destructionator wrote:The mass of Wolf 359 is 1/10 that of the sun. It's gravity on Earth would thus be 1/9000th that of the sun at this distance... that's about 3x the effect Jupiter has on us, which is already very small. I want to do a simulation though to see what happens with outer planets and comets; will be interesting to see a diagram of where ice would melt too.
I think the simplified rule of thumb is you can have stable orbits up to 1/5 the distance between the companion stars at closest approach. So if the closest approach was 30 AU you could get stable orbits up to 6 AU; big enough to contain Jupiter and everything inside its orbit. I imagine beyond this you'd probably have a large cleared zone, and then maybe a distant cometary halo that orbits both stars. That might be for equal mass stars though, in which case the planet-forming zone would presumably be bigger for the Amillian sun and smaller for the red dwarf.

This works out nicely, as you still have room for the gas giant you wanted.

Incidentally, binary stars tend to have pretty eccentric orbits so if the closest approach is 30 AU the companion star will probably be quite a bit farther away for most of system's revolution. You probably can't make the closest approach much closer than 25 AU and still have room for the gas giant, unless you make the Amillian sun significantly dimmer than Sol (moving the snow and tar lines inward).

--------

Incidentally, here's a little issue to consider: does Amillia have a stabilizing satellite?

Recently I've been doing some work on my own uni on an ancient race that terraformed a vast number of planets throughout the Local Group, thus explaining why Earthlike planets are much more common in my uni than they probably realistically will be (since it's hard SF and I want a sort of space opera feel it really helps to have lots of habitable worlds close to Sol). One of the long-term issues with terraforming is a large satellite to keep the axis from wobbling and keep the climate stable - most planets you'd be working with probably won't have a moon like Earth, and it seems to be one of the crucial factors in making a planet friendly to complex life (imagine if the planet flopped on its side like Uranus every few tens of millions of years - that'll really mess up your carefully crafted garden world!). If you want long term stability you want to move a suitable body into orbit of your planet. I think it can be done - if you have Von Neumanns to cover half of a suitable jovian sattelite with rockets and strip its ice layers for reaction mass! But for a group with more modest tech, well, it'd be ... interesting.

If you don't have Von Neumanns the only option might be not to bother, or to leave it off until you have a massive solar system spanning civilization. The pole swings take many thousands of years, so in the short term it probably wouldn't be a serious issue. It might also be easier to set up some sort of mirror and sunshade system to control the climate over the long term than to bring in a moon - I didn't use that because I wanted a system that could last into geologic time without maintenance, so humans could find lots of long-abandoned terraformed worlds with ecologies that had been evolving divergently for hundreds of millions of years.

Might be an interesting issue to touch on for the future - the Amillians might have some sort of long-term plan to move a moon into orbit of their world to stabilize the terraforming, or set up some sort of massive mirror and sunshade system. Or move everyone into habitats.

Just another reason habitats make more sense than terraforming. ;)
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Re: Possibility: killing FTL via slowboat colonists

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Somes J wrote:I think the simplified rule of thumb is you can have stable orbits up to 1/5 the distance between the companion stars at closest approach. So if the closest approach was 30 AU you could get stable orbits up to 6 AU; big enough to contain Jupiter and everything inside its orbit. I imagine beyond this you'd probably have a large cleared zone, and then maybe a distant cometary halo that orbits both stars. That might be for equal mass stars though, in which case the planet-forming zone would presumably be bigger for the Amillian sun and smaller for the red dwarf.
Indeed. Something else here is the outer star clears things out - but would it have affected planetary formation? I'm hoping yes - it might prevent asteroids from coalescing into planets, thus leaving multiple asteroid belts to mine!

A downside to that would be asteroid bombardment of the planet, but if we're going with terraforming and colonization, that's not a big deal anyway; life needn't survive long there naturally. A million years between asteroid impacts is enough time to get a colony going. (And hopefully, get it cool enough naturally so the terraformers don't have to deal with that. Should be fine anyway.)

Asteroid impacts don't scare the colonists much, due to the timeframes involved, and the confidence that they can handle it. This might be part of a reason why some people stayed in space: those guys would not only be immune to asteroid impacts (habitats can just move out of the way), but they could also protect the planet from them with relative ease.
This works out nicely, as you still have room for the gas giant you wanted.
I'm liking this star system...
Incidentally, binary stars tend to have pretty eccentric orbits so if the closest approach is 30 AU the companion star will probably be quite a bit farther away for most of system's revolution. You probably can't make the closest approach much closer than 25 AU and still have room for the gas giant, unless you make the Amillian sun significantly dimmer than Sol (moving the snow and tar lines inward).
I'm thinking I'll keep the sun very similar to sol itself (this is one reason why the conservative 'luddites' find it attractive - it is very similar to home sweet home).

Eccentricity is ok, maybe put it on an orbit similar to Pluto - 30 AU on its near approach, and 50 AU on the far. Pluto has an orbital period of ~250 years, meaning it's distance would pulsate just about with the century. (Remember how Pluto used to be the eighth planet?! Good times, good times.)

It'd be quite dim when on the far part of its orbit, giving amateur astronomers something to chew on in the olden days, and providing a bit of uniqueness to the environment. I like it.


This also goes back to the asteroid and comet thing. On the aphelion, it might yank fun in from the Oort cloud or Kuiper belt. Space colonists would like this because it shoots in a nice stream of water to the inner system for them, without having to burn out there themselves.


As an aside, it seems to be to be a good idea to use your kinetic energy before you slow down, when entering the system, to knock some of those outer system objects in toward where you intend to be. I'm not exactly sure how to do this - maybe launching missiles? That seems like it would shatter the object instead of changing its orbit, but whatever, any way it is done, it just seems like a waste to decelerate and lose all that energy when you can do so much with it.

Maybe decelerating your ship could accelerate little sailbots into a retrograde orbit in the outer system... hmm... then those sailbots could collide with objects on demand and send them in toward your colony. I wonder if it'd be worth the cost. It sounds cool to me.


Come to think of it, this isn't an original idea. Isaac Kuo on the sfconsim-l yahoo group proposed something similar a few months ago; in fact, I think I'm outright ripping him off here, but not quite sure (I read quite a few ideas over time and they blend with my own forming a synthesis blob in my brain. I then forget all the sources over time, and sometimes forget the underlying assumptions, leading to me sometimes being pigheadedly wrong). But I'll have to look up his emails later and see just what he had in mind.
Incidentally, here's a little issue to consider: does Amillia have a stabilizing satellite?
Yes, it is remarkably similar to our own moon, and has a long history of out of universe things.


In the earliest revisions, when the setting was outright fantasy (not even soft sci fi yet!), their star system was just our's, but in a kind of magical mirror universe. Once you cross through, you start living under the new rules of life, but the setting is otherwise the same. So same Earth, same moon, but the universe had all kinds of magic changing the development of civilization. One of them was a magical teleportation gate up to the moon! (I'm tempted to revive the fantasy iteration here. I had some cool stuff stuck in there, and I really liked the magic system.)

The next iteration was closer to what it had recently. I integrated the universes and shuffled around some of the other planets in the system, but I kept the planet mostly the same. Virtually identical to Earth, still has the moon. Difference here is the moon was no longer populated, but still physically the same. There was no explanation for this; God did it, accept it and move on.

The final iteration included changing the world map around and condensing the amillian civilization geographically in the world, leaving most of it unexplored; the surface changed a lot, but the same physical makeup was still the same as the oldest times: just like Earth and our moon.



I'm still running with that final iteration, but now have a more satisfying explanation than "god did it", in two parts: a) The system is a lot like home, so it is attractive to the conservative folks in the story. Out of the thousands of stars they surveyed, they picked the one that was closest to home. So a sun like star, an earth like planet, and a familiar moon around it. Then b) the terraformers did the rest of the intelligent design / natural evolution (importing Earth life). They nudged what they had the rest of the way to being like home.

Would this make it a popular destination? Well, sort of - two independent expeditions picked it. But more than that? Oh, I doubt it. An advanced civilization wouldn't have a need for a system that looks like the cradle. A closer star is easier to get to, and other star classes may have big advantages for a pure space civilization; hot Jupiters around bigger stars in particular look very cool to high tech space civs, with easy solar power and metals all in space, and lots of gravity assist potential. The hot jupiter here might be somewhat attractive, but not as much as a closer, bigger one.

This system is only uniquely attractive to a very, very small minority of people in the far future of Earth. Enough to have some fun with it, but not so much as to make it hotly contested :)


But yeah, short answer is it does have a large, stabilizing moon. The other star knocking a dwarf planet in and it being captured might be how it got there - this would be revealed in geology surveys; maybe their lunar soil is quite different than our own moon. But however it got there, it was already close to home when the people decided to go there.

One of the long-term issues with terraforming is a large satellite to keep the axis from wobbling and keep the climate stable - most planets you'd be working with probably won't have a moon like Earth, and it seems to be one of the crucial factors in making a planet friendly to complex life (imagine if the planet flopped on its side like Uranus every few tens of millions of years - that'll really mess up your carefully crafted garden world!).
I haven't really researched this, but would that really be a dealbreaker? It'd have some climate changes, as the poles are now getting direct sunlight, but middle latitudes - like where Europe is - might just work out without catastrophic changes. Life can survive there and expand back to fill in the voided areas.

Or, since it is probably a pretty gradual change anyway, life could always adapt / migrate without having outright extinction events in those areas. (Technological civilizations could handle it even more easily, through migration or staying indoors.)

But like I said, I haven't researched it, this is just a gut feeling.
If you want long term stability you want to move a suitable body into orbit of your planet. I think it can be done - if you have Von Neumanns to cover half of a suitable jovian sattelite with rockets and strip its ice layers for reaction mass! But for a group with more modest tech, well, it'd be ... interesting.
If you have the time to spend on it, a mass driver could do the job... if you have a loooong time to spend.

A problem with a mass driver would be gravitational drag would really hurt the exhaust velocity. As long as the mass is accelerated up to escape velocity, it will accelerate the body, but only by how much it exceeds escape velocity. Anything under that would be lost as gravity's constant tug reclaims the speed. Man, a big move would have to blow off a huge mass of the body, since this means poor specific impulse... not really attractive there either, but it could be done in theory.

Hey, speaking of gravity tugs, that's another method that might work, avoiding the loss under escape velocity too. Again though, it'd burn through a lot of reaction mass (big asteroid... hey, how would you get a big enough gravity tug in position in the first place? Gah, this might be a chicken/egg situation). And, even if it does work, it'd take a looooooooooong fucking time to do the job.


Attaching millions of magical fusion torches would be a much nicer alternative.
The pole swings take many thousands of years, so in the short term it probably wouldn't be a serious issue. It might also be easier to set up some sort of mirror and sunshade system to control the climate over the long term than to bring in a moon - I didn't use that because I wanted a system that could last into geologic time without maintenance, so humans could find lots of long-abandoned terraformed worlds with ecologies that had been evolving divergently for hundreds of millions of years.
Yea, you can always handwave exactly how they did it. Maybe throw a bone to the reaction mass thing by saying "hey wasn't there a Mars here at some point?" :P (alternatively, "man this moon is strangely like the naked core of a planet...")
Might be an interesting issue to touch on for the future - the Amillians might have some sort of long-term plan to move a moon into orbit of their world to stabilize the terraforming, or set up some sort of massive mirror and sunshade system. Or move everyone into habitats.
Coincidentally, they do set up some small mirrors, and most everyones indeed move into habitats near the end. But not for physical reasons. The little mirrors are to improve the efficiency of agriculture on the ground, letting farms in the north grow stuff from the equator and get bigger yields*, and they end up going to habs after a biological weapon slashes the population way way down**.

* I'm not sure if I'll keep the superfarms around. They are a cool application of space tech to the ground, but it isn't really necessary for them. There's plenty of usable farmland around anyway, and shipping stuff in is no big deal. But it is cool anyway!

** The "A'millian holocaust" I'm mentioned a few times scattered around. It cuts their population down to ~15,000. They manage to stabilize the situation, but realize that it can't work long term. They'd be very dependent on the human space colonies to maintain their status, who are willing to help, but figure they might as well just go up there and integrate completely.

The last scene to this part of the saga is mr and mrs author insert, the only two to stay behind at their old home, hitting the launch button for the last group of people to go into space, which includes their grand daughter. They they walk off alone to the empty world.


Anyway, mirrors and shades were used in the old iteration on Earth too - they were used to stabilize the climate while global warming greenhouse gas problems were fixed up. (I'm going to miss that whole section, now that Earth is out. There were lots of cool tech fixes I worked in there to fix up the peak oil and global warming stuff, and some heartwarming moments of cooperation... and of course, some tough love at times. Yay orbital bombardment!)
Just another reason habitats make more sense than terraforming. ;)
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

Huh, my last post didn't go through for some reason.
Destructionator wrote:Indeed. Something else here is the outer star clears things out - but would it have affected planetary formation? I'm hoping yes - it might prevent asteroids from coalescing into planets, thus leaving multiple asteroid belts to mine!
It seems reasonable to think that, as with Jupiter, there might be a gravitationally disrupted zone where an asteroid belt would exist. Given that the system already has a jovian planet, perhaps there would be two asteroids, a drier one similar to ours on the inside of the jovian's orbit and an icier one on the outside. The red dwarf might have its own icy outer asteroid belt as well. A solar system with three asteroid belts should give plenty of free-floating debris to exploit.

If we go with this model, there might also be a small outer gas giant or volatile-rich superterrestrial planet that had its growth stunted in the same ways Mars might have by Jupiter (compared to Earth and Venus Mars is conspicuously tiny). Although if the gas giant is at 5 AU like Jupiter I'm not sure there'd be room for it and an outer asteroid belt; the 1/5 rule leaves the edge of stable orbits at 6 AU. A safer bet if you want to go with that might be to either move the companion star out a bit (maybe give it a perigee at 40 AU instead of 30), move the jovian inward (and maybe make the sun a bit dimmer than Sol to eliminate any potential issues with that), or a combination of both.
Eccentricity is ok, maybe put it on an orbit similar to Pluto - 30 AU on its near approach, and 50 AU on the far. Pluto has an orbital period of ~250 years, meaning it's distance would pulsate just about with the century. (Remember how Pluto used to be the eighth planet?! Good times, good times.)
Hmm, Alpha Centauri A and B have a seperation that varies between 11.4 and 36 AU, so this may be a little on the mild side of eccentricity for companion stars (then again maybe not, I'm honestly too lazy to investigate the subject in any detail right now). Maybe make the seperation 30-60 AU to be safe, that shouldn't change things too much.
This also goes back to the asteroid and comet thing. On the aphelion, it might yank fun in from the Oort cloud or Kuiper belt. Space colonists would like this because it shoots in a nice stream of water to the inner system for them, without having to burn out there themselves.
I'd think the gravitational forces of the binary should be quite efficient at clearing a nice big hole in the comet halo, so aside from long period comets that have been kicked onto unstable orbits by other forces there probably wouldn't be much left for them to disturb by now, unless the system is very young. I could be wrong about that though.
This system is only uniquely attractive to a very, very small minority of people in the far future of Earth. Enough to have some fun with it, but not so much as to make it hotly contested :)
Sounds good to me. And even if other factions did follow, they might prefer to live in the Kuiper Belt or Oort Cloud, where they would be difficult to observe. Even if this isn't actually true in-universe it would make for a nice "conspiracy theory" type thing you could insert into a story at some point. Given the wider context of the setting, I could easily see there being equivalents to modern UFO nuts, and they'd arguably be more credible than modern Earth's version given these people know there's an advanced civilization that can build starships out there, or at least there used to be (I wonder how much they'd know about the rest of human/terragen civilization through astronomy and direct communication via radio or laser).
But yeah, short answer is it does have a large, stabilizing moon. The other star knocking a dwarf planet in and it being captured might be how it got there - this would be revealed in geology surveys; maybe their lunar soil is quite different than our own moon.
Isn't it pretty hard to get a capture of a large body like that, since something needs to brake it? Maybe it had a grazing collision with the Amillian homeworld and was captured that way. A captured moon implies the initial orbit would probably have been elleptical, I wonder what effects that would have.
I haven't really researched this, but would that really be a dealbreaker? It'd have some climate changes, as the poles are now getting direct sunlight, but middle latitudes - like where Europe is - might just work out without catastrophic changes. Life can survive there and expand back to fill in the voided areas.
I imagine complex life probably could survive, especially if introduced artificially instead of having to actually evolve there, but conditions like that would definitely make the planet less friendly to it.
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Re: Possibility: killing FTL via slowboat colonists

Post by Destructionator »

So I wrote a simulation and am now pissing away the work day playing with it. The eccentricity math is wrong, so I'm using circular orbits for now.

Yeah, if the outer star crosses the orbit of a planet orbiting the inner star, that planet is bound to get ejected eventually.

The inner star is affected by the outer star's pull (obviously), but I mean it visibly moves in the simulation. However, if I adjust the perspective to always follow the inner star, everything appears stable. So relative to the solar system, it doesn't break anything.

I added the hot jupiter at 0.3 AU out of the red dwarf, and it got a stable orbit using an orbital speed of about 18 km / s around the other star. That makes for a cool total delta-v....


So I tried to launch a space probe for it and screwed it up. Check out this plot:

http://arsdnet.net/spaceship.png

Yellow is the sun.
Blue is Earth.
Green is Jupiter.
Red is the red dwarf.
Teal is the hot jupiter.

(They orbit very closely together, so their paths mix.)


White is my probe's path...

Well, it sure saw the sights. Then eventually fell into the sun, where the calculations are not reliable (it showed it being ejected from the system, but it divided by zero to get that result...)
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Re: Possibility: killing FTL via slowboat colonists

Post by Destructionator »

Uranus is unstable. Take a look at it here (purple path):

http://arsdnet.net/uranus.png

The fun starts on the right, where the line just begins.

The dwarf lags behind it, tugging constantly with its gravity. This bleeds off Uranus' orbital speed, lowering its perihelion down to pretty damn close to Earth's path, keeping pretty close to the same aphelion.

This orbit continues until the dwarf catches up to it. Now, it pulls Uranus up and forward, giving it some of its speed back. It is now into its higher orbit, the big purple ring that crosses inside Jupiter (the green line) for a while.

This keeps up for about one more revolution of the dwarf star. Now comes the end of our planet's life.

This is what happened at the bottom of the image, where it is pulled down to cross the dwarf's orbit. The red star pulls it out, and then it is outside the star's orbit, and the dwarf takes the lead. At this point, we see the opposite of what happened at the beginning: with the star leading the planet, it gives the planet more and more speed.

More speed at apsis raises your periapsis... this is what is leading to the ejection.

Near the left of the image, we see the next effect. An object in an outer orbit moves more slowly than one inside. This means the star overtakes it, and we go back to the beginning; bleeding speed off.

Uranus goes through one half orbit of the dwarf star... which inverts its speed, turning it around on a slingshot.

Poor planet now has too much speed to stay in the system. Both stars start pulling it in, but it is going too fast. Uranus exits the system at the bottom right of the image, never to return. This took around 1000 years of Earth time, but that's nothing for the solar system.

:-(

:-(
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Re: Possibility: killing FTL via slowboat colonists

Post by Destructionator »

Well, I added the other planets, and only Uranus is doomed. With Saturn there, it gets ejected even faster than before. But the other planets are all OK.

Saturn is ~ 10 AU out, and looks stable here. So for this small star, it looks like we go to more like 1/3 the distance from the companion, maybe more.

That ratio must depend on the companion's mass.
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Re: Possibility: killing FTL via slowboat colonists

Post by Destructionator »

Somes J wrote:If we go with this model, there might also be a small outer gas giant or volatile-rich superterrestrial planet that had its growth stunted in the same ways Mars might have by Jupiter (compared to Earth and Venus Mars is conspicuously tiny). Although if the gas giant is at 5 AU like Jupiter I'm not sure there'd be room for it and an outer asteroid belt; the 1/5 rule leaves the edge of stable orbits at 6 AU. A safer bet if you want to go with that might be to either move the companion star out a bit (maybe give it a perigee at 40 AU instead of 30), move the jovian inward (and maybe make the sun a bit dimmer than Sol to eliminate any potential issues with that), or a combination of both.
My simulation says Saturn will be ok, so we should be pretty good here anyway. I might tweak things for fun, but since the dwarf star is so much smaller than the central one, it certainly gives more flexibility than a more even match in mass.
I'd think the gravitational forces of the binary should be quite efficient at clearing a nice big hole in the comet halo, so aside from long period comets that have been kicked onto unstable orbits by other forces there probably wouldn't be much left for them to disturb by now, unless the system is very young. I could be wrong about that though.
Yeah, the simulation seems to agree with you. I added in a bunch of random comets to the inner area and they were all very quickly cleared out by the outer star. Actually, my program has the dwarf star clearing out a huge volume of space. But, it only runs for a few thousand years, has imperfect precision (the more precise it runs, the slower it is...), and a handful of objects (double the number of objects = halve the speed of the program. And this is ignoring the gravity of anything smaller than Mars! If you count them too, it scales with the square of the number of objects. Much, much too slow for this. I don't have a supercomputer.)

But, given its inaccuracy, it still looks like that star will clear out a lot of space. That far from the real sun, the little star's gravity has a big effect, so I'm starting to feel that anything not orbiting the little star is going to be ejected. Or, if you go far enough out, then things might orbit stable again... if they are far enough out that they can treat the whole binary star system as a single point.


See what I saw: the comets I tested sprayed all over the solar system and take thousands of years to be ejected: http://arsdnet.net/comets.png The white lines are all comets that originated in circular orbits at 60 AU.
Sounds good to me. And even if other factions did follow, they might prefer to live in the Kuiper Belt or Oort Cloud, where they would be difficult to observe.
If they want to use fusion plants, this would indeed work. Probably lots of stuff to grab out there. But given the result I'm seeing so far, it'll have to be too far away from the stars to use solar power, which would make it pretty unattractive to most travelers.
Even if this isn't actually true in-universe it would make for a nice "conspiracy theory" type thing you could insert into a story at some point. Given the wider context of the setting, I could easily see there being equivalents to modern UFO nuts, and they'd arguably be more credible than modern Earth's version given these people know there's an advanced civilization that can build starships out there, or at least there used to be
Hehehe. "The Earthers are out there.... somewhere."

"Look! That streak must be a fusion torch... the Sol AIs have come to 'upgrade' us..."
(I wonder how much they'd know about the rest of human/terragen civilization through astronomy and direct communication via radio or laser).
It might not be very much at all. If they left the star system to be free of Earth/Sol influence, they might deliberately not listen. All they'd probably see through telescopes is a growing infrared radiation, as the Dyson swarm expands over more and more of the sun.


Something that would be fun as a far future thing is to have someone go back and see what happened there... would be a big trip though. The whole existing story timeline would fit In the time it takes to get back to Earth one way.

Isn't it pretty hard to get a capture of a large body like that, since something needs to brake it? Maybe it had a grazing collision with the Amillian homeworld and was captured that way. A captured moon implies the initial orbit would probably have been elleptical, I wonder what effects that would have.
Yeah, you're right... a hit would be better for it. The insane clearing in the sim might help in this; the young planets get pwned. (Of course, at that point, no object would be really big, but maybe. I'm not up on solar system formation.)

In any case, I'm ok with saying "that's just the way it happened to be" and not worry about the probability by saying it was 1 in 1000 anyway.
I imagine complex life probably could survive, especially if introduced artificially instead of having to actually evolve there, but conditions like that would definitely make the planet less friendly to it.
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

Destructionator wrote:Well, I added the other planets, and only Uranus is doomed. With Saturn there, it gets ejected even faster than before. But the other planets are all OK.

Saturn is ~ 10 AU out, and looks stable here. So for this small star, it looks like we go to more like 1/3 the distance from the companion, maybe more.

That ratio must depend on the companion's mass.
That would make sense.

I think it'd be cool to develop this system a little.

If there's a gas giant in the same place as Jupiter we might assume an inner system architecture similar to our own system. An inner Mercury-like world, a large terrestrial or two, a small Mars-like world, and an asteroid belt. Beyond the Jovian is where it starts to get alien. There's a small outer gas giant, maybe 30-40 Earth masses or maybe Uranus/Neptune sized, and beyond that a second, icy asteroid belt. Beyond that is maybe 20-30 AU of nothing; zone where the companion star prevents any stable orbit.

The red dwarf in turn we know has a hot Jupiter or Neptune, and let's give it an asteroid belt at the edge of the system. Using the 1/5 estimate the asteroid belt would be at 6 AU, maybe move it inward a couple of AU. In any case at that distance from such a dim star it would be in deep cold conditions; it might actually get more heat and light from Amillia's sun than from the red dwarf. Conditions would probably be Kuiper Belt-like.

I remember reading that as a hot Jupiter or Neptune spiralled inward it might push material ahead of it, leading to the formation of a super-Earth inside its orbit. So the red dwarf might have a big hot tidelocked terrestrial planet orbiting inside of the orbit of the hot Jupiter/Neptune.

A major issue is going to be Amillia's orbit and what it was like before the terraforming, as this will help us define where the habitable zone is relative to it, and that will help us figure out what the other planets are going to be like. The sequence of the disaster (melting of the polar ice, causing a sea level rise flooding much of the continents and drowning the polar continent so the ice cap can't reform) suggests quite low relief, which in turn suggests rather un-Earthlike geology.

Maybe Amillia is a superterrestrial planet. Geologic activity would have been high and the continental crust would have quickly (within a few billion years or less) accumulated enough that plate tectonics would lock (I read a paper suggesting this would happen). The main form of volcanism would then be hot spots, and the mountain ranges would erode away over hundreds of millions of years, and eventually the continental platforms themselves would start to erode away. Eventually most of the continents had become shallow seas; only their cores would remain above water; the rest would be shallow submerged plains. Then the planet cooled for some reason, causing large glaciers to form on some of the continental remnants, which lowered the sea level enough to expose an eroded polar continent, which formed its own large glacier, lowering the sea level some more, so when humans showed up the planet was in the middle of an ice age with unusually low sea levels exposing the submerged plains. Humans would just have to put some oxygen and ozone into the atmosphere and the planet would be habitable.

Then of course their terraforming somehow destabilized the climate. Ooh, originally the continents would have been sandy and rocky terrain. As they introduced vegetation this would have lowered the planet's albedo, causing it to warm up. The change in terrain would also have reduced the amount of particulate matter being blown into the oceans, reducing their fertility and increasing CO2 levels, which might have enhanced the effect, although it might have been counteracted by the increased carbon burial from introducing terrestrial vegetation. Anyway, the effect was enough that you started to get less snowfall and the glaciers started to melt, which further decreased the albedo, as snow and ice is highly reflective. This would work especially well if there was a large sea ice cap; sea ice is IIRC one of the easiest kinds to melt - it's thin, and heat is transported to them better than it is to continental glaciers. Warming might also have liberated methane clathrates. At any rate, you got a runaway greenhouse effect and pretty soon the land glaciers were melting and the seas were rising.

So you'd have gone from a cool world of broad, low-relief continents to a warm world with little land and huge shallow submerged plains. This would increase the fertility of the oceans, which would draw CO2 out of the atmosphere, which would cool the planet, which would raise the albedo, both by direct presence of snow and ice and perhaps by drying the climate and killing terrestrial vegetation (which would also increase the fertility of the oceans by increasing the amount of particulate matter blown into them from the continents, further raising CO2 drawdown). The planet would crash back into an ice age. Only the old glaciers would be gone, and it takes a long time to build up ice that thick, so the sea level didn't go back down, especially as the polar continent was now below sea level - especially as all that ice on it had depressed the land, and it was still springing back. Maybe the climate would warm a little again later as it stabilized, but by then between the catastrophic climate changes and being forced to abandon all the infrastructure they couldn't easily move civilization would have been devastated.

Sound good? The only thing is this would imply Amillia is several times the mass of Earth, but that shouldn't effect the environment too much - assuming similar density gravity resembles diameter, and mass is diameter cubed - to increase surface gravity to 2 G you'd need a planet 8X the mass of Earth, so Amillian surface gravity would only be mildly higher than Earth's. Their space program would have a harder time though as escape velocity from the planet would be higher.

Incidentally, another implication is Amillia might have lots of volcanic islands, as hot spot volcanism would now be the primary form of volcanic activity, and the islands would be singletons instead of chains like on Earth because the crust wouldn't move over the hotspots.
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Re: Possibility: killing FTL via slowboat colonists

Post by Destructionator »

I like a lot of where you're going. Having the planet bigger is sub-optimal though. It makes space launch that much harder, and it is opposite of the last revision.

The last revision, while still based on Earth, has a few minor differences:

a) The year is slightly different length. (did this just because a perfect match is absurdly unlikely). I never gave it a specific number, or even longer or shorter.

b) The day is slightly shorter: about 22 hours. The interesting thing here is when amillians meet humans, they are slightly off cycle. (amillians also sleep more of the day than humans, further complicating working together) They hate dealing with a 24 hour cycle.

c) The planet is actually a bit smaller, with just a wee bit less gravity. Just enough so working on Earth feels a bit weird.

I figured it has similar angular momentum to Earth, but being smaller means it spins faster, so shorter day. It has the effect of making weather that much meaner around the equator too; this was one of the things I used to justify their civilization being limited to the one island, and it introduced some more danger in setting up the equitorial launch site.


So I'd like to keep the slightly smaller planet. Think something between Earth and Venus.



Your description of the geology is generally very cool though. I like it. My old map of the world, which was just randomly created, looked like this:

Image

Similar ratio to Earth for water/land, but different layout. The red dots indicated civilization (not to scale) and the line on the bottom dot shows how long the floating mass driver that provides easy space launch is (that is to scale). See Mike Combs' "The Bridge to Space" for a story exploring that idea. I liked it a lot, so I borrowed it from him. (He, in turn, borrowed it from Gerald O'Neill.)


This can change a lot. I'm not tied to it; it was literally a random fractal that I thought looked cool enough to color in.


btw, I did the math: a Hohmann orbit out to Neptune would take 30 years, one way. So much for a five year mission to check out the other star... unless they use fancier drive tech, of course. I'll have to calculate the delta-v for a steady 0.01 g burn or something, and see if that works out more favorably. It's late tonight though, and I pissed away the whole day on this when I was supposed to be working!



But I should get to bed. I'll re-read your post tomorrow after I catch up on my work and see if I have any additional comments. I like where you are going in general, just a few little specifics I want to change if we can get it all to work out.

Then, the next thing is to get this solar system well defined and do some math on it! next step after that is to decide where the habitat clusters go. I really like solar orbit, and am leaning toward a bit inside of the planet, like 0.9 AU; more solar energy, near by for easy travel, and maybe , just maybe some NEOs to grab.
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

The idea of primal Amellia as a primordial Earth-like superterrestrial made me think of those 2.1 billion fossils in Gabon, and this in turn got me wondering. What sort of indigenous ecology might Amellia have had, and how much of it might survive to the setting's present day?

I would think at the very least there would have been bacteria. Maybe photosynthetic organisms generating a whisp of atmospheric oxygen (a few percent Earth's present atmosphere level). Possibly there might be small sea animals too, if the Gabon find is anything to go by.

As for how well it might survive the terraforming - I think it might depend on whether it was biochemically compatible with Earth life. If it was, humans could simply introduce new Earth-derived life on top of it. The introduced species would probably play hell with the ecology, but a lot of Amillian organisms could potentially assimilate into the new ecosystem. If it wasn't compatible, then terraforming might well include killing off a lot of the native ecology to make way for Earth-derived forms, and the spread of successful Earth-derived producers would probably be totally devestating to the native ecology as they compete with the native producers and (from the perspective of the native consumers) fill the food chain with inedibles and poison. Any animal that wasn't smart enough to recognize Earth life as inedible might well be extinct, and native life in general much reduced. Quite plausibly native forms would be essentially gone from everything except the deep crust and maybe some refugia like deep ocean hydrothermal vent communities (but hey, I remember reading somewhat that the deep crust on Earth might hold as much biomass as the surface ecology, so maybe that wouldn't be doing so badly after all).

Of course this is all ignoring the effects the increase in atmospheric oxygen and the climate fluctuations accompanying the fall of the colony might have had. I could see the oxygenation of the atmosphere easily poisoning most native life; even if Amellia's Oxygen Crises had already passed it might be a hell of an adjustment to go from living with a mix of, say, 1.05% oxygen to living with a human-friendly atmosphere.

Still, I kind of like the idea of some native flora and fauna surviving. It might give the local biosphere a bit of alienness. Being evolved for a low-oxygen atmosphere I imagine native lifeforms would probably be generally small and slow-moving, since they'd be evolved for an environment with much less energy available than there are to most modern Earth critters, although who knows, you might just have some large forms. The ocean shallows being haunted by some kind of big sea scorpion-like ambush predator might be cool. Hey, they might be another example of the unintended consequences of the terraforming! They were originally relatively small critters (say lobster sized), but that was because their metabolism was limited by limited food. The oxygenation of the atmosphere made a lot more energy available to the biosphere which raised the biomass of these creatures' habitats dramatically, giving them much more food, and the terraformers introduced lots of Earth-derived big creatures for them to eat, so now they grow much faster and bigger. Since they grow all their lives this means they just keep growing until they get so big their exoskeleton gets so heavy it pins them in place and they starve - but they can easily get bigger than a man before that happens!

Although that would require biochemical compatibility between the biospheres for them to want to snack on people. Maybe mention something about evidence for early panspermia between Earth and Amillia and leave it at that. Alternately, maybe they don't eat people - but they are territorial and will attack people who enter their territory.
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

Destructionator wrote:I like a lot of where you're going. Having the planet bigger is sub-optimal though. It makes space launch that much harder, and it is opposite of the last revision.
A smaller planet is harder to square with the geology. The other way I can think of to get plate tectonics to stop is to have the planet's interior cool enough that there's not enough energy to drive it ... but that would tend to come with the magnetic field and volcanism dying, which would be bad for continued habitability. This isn't necessarily a problem as the planet would be terraformed anyway, but we've seen an example of a planet where something like that happened; Mars, and it doesn't have continent-sized tablelands.

The only other way I can think of to get this kind of geology which strikes me as plausible is if something adds a lot of energy to the planet's interior, which supercharges plate tectonics. Best thing I can think is to make Amillia a habitable moon of a gas giant in the life zone with several Mars to Earth sized moons, so it can have tidal heating effect similar to Io (though less extreme). Assuming a mass of .5 Earths (should give roughly similar surface gravity, maybe a bit lighter), a second outer moon of a similar mass, and calculating by a comparison of the mass of Titan to Saturn to get the mass of both moons, you'd probably want a gas giant of around 14 Jupiter masses, which is big enough that it might be a small brown dwarf rather than a planet. The gravity well of such a gas giant would probably also be a pain for a space program, but on the plus side it would probably have a pretty large family of minor moons in easy reach. It would also probably require a revision of the day/night cycle; a gas giant moon would almost certainly be tidelocked, and even Io has an orbital period of more than 1.769 times Earth's day.

A much larger moon than Earth might be able to do it, but I'm not sure it could dramatically heat up the interior for hundreds of millions or billions of years without causing the planet to become tidelocked to the moon (which IIRC should pretty much end the tidal heating effects).

Maybe the planet could be much richer in radioactive elements than Earth so it gets a lot more radiogenic heating, but I'm not sure how plausible that is.

I think our plausible options are probably pretty much either to make it a superterrestrial of between 2-3 Earth masses, make it a gas giant moon, or think up a whole different scheme for the geology. Which would you prefer?

Personally I think a superterrestrial wouldn't be that bad. The gravity would probably be a little bit different from ours but not too much like you describe, just in the opposite direction (Amillian gravity would be a bit higher). It would make a space program harder but if they were more willing to use more fuel-efficient engines like nuclear thermal rockets an Amillian space program would still be quite doable. The added cost of launching commercial sattelites might just actually push an earlier development of space resource exploitation.
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Re: Possibility: killing FTL via slowboat colonists

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Somes J wrote:I would think at the very least there would have been bacteria. Maybe photosynthetic organisms generating a whisp of atmospheric oxygen (a few percent Earth's present atmosphere level). Possibly there might be small sea animals too, if the Gabon find is anything to go by.
Yes, having native life is a big bonus. I pondered up a couple things that would be nice to keep. One scary thing about having the life too advanced though is how does this play with the Great Filter(s)?

The more we shove in here, the higher up the bigger filter must be on the chain. I think I prefer it that way though. Say life is 1/1000 stars. Multicellular can be 1/2. The painful part will be space possible intelligence. Let's call that 1/1000000. (Intelligence itself can be fairly common, but enough of it applied toward the endeavor? The environment also needs to be friendly enough to let them try too. One in a million might be too low; several little factors all combine at this step.)

We're now looking at one in two billion. That still leaves a couple hundred space civilizations in the galaxy. Why aren't they here? Next level of the filter: let's say part of getting to space is putting more resources in the hands of individuals, rather than expanding the group. Thus, the odds of a space civ actually expanding interstellar are rather low, since they just don't grow that much. (This is where humanity seems to be going in reality, as well as the last iteration of this 'verse. I had to use technology and politics to explain they maintaining the replacement rate in the face of the evidence! I'm just handwaving it here for now.)

This puts us within an order of magnitude of it being just humans who expand interstellar, and that seems ok, and we can go fairly high up the life chain here without breaking things. High up is good for plant life too. Easy to forget that plants are just as complex as animals in many ways - the odds of having a vegetative world would be just as low as an animal inhabited one. I like vegetation.

If it wasn't compatible, then terraforming might well include killing off a lot of the native ecology to make way for Earth-derived forms, and the spread of successful Earth-derived producers would probably be totally devestating to the native ecology as they compete with the native producers and (from the perspective of the native consumers) fill the food chain with inedibles and poison.
It might go the other way around, in parts of the world, too, with the natives winning the battle. I imagine lots of it wouldn't be decisive, with earth and native life living side by side; no one species really dominates an ecosystem irl, even if the competition is generally incompatible.

There'd probably be an extinction event of epic proportions with the introduction of the new life and human action (typical human colonists, exterminating the natives), but the percentage that survives may be mixed right in.

Imagine a biologist looking at that. Two completely different life forms, right here. Their theories on life would surely be very different than ours.

(Then, they look in the fossil record, and see huge weird ass shit happening some 9000 years ago, with the new life being introduced right then... much like how I had intelligent design be taken somewhat seriously in the old revision, alien seeders would have to be taken quite seriously here, even before they confirm alien life by other means. It would probably be little surprise when they spot that starship coming with the other batch of colonists; by then, the biological and geological record would give strong evidence to the terraforming theory, and astronomers have likely spotted the Dyson swarm around Sol. Very strong evidence for alien life.)




Ocean life, I can see as sticking with more native than land life, if for no other reason than humanity doesn't want to live there, so they focus less upon it.

Of course this is all ignoring the effects the increase in atmospheric oxygen and the climate fluctuations accompanying the fall of the colony might have had.
Oh, it'd surely wipe a huge number of them out.

But the survivors might be really weird. I remember someone on sdn (mayabird I think) saying that the time of the dinosaurs had Earth with much more oxygen in the atmosphere than we have now. A result of that is insects could grow bigger; a little easier to fly, and a lot easier for their primitive gas exchangers to work, so less energy required, much much more available.

The writer said it was likely that there were giant insects flying around back then!

Googling it, this appears to be confirmed with fossils: http://en.wikipedia.org/wiki/Meganeura


Imagine an effect like this. Little things surviving off the small oxygen suddenly gets a huge influx of it. And they grow (relatively) gigantic!



There was a rule in the old revision: if you are going outside the walls of the spaceport at the equator, carry a weapon. I see that advice doubling now.

(I created a little alien animal for the tsw verse here: viewtopic.php?p=6477#p6477 Includes a sketch a friend drew from my description too, very cool and I didn't want to ditch it, so I incorporated it into amillia as one of the equatorial life forms.

Anyway, the space port wanted to be built there for physics reasons, but these critters didn't like having their territory encroached upon and fought back, showing their intelligence by using stones, clubs, and primitive group tactics. But iron age* armored knights beat back these stone age animals easily enough, and then the first thing built at the spaceport location was a 10 foot tall wall to keep these guys out. A human might climb it, but these guys are shorter than humans so it did the job. They accepted that the walled city was the outsider's territory and would back off it, but if you went far beyond those walls, they'd likely attack.

* Say, what's iron age knights doing building a spaceport? Simple - war technology never had a paradigm shift (iron swords replaced with steel, but at the core of it, they are still swords) while space tech advanced. In their eyes, swords and pikes were just the way you fight. They've done the job for a thousand years, no need to change what works. Add in the stabilizing influence of the old conservative (unified) monarchy and you might get new fields of tech opened up, like space boosters, but replacing something so firmly entrenched would be a rare event without outside influence.)

Hey, they might be another example of the unintended consequences of the terraforming! They were originally relatively small critters (say lobster sized), but that was because their metabolism was limited by limited food. The oxygenation of the atmosphere made a lot more energy available to the biosphere which raised the biomass of these creatures' habitats dramatically, giving them much more food, and the terraformers introduced lots of Earth-derived big creatures for them to eat, so now they grow much faster and bigger. Since they grow all their lives this means they just keep growing until they get so big their exoskeleton gets so heavy it pins them in place and they starve - but they can easily get bigger than a man before that happens!
Awesome.

Perhaps instead of necessarily starving, they switch to a kind of filter creature. So passing water or fish gives them something to eat for a while. Then, they'd probably die off anyway as the volume is insufficient, but you might have a life cycle:

1) Tiny, floats around doing its thing
2) Large. This stage is sexual maturity, if they reproduce sexually, and they go around eating and spraying gametes.
3) Just plain huge. This moved past the reproductive part of life, so they just eat, grow, and harass sailors.
4) Immobile. It has eaten so much that it can no longer move, but still survives for a while as a filter/trap. Chitin has variable density, so I can't say if it would float or not, but it probably won't; a floating critter couldn't filter water passing through.

Then, after a while of that (a few months maybe; cold blooded things can go for a long time eating very little), it finally dies, leaving an empty shell in the water. As it decomposes, it might leave gas bubbles inside and or shed some layers of exoskeleton... so the corpse floats to the top. Haha, imagine the scare as this giant lobster floats up. Experienced sailors know it is nothing to worry about, but I imagine it would look menacing!

Alternately, maybe they don't eat people - but they are territorial and will attack people who enter their territory.
They might also try to eat them, but just get nothing out of it; the incompatible life just passes through their digestive system. For any kind of filtering organism as well as many others, this would be dictated; they can't choose what they eat, so if the incompatible life going through kills them, they won't last long.

Being stupid animals, they see movement and try to eat it, not knowing if it will actually do them good or not.


Of course, territorialness is quite common too so it works just as well alone.



But hell yeah this is win. Huge amounts of diversity are opened up, so if you venture around the world, you never know what kind of strange, new life you're going to find. (and with the planet so scarcely populated by people, there's plenty of world to explore)
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Re: Possibility: killing FTL via slowboat colonists

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Another benefit here: oil.

I was thinking last night in bed that if life was imported, their home wouldn't have oil like it did in the old revision. This morning I refuted that with one word: Titan, but it bothered me for quite some time last night.

They use oil for a lot of things: their space rockets were kerosene+LOX, for one, but more importantly, burning oil is what keeps people in the eastern city warm in the winter.

I figured they could switch to burning wood if need be, or perhaps something like whale blubber, up until the point where electricity could take over, but I feared that without cheap oil, they might never grow to a size where electricity becomes viable. (In the present day, they use nukes and space solar for most the energy, but those represented a huge up front cost to build. Oil, coal, and wood are cheap and easy enough to use since the beginning of time, but production needs to be high enough for large cities. Oil is better than wood for that setup.

I shouldn't neglect natural gas either, there's a useful one that wouldn't necessarily need life (again, thanks Titan).)


But yeah, anyway, the worries go away entirely with native life. Yay.
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Re: Possibility: killing FTL via slowboat colonists

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Somes J wrote:A smaller planet is harder to square with the geology.
Blargh.

Best thing I can think is to make Amillia a habitable moon of a gas giant in the life zone with several Mars to Earth sized moons, so it can have tidal heating effect similar to Io (though less extreme).
As fascinating as it is, that removes the attractiveness of it to terraform; it is no longer just like home away from home.

I'm so tempted to through in a moon base on a moon of a gas giant elsewhere in the system though. It'd have a very interesting sky.

(In last revision, there was a colony cluster that was going to go around Jupiter, partly to get away from everyone else, and also to soak in the view. Though I fear the radiation belts would make that impossible. Bloody radiation ruins a lot of the sky fun, since you have to live underground, even on our own moon. Lame.)
The gravity well of such a gas giant would probably also be a pain for a space program, but on the plus side it would probably have a pretty large family of minor moons in easy reach.
In addition to those moons, the Oberth effect from such a large body might actually help out. You'd need to use high thrust rockets, but conservation of energy of you dumping propellant down that gravity well means you scream with speed out of it.
It would also probably require a revision of the day/night cycle; a gas giant moon would almost certainly be tidelocked, and even Io has an orbital period of more than 1.769 times Earth's day.
Yea, that is one of the bigger uncool things. Would be a cool place to visit, but not so much to live there.

Maybe the planet could be much richer in radioactive elements than Earth so it gets a lot more radiogenic heating, but I'm not sure how plausible that is.
This might work, but I think it would take too much change to work out.
I think our plausible options are probably pretty much either to make it a superterrestrial of between 2-3 Earth masses, make it a gas giant moon, or think up a whole different scheme for the geology. Which would you prefer?
The mass is the best of the lot for this... but can it work with 1.3x earth mass? That'd peg surface gravity at about 1.1g, assuming same density. 2x is 1.26g, which is higher than I'd prefer.

Even small changes in gravity changes a lot of things, more than just space launch difficulty. A spy satellite will be moving faster at the same altitude from the ground - 8.4 km /s with 1.3 mass, vs 7.7 km /s with 1.0 mass. So launching it is harder, and once it is up there, it can't do as good of a job. It'd also hurt adjustment; if the people are used to bigger gravity, would that make adjusting to and from freefall harder? I don't really know, but I assume it would.

That 10% change in delta-v will be a pain to rectify in shuttles too. Much reduced payload thanks to the exponential nature of the rocket equation. That's not a dealbreaker though, it just means smaller payloads. I'm guesstimating about a 26% reduction based on quick calcs.


So bah, I'm resistant to it. Not completely closed, but what other geologies do we have?

Let's instead of giving a big change to mass, what if it was just a bunch of small changes across the board. So we'll start by giving the system more angular momentum to begin with.

The planet is spinning very quickly early in its life, leading to lots of movement inside. When the moon arrives (however it does), it is moving pretty quickly too. We can thus have a more massive moon, closer in to the planet. The tidal forces will ever so slowly be slowing the planet's rotation, but it is still moving faster than Earth (slightly) when storytime hits.

Nevertheless, these tidal forces contribute to the geological activity, adding to the existing angular momentum to help keep it going inside.


The next thing is to increase the concentration of radioactive elements, just a little bit. Say the whole solar system is like this, so there's a bit more uranium and other fun in the asteroids too. Its proto-nebula just happened to be packed in this stuff, and young enough so it hasn't all decayed yet.

This further contributes to keeping things active.


Now, we hit the mass, but in single digit percents so gravity contributes a bit more to the action, but doesn't break anything else.


The idea is to get basically the same result without making a big change in any one area. Less plausible, surely, but I'm ok with it. Another benefit is probe scans from the colonists might not take all these little things into account, so it can take them by surprise when they show up. (A much larger mass would have to be known to them ahead of time.)

This contributes to the people who want to just stay in their spaceships: this planet is close, but not exactly what they bargained for, and some folks see trouble coming. The others dismiss them as worrying too much about some changes that are probably nothing.

Hard science causing the schism, hehe!


The parameters of the disaster might have to be slightly tweaked too, probably a bit more mild, but that's not so bad. We keep most of it.


Something about the high erosion mentioned, I like mountain ranges and have two I want to keep: one near the nation's capital, and another near that spaceport. I figure they were formed up on extraordinarily high land to begin with (which is why it remains above sea level even as most everything else sank), so the mountains were less brutalized by the water after forming and stuck around. The rest can all be volcanic stuff created on little, fresh islands. Probably coming and going over millions of years.
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Re: Possibility: killing FTL via slowboat colonists

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Thinking about Uranus again on that tilt thing, I'm actually thinking it is worse that I thought yesterday - despite rotation, one part would be pretty much all day, and the other all night. Man, that would be kinda hard to live in.
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

Incidentally, in regard to the moving moon thing a few posts back, something occurred to me:

Moving moons between solar systems is actually feasible if you're patient enough. Let's say you can get it up to 30 km/s. That's roughly 1/10,000th the speed of light. So 100,000 years to move it to a system 10 light years and 1 million years to move it to a system 100 light years away. Given that it's speculated that a major stage in planet formation involves collisions of lots of Luna to Mars sized planetessimals a solar system during this stage of formation would give you lots of potential bodies you could borrow. Sure, megayear construction times sound insane to us, but maybe not to some other species, and a few million years is trivial in terms of cosmic time.

This is good because something I didn't realize before I started thinking about this is that Luna is actually really quite large. Uranus's biggest moon is ~1/21 its mass. Eris, the biggest KBO/scattered disk object known is less than a quarter its mass. Triton is less than a third its mass. And all these objects would lose a lot of mass from evaporation in the inner system; the rocky core left behind when the ice layer is gone might have as little as half the original mass. Unless the system has some fairly large gas giants if you want a Luna-sized object you'd likely have to either create or import one. Unless you're lucky and one of the terrestrial planets has a suitable moon, just the wrong one (one outside the habitable zone). Or maybe if the system has a Mercury like world you could use that.

Actually there's an interesting question. Which one would be harder and take longer: importing a Luna-sized body from another system or smashing five or ten big KBOs together to make one?

Anyway, the upshot is I was fretting over arranging the timeline so that a moon around ~1/8-1/6 Luna mass would still be able to serve its stabilizing function by present day, which means the terraforming project couldn't have been more than a couple of hundred million years ago. Now I have a lot more freedom with the dates. I could make it billions of years ago if I want easily. I like it further in the past for a couple of reasons. I like the idea of these worlds being truly stable - for all practical purposes natural garden worlds - with biological histories of comparable richness to Earth. And I kind of like the idea of having a second terraformer race in the relatively recent past (a few million years ago), and this would give them something to do - in billions of years a whole new crop of terraformable worlds would have formed.

As an aside, I wonder just how fast you could move a planetoid without needing to consume an appreciable fraction of its mass for propellant. Maybe set up a bunch of particle beams on one side and point them up at the sky, shooting out relativistic particle beams. I suspect thrust to power ratio would be lousy, but fuel efficiency would be great, and you've got a big moon's worth of rock for a heat sink. I wonder if relativistic speeds might actually be feasible and sanely doable (for certain values of sane - if you could do this it'd be vastly less trouble just to build a lot of habitats).

Now there's some nice superweapon potential. Hit them with a moon going at a significant fraction of c! I doubt it'd actually be very practical as a weapon though.

---------
Destructionator wrote:Yes, having native life is a big bonus. I pondered up a couple things that would be nice to keep. One scary thing about having the life too advanced though is how does this play with the Great Filter(s)?
Personally I lean toward sapience as the most plausible Great Filter, in which case primitive plants and animals shouldn't be an issue.
and astronomers have likely spotted the Dyson swarm around Sol. Very strong evidence for alien life.
I wonder how long a two-way radio message would take.

Of course, they might not try it. Somebody out there is doing astroengineering - what if they're not friendly? Maybe not such a good idea to draw their attention when you don't know anything about them...
Ocean life, I can see as sticking with more native than land life, if for no other reason than humanity doesn't want to live there, so they focus less upon it.
If we go with a primordial Earth model I doubt there would be any indigenous land life, beyond some bacteria and lichen-equivalents and the like. Complex plants and animals only seem to have colonized the land on Earth less than half a billion years ago, by which time oxygen levels were in the same ballpark as present day.
But the survivors might be really weird. I remember someone on sdn (mayabird I think) saying that the time of the dinosaurs had Earth with much more oxygen in the atmosphere than we have now. A result of that is insects could grow bigger; a little easier to fly, and a lot easier for their primitive gas exchangers to work, so less energy required, much much more available.

The writer said it was likely that there were giant insects flying around back then!
I think you may be thinking of the Carboniferous. A bit before the dinosaurs, but you're right, oxygen was 30-35% compared to around 21% today, and it's thought to be the reason you had such gigantic insects. That and I suspect another factor might have been a relative lack of competition from more physiologically efficient vertebrates.
There was a rule in the old revision: if you are going outside the walls of the spaceport at the equator, carry a weapon. I see that advice doubling now.
Well, like I said I doubt there'd be much indigenous land life. Hmm, there might be some river creatures that would become (relatively) huge in response to the changing environmental conditions and adopt a niche similar to crocodiles.

Hmm, I wonder if gill-equivalents evolved to breathe in water in a ~1% oxygen atmosphere might be able to function in air in an atmosphere much higher in oxygen? Maybe not very well, not enough to actually let the creature live like that long-term, but if something could survive limited periods out of water like that some native critters might have started to forage or hunt on land.
Perhaps instead of necessarily starving, they switch to a kind of filter creature. So passing water or fish gives them something to eat for a while. Then, they'd probably die off anyway as the volume is insufficient, but you might have a life cycle:
Maybe. I envisioned them as probably being largely slow/immobile ambush predators anyway; I imagine life adapted to a low-oxygen atmosphere would probably be fairly sluggish. The upside is, like cold-blooded reptiles, they wouldn't need much food for their size.
Then, after a while of that (a few months maybe; cold blooded things can go for a long time eating very little), it finally dies, leaving an empty shell in the water. As it decomposes, it might leave gas bubbles inside and or shed some layers of exoskeleton... so the corpse floats to the top. Haha, imagine the scare as this giant lobster floats up. Experienced sailors know it is nothing to worry about, but I imagine it would look menacing!
Cool.
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Re: Possibility: killing FTL via slowboat colonists

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Check this out:

http://arsdnet.net/flower-planet.png

That flower design on the outside is a planet I put around the red dwarf, with the math set up to have a circular orbit around it at 3 AU from the dwarf.


That weird looking design? Same thing any moon makes from the perspective of the sun, though most moons are so close to their planets (relative to the sun) that you can't see their orbits. Like the hot jupiter, seen here as a little line in the red.

You know what that means? Stable orbit! I switched perspective to the red dwarf, and it made a huge ring. The orbit isn't perfectly circular - its radius fluctuates, but it does it regularly, so it is good to go.

I tried 10 AU out of the dwarf though, and things just left the system; the pull of the little star is too weak for something that far out with the added fluctuations of the main sun. Almost the same with 5 AU. 4 AU got destabilized by Saturn; without it, it might have flown.

But it looks like the fun around the little star must be around 3 AU or within. An icebelt could probably be there, since the snow line would be moved way in thanks to its smaller luminosity.





So here's the solar system so far:

Sun, mimics our own

Planet 1: unspecified so far

Planet 2: Earth - 1 AU
moon: like ours, but more massive

????

Rocky asteroid belt - 2 - 4 AU out (like ours)

Gas giant #1 - 5 AU, like Jupiter

Gas giant #2 - 9 AU, saturn

Red dwarf star - 30 AU -> 60 AU
hot jupiter - 0.3 AU
ice belt - 3 AU

Outer belt - 80 AU or something obscene like that. We won't really be traveling out there.


I'd like to move the rock belt and the jupiter in more, to make travel time to them smaller. Then perhaps swap jupiter and saturn because I like rings. Planet #1 I'm thinking might be a gas giant core that had its atmosphere blown away... so it'd be a HUGE ass mercury.

I'm really tempted to make it yet another hot jupiter, but rocky planets are underrepresented here. Of course, all those gas giants could have giant rocky moons.

The colony clusters aren't set down yet. I still like 0.9 AU or something like that, so it has low delta v and travel time.

None of this is set in stone, it's just what I have so far. I'm open to add, remove, edit, everything.
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

Destructionator wrote:Thinking about Uranus again on that tilt thing, I'm actually thinking it is worse that I thought yesterday - despite rotation, one part would be pretty much all day, and the other all night. Man, that would be kinda hard to live in.
On the other hand, if complex terrestrial life did manage to survive the adaptations would be fascinating. I think I'm going to include an Earthlike planet that rotates on its side like Uranus in my uni; I'd love to project what the ecology would look like.
Destructionator wrote:Yea, that is one of the bigger uncool things. Would be a cool place to visit, but not so much to live there.
I don't see why you couldn't have a clement climate with a moderately longer day/night cycle. You'd want more greenhouse effect than Earth, and a thicker atmosphere and long skinny continents (lots of maritime climates!) would help too. Putting it further from the sun might help too - moderate the heat during the long days.
The mass is the best of the lot for this... but can it work with 1.3x earth mass? That'd peg surface gravity at about 1.1g, assuming same density. 2x is 1.26g, which is higher than I'd prefer.
Maybe if the star is older than Sol. Here's the paper where I'm getting the information from. There's a graph on page 44 that shows the relevant function. If I'm reading it right the second line from the bottom represents 50% continental crust cover, which is the point they think plate lock may happen. It's hard to get it by eyeballing but it seems to cross the 1 Earth mass line at maybe 6-8 billion years. Unless the star is dimmer than Sol the life zone's inner edge will probably be past 1 AU by that point, you'd probably want to move the planet a little farther out than Earth is for it to get the same level of sunlight today. The graph actually looks better for this to happen to a small planet than I remembered it being, but potential platelock gets much earlier above 1-2 Earth masses.

Incidentally, I got the paper from here which is a total gold mine.
So bah, I'm resistant to it. Not completely closed, but what other geologies do we have?
Giving it a little thought, I think a modified version of our scenario could be compatible with an Earthlike geology. The sticky point was I wanted a polar continent that would be completely drowned after the polar ice cap on it melted, preventing it from reforming after the climate cooled again and keeping sea levels high. With an Earthlike geology a whole continent that flat is a bit weird - maybe if it had minimal tectonic activity for a very long time. With a superterrestrial with eroding continents it became much more plausible. But I don't think it's really necessary. Just have the sequence of events go something like this:

1) The spread of Earth-derived vegetation over the continents lowers the albedo and warms the planet. This causes the glaciers to begin to retreat, which further lowers the albedo. A rise in CO2 due to reduced fertility of the oceans from less particulate matter being dumped into them from the no longer barren continents may also contribute. The colonists account for this, but underestimate some critical factor (maybe a large marginally stable methane clathrate deposit in a shallow polar sea?).

2) A runaway greenhouse is initiated. The planet's large polar ice caps melt, dramatically raising sea level. The colonists are forced to flee into the previously uninhabited highlands, abandoning much of their infrastructure in the process.

3) A dramatic cold-snap occurs, leading to a short-lived ice age. The cold snap further devestates the colonists. Over time the sea level may drop as ice builds up, again exposing the coastal plains and their ruins.

4) The climate warms again, once again flooding the coastal plains. This may be the final straw for civilization, people having again started to move down into the plains, or it may already have been gone by this point.
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Somes J
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Re: Possibility: killing FTL via slowboat colonists

Post by Somes J »

Some thoughts and suggestions for the rest of the star system:
Destructionator wrote:But it looks like the fun around the little star must be around 3 AU or within. An icebelt could probably be there, since the snow line would be moved way in thanks to its smaller luminosity.
The dwarf is supposed to be similar to Wolf 359, right? Looking at Solstation, Wolf 359's habitable zone is .005 AU, or only 750,000 km! A quick calculation tells me that if you were 50 million km (1/3 of an AU) from the red dwarf and 40 AU from the Amillian sun you'd be getting more heat from the Amillian sun! An object at 3 AU should have Kuiper Belt-like conditions.

If we want an actual hot hot Jupiter or Neptune around the red dwarf it might be a good idea to make it a bit brighter. Could you even get a stable orbit that close? I tried running a 750,000 km orbit on a .1 Sol mass star on gravity simulator and it wasn't stable. Then again, I didn't adjust the sun's diameter.
Planet 1: unspecified so far
Maybe a tide-locked Mercury-like world. The nightside might be a significant source of volatiles in the form of frozen volatiles left behind by impactors in craters - since it that side of the planet never faces the sun such ice could easily exist despite the close proximity to the sun.
Planet 2: Earth - 1 AU
moon: like ours, but more massive
Would imply higher tides, unless it was farther away from the planet. Just something to consider.
????
I'm thinking a Mars-like world.
Gas giant #2 - 9 AU, saturn
I'm thinking maybe a smaller world, more like Uranus/Neptune sized or somewhat bigger (30-40 Earth masses), or maybe even a large icy superterrestrial (< 8 Earth masses) instead of a gas giant. I'm thinking that the gravitational effects of the binary may have stunted the planet's growth somewhat, in the same way Jupiter might have done for Mars. Also it makes the system seem a bit less like a complete mirror image of ours, which I think makes it more interesting. I also think a nice idea would be to have an outer icy asteroid belt beyond the final gas giant, where the gravity of the companion star may have prevented a planet from conglomerating, again in something of a mirror of the effect the gas giant has on the inner system.
Red dwarf star - 30 AU -> 60 AU
hot jupiter - 0.3 AU
ice belt - 3 AU
Suggestion: a hot tidelocked superterrestrial planet inside the orbit of the hot Jupiter. This fits with a theory that a hot Jupiter may push material in front of itself as it spirals in, leading to the formation of hot inner terrestrial planet from that material. And it's just an idea I find appealing. Especially since that close to the star the hot Jupiter may not be able to retain any moons, so it gives something interesting in the vicinity besides the gas giant itself.

I also think the hot Jupiter should be moved further in if we want it to actually be hot. .3 AU isn't going to be particularly hot even for a large red dwarf. The M2 (relatively big and bright) red dwarf Lalande 21185 has a habitable zone at .22 AU according to Solstation. I'd make its orbit < .1 AU.

As a hot Jupiter migrates inward it may drag in large quantities of volatile-rich material, leading to quite wet terrestrial planets. I imagine the red dwarf might have several icy terrestrial planets, and beyond that there might be a family of small gas giants (maybe Uranus/Neptune sized). With up to 3 AU to form in and such a dim star this might be quite an extensive family. If we go with the outer planet stunting model, there might also be an icy superterrestrial planet close to the edge of the system, inward of the outer asteroid belt. So perhaps:

Hot superterrestrial
Hot Jupiter
Icy terrestrial
Small gas giants (number?)
Icy supeterrestrial
Icy asteroid belt

A neat possibility is to have a terrestrial inside the life zone. It probably wouldn't be conventionally habitable, but it might have a thick cloudy atmosphere and a hot high-pressure world ocean hundreds of kilometers deep. From orbit I imagine it would be a cloudy white sphere. Another neat possibility is a terrestrial just beyond the life zone that's sort of like a super-sized Europa with an ocean hundreds of kilometers deep covered by a thin crust of ice.

Also: clarification: do you want a true hot Jupiter or more of a hot Neptune or maybe a hot Saturn? Personally I lean toward the latter; they might be more common in the universe.
I'd like to move the rock belt and the jupiter in more, to make travel time to them smaller. Then perhaps swap jupiter and saturn because I like rings. Planet #1 I'm thinking might be a gas giant core that had its atmosphere blown away... so it'd be a HUGE ass mercury.
Problem with that is such a migrating world might drag large amounts of volatiles into the inner systems - Amillia might be buried under an ocean hundreds of kilometers deep. Perhaps this would be better moved to the companion red dwarf - it sounds similar to my own suggestion for a hot superterrestrial there. If you want something a bit more interesting than a Mercury-like world, perhaps the innermost planet could be a tidelocked Venus-like world. Alternately we could have a terrestrial planet that had suffered a truly massive impact, knocking off its outer layers, so it could indeed be like Mercury but closer to the size of Mars or larger, perhaps large enough to retain some sort of atmosphere. A Mars-sized or larger metal-rich and dense tidelocked world with a thin atmosphere would be nicely unlike anything in our solar system.

Edit: to be safe tidelocked world should have at least .1 bar atmosphere of CO2 or equivalent greenhouse effect to keep the atmosphere from freezing out. I read that in a paper on the possibility red dwarf habitable planets. To maintain that perhaps it would be a good idea to have it still have some geologic activity. Assuming a solar system similar in age to ours this would suggest a rather bigger size than Mars, maybe .2-.3 Earth masses.

I don't think swapping the planets should be necessary so you can have rings - I don't see why a Jupiter-sized planet couldn't have a Saturn-like ring system.
Participate in my hard SF worldbuilding project: The Known Galaxy. Come to our message board and experience my unique brand of terribleness!

"One is respected and judged only as a human being. It is an appalling experience."
Ursula K. Le Guin, The Left Hand of Darkness.

"Open your mind and hear what your heart wants to deny."
Samuel Anders, nBSG, Daybreak, Part 2.
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