Terraforming questions for the Group!
A) How long would a breathable atmosphere last on a world with no method of replenishment? How long before the air just escapes due to lack of gravity per world size and atmosphere type?
B) What kinds of organisms would go into a Standard Terraforming Package to be seeded on worlds slated for human development?
I don't know any canonical answer, but if I were a Traveller terraform engineer I would try to design things so it would last for a very long time without maintenance. People are basically flighty, and I wouldn't want a world of 1B people to die because someone forgot to fill up the "coffeepot" or some econut sabotaged a machine to return the planet to its natural state. For anything but low gravity, I can imagine permanent changes. For a low grav world, I'm imagining dumping a couple teratons of comet water on the world, then adding a bacteria that turns the water into O2 +H2 when O2 pressure drops below a certain threshold. That seems like it should be good for a couple million years if nothing goes wrong.
Actually, I suppose the real answer should be whatever is needed to support the games you want to play. Reasonable arguments can be made for a wide range of values.
I saw a figure for Mars of 200,000 years before it loses an Earth-like atmosphere to the solar wind. Not sure what % that was, a half life maybe.
A planet without a protective electromagnetic field will always tend to lose atmosphere quite fast; also the lighter the planet the quicker it loses atmosphere. And of course distance from the star matters too.
The takeaway was that if you can give a planet an atmosphere in the first place, maintaining it should be fairly easy, but you do need to do routine maintenance.
OK, I should probably explain why I am asking.
The Ancients thrived until they had their apocalyptic war 300,000 years ago and they seemed to have an affinity for Earthlike worlds and I could see them doing a lot of terraforming. Except the infrastructure needed to support the terraforming efforts probably got destroyed in their war, so I am getting a close approximation for how long it would take for those terraformed worlds to become hazardous or even uninhabitable. It would help to explain the number of worlds with breathable atmospheres or ones which merely require a filter mask.
It depends on (a) how good the Ancient technology was, and (b) how badly you want to simulate this beyond a plot hook.
I'm not running you down here, I'm just unsure of the context for this question.
Quote from: S'mon on June 11, 2021, 05:50:14 AM
I saw a figure for Mars of 200,000 years before it loses an Earth-like atmosphere to the solar wind. Not sure what % that was, a half life maybe.
A planet without a protective electromagnetic field will always tend to lose atmosphere quite fast; also the lighter the planet the quicker it loses atmosphere. And of course distance from the star matters too.
The takeaway was that if you can give a planet an atmosphere in the first place, maintaining it should be fairly easy, but you do need to do routine maintenance.
Of course if the machines that maintain the atmosphere fail, and the planet loses atmosphere over the next 200k years, does life evolve to the changing atmosphere fast enough? I envision a scenario where sapient life has not yet evolved enough technologically to deal with the problem, opening up opportunities, or complications for Travellers.
Nice idea OP. I might steal from you.
Quote from: Ghostmaker on June 11, 2021, 08:10:00 AM
It depends on (a) how good the Ancient technology was, and (b) how badly you want to simulate this beyond a plot hook.
I'm not running you down here, I'm just unsure of the context for this question.
The Official Traveller Universe evolves with new technology and scientific discoveries with each new published version. When the world generation rules were first created, it was 1977. Now in 2021, with our discovery of exoplanets and deeper knowledge of astronomy, the vast number of Earthlike worlds doesn't seem as possible. So, instead of throwing away a setting of worlds that has endured for 34 years, I'm looking for ways to explain all the numbers and the trend for worlds to be habitable or marginally habitable. Ancients terraforming that has gone awry after 300,000 years seems like a good start with lots of adventure possibilities.
Quote from: jeff37923 on June 11, 2021, 10:52:32 AM
Quote from: Ghostmaker on June 11, 2021, 08:10:00 AM
It depends on (a) how good the Ancient technology was, and (b) how badly you want to simulate this beyond a plot hook.
I'm not running you down here, I'm just unsure of the context for this question.
The Official Traveller Universe evolves with new technology and scientific discoveries with each new published version. When the world generation rules were first created, it was 1977. Now in 2021, with our discovery of exoplanets and deeper knowledge of astronomy, the vast number of Earthlike worlds doesn't seem as possible. So, instead of throwing away a setting of worlds that has endured for 34 years, I'm looking for ways to explain all the numbers and the trend for worlds to be habitable or marginally habitable. Ancients terraforming that has gone awry after 300,000 years seems like a good start with lots of adventure possibilities.
OK, I see what you're getting at now.
Terraforming is about making a planet habitable, and making sure it STAYS habitable. It doesn't do you much good if you can't turn your back without the planet losing its atmosphere or something (figuratively speaking here).
Looking at the Traveller wiki, the Ancients' tech level is, well, at the upper limits (TL 30-33). So I would presume any world the Ancients modified was going to stay modified barring external events (asteroid strike, orbital bombardment, etc.).
Now, if you want to have fun with this, the Ancients had technology sufficient to create ringworlds, Dyson constructs, and other mega-engineering feats. They might have set three moons in a stable orbit around a world simply because they thought it looked pretty.
Now, you start sliding down the tech scale, then terraforming gets a bit more limited. Humaniti, for example, might not be able to improve the atmosphere of a world if it lacks sufficient mass/gravity and magnetosphere to keep the air from sleeting off. And they might just drop huge chunks of ice into the atmosphere to modify it.
I've recently seen some pretty interesting videos dealing with this subject. I was surprised to learn that sci fi has lied to me and that Mars is probably impossible to terraform due to the lack of magnetic field- something that Traveller doesn't detail in their world stats.
And if you wanted to terraform someplace that is more suitable, it's going to take a long time (millions of years minimum, maybe billions). Our oxygen atmosphere was created by single cell plants living in the ocean and by doing so destroyed the mostly CO2 atmosphere which plunged the earth into a series of extreme ice ages that almost wiped out all life. It will take forever and it would be the toss of the dice if it would even work, so why bother terraforming?
https://en.wikipedia.org/wiki/Great_Oxidation_Event
Quote from: Hakdov on June 11, 2021, 01:51:20 PM
I've recently seen some pretty interesting videos dealing with this subject. I was surprised to learn that sci fi has lied to me and that Mars is probably impossible to terraform due to the lack of magnetic field- something that Traveller doesn't detail in their world stats.
And if you wanted to terraform someplace that is more suitable, it's going to take a long time (millions of years minimum, maybe billions). Our oxygen atmosphere was created by single cell plants living in the ocean and by doing so destroyed the mostly CO2 atmosphere which plunged the earth into a series of extreme ice ages that almost wiped out all life. It will take forever and it would be the toss of the dice if it would even work, so why bother terraforming?
https://en.wikipedia.org/wiki/Great_Oxidation_Event
What from the videos makes you think it's going to take such a long time? I would have though it would be much quicker, mainly because tailored bacteria can be used for some of the hard parts, and exponential replication makes that a pretty quick process.
Quote from: Mishihari on June 11, 2021, 05:40:22 PM
What from the videos makes you think it's going to take such a long time? I would have though it would be much quicker, mainly because tailored bacteria can be used for some of the hard parts, and exponential replication makes that a pretty quick process.
Because it takes a really, really large amount of oxygen to be created. And even if you can do this in relatively short amount of time, you are still going to trigger an ice age because to make the oxygen, you have to destroy the greenhouse gases. Most likely, a "quick process" on a planetary scale is millions of years - and not the billions that it took naturally.
I guess your best candidate for terraforming would be some hellhole like Venus. Good luck getting anything to live there though. If you could get something to produce oxygen there and eat up the CO2 there, it might work ok but I still think it would take a very long time to stabilize.
B) I would say after the appropriate amount of water is present or added via asteroids/comets, whatever (and that's probably A LOT) you would first add microbes like cyanobacteria, algae, bryophytes, lichens, etc.
Next, assuming that soil is appropriate or that the mosses and lichens have leached enough acid to break rock into soil, add small plants and eventually larger plants. We could assume that these plants have been chosen, artificially selected, bioengineered, etc. to survive on whatever was lacking in the soil and atmosphere and would be more efficient at adding O2. I created astral wood, ( Populus astral) - a fast growing tree with a sapphire-green iridescent bark and slightly shimmering green-silver leaves related to poplar/aspen.
Eventually add small animal life like bugs and maybe some fungi.
Somewhere in there you might add machines that churn out O2 from CO2 or O3 or whatever is present. There are lots of artwork online that are really evocative for this atmosphere building concept.
My players PCs are mostly scientists. Early in my current campaign, they got a several month contract to monitor and analyze the progress of terraforming a world in its advanced stages. Found all kinds of stuff, like a scout wreck that crashed 105 years ago, evidence of a false pirate base that the navy planted to try and lure in criminal wannabes, the PCs even had to evacuate because of one of many scheduled ice bombardments.
Hope this gives some ideas for what you want to do.
For oxygen, I'd say dump a bunch of comets on the planet. Now you have water. Add tailored microorganisms powered by sunlight that produce oxygen and reproduce exponentially, and you're good to go. Positing science that can produce such microorganisms, of course.
Quote from: Hakdov on June 11, 2021, 01:51:20 PM
Mars is probably impossible to terraform due to the lack of magnetic field
There's some interesting discussion now around simply creating a magnetosphere. Put a powerful enough magnetic field at the L1 point and you'd have it. Doesn't have to be as strong as earth's, 11% of earth's would work.
At that point its an engineering challenge. A 300 ton space station could do it. Cost aside, we could technically do it now, but we'd be resupplying a fission power plant every two years. A better fusion power plant would be much preferred, but by the time you're thinking of far future or Traveller levels of tech that can be taken as a given.
https://medium.com/our-space/an-artificial-martian-magnetosphere-fd3803ea600c
Quote from: Mishihari on June 11, 2021, 10:27:22 PM
tailored microorganisms powered by sunlight that produce oxygen and reproduce exponentially... Positing science that can produce such microorganisms, of course.
40-50% of the oxygen in our atmosphere comes from algae. If you can get to liquid surface water it's easy.
Quote from: Dave R on June 12, 2021, 10:13:58 AM
Quote from: Mishihari on June 11, 2021, 10:27:22 PM
tailored microorganisms powered by sunlight that produce oxygen and reproduce exponentially... Positing science that can produce such microorganisms, of course.
40-50% of the oxygen in our atmosphere comes from algae. If you can get to liquid surface water it's easy.
Our algae involved on top of other organisms and had their organic material available. The part I thought might be hard is making something that can live off existing inorganic material and sunlight if the world did not have life to begin with. It seems like it should be possible with Traveller technology though.
Quote from: Mishihari on June 12, 2021, 05:03:56 PM
Quote from: Dave R on June 12, 2021, 10:13:58 AM
Quote from: Mishihari on June 11, 2021, 10:27:22 PM
tailored microorganisms powered by sunlight that produce oxygen and reproduce exponentially... Positing science that can produce such microorganisms, of course.
40-50% of the oxygen in our atmosphere comes from algae. If you can get to liquid surface water it's easy.
Our algae involved on top of other organisms and had their organic material available. The part I thought might be hard is making something that can live off existing inorganic material and sunlight if the world did not have life to begin with. It seems like it should be possible with Traveller technology though.
Algae is at the base of the food chain and thus isn't heavily dependent on other organisms, there are plenty of extremophile microbes, and we have the technology today to alter genes (CRISPR). You could create something like a primordial soup, then add cyanobacteria (blue green algae). The oxygen crisis mentioned up thread is a thing, though. Oxygen is poison, and there might be a need for a succession of microbes with different degrees of oxygen tolerance. One set probably wouldn't be enough, which suggests a delicate process that requires continual monitoring and restocking.
Isaac Arthur has a lot of good well informed videos on this kind of thing, eg:
Quote from: jeff37923 on June 11, 2021, 10:52:32 AM
Now in 2021, with our discovery of exoplanets and deeper knowledge of astronomy, the vast number of Earthlike worlds doesn't seem as possible.
There seem to be planets around the vast majority of stars, and many planets in the habitable zones of stars. Major impediments include:
1. Most stars are red dwarfs, and most red dwarfs are unstable flare stars
2. Most planets don't have a significant electromagnetic field
3. Few, possibly extremely few, planets may have plate tectonics, which may be vital for habitability.
But the jury is still out on the frequency of life-supporting worlds, they could still be fairly common.
I don't see why the Imperium at Tech 15 (at least as defined by the LBBs) would not be able to terraform planets (not quickly), or at bare minimum, keep terraformed planets liveable.
Though, its notable how many Traveller planets are only semi-habitable, aka you need some level of survival gear to exist. Perhaps those planets are the ones where the Ancient's tech has started collapsing...or they're perfect atmospheres for some other race.