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Thread: Light level on a fictional moon

  1. #31
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    Quote Originally Posted by wmatanner View Post
    Yeah, it is work. This project is kind of a professionalization exercise as well as building up enough material to approach agents. The real job thing is tough. I taught English in Japan for several years, which gave me enough time to teach myself how to write. Now I'm in an English PhD program which both feeds and inspires my fiction, while leaving me little time to actually practice it, except for this one summer. So hopefully having started the writing this month, hopefully over the year I'll be able to plug away at it bit by bit and have something to start sending out next summer.
    I've got several treatments written for a series, which is way ambitious I realize. I just need to sit down and write the scripts. I've only actually completed one full script, and that was for a sitcom in a writing class.

    I've focused primarily on the ~3000 years the moon has been colonized, but I had been trying to think of some way that perhaps the moon is terraformed for several millennia before the colonizers get there. I toyed with time dilation effects, but the only thought I have is that we are able to develop near light speed travel (say .99c or greater), and we send the ships in deliberately timed waves at *different* velocities. (I ignore acceleration/deceleration in the following calcs, and assume all ships leave at the same time.) Let's say the moon is 3000 LY from Earth. Thus the first wave of ships are huge generators that automatically land at power sources and begin the terraforming process, landing at (from 0) year 3030. These ships also carry microorganisms to seed the planet. Then a wave at say .9c carrying plant life, landing Y3333, when the atmosphere is sufficiently prepared. Ships with animals at .7c = Y4286, and finally human ships at .5c arrive Y6000. Apparently, we must've invented some really incredible stasis technology--I realize that's a problem. But anyway, assuming everything worked out as planned, colonists step onto a planet with an ecosystem already well underway; if not, they find a desert world and perish.
    I wouldn't worry too much about the stasis tech, unless you want to talk about it here just to have some background. We've had threads on ideas and new developments. One new idea published recently used magnetic fields to keep ice crystals from forming until the subject was supercooled enough that the sudden removal of the magnetic field allowed it to solidify instantly (vitrification) with virtually no ice crystalization and related cell damage. There's the idea that radiation damage means that cryopreservation can only last for about 1000 years, so perhaps the colonists need to be awakened a few times, so maybe they get status reports about the planet's automated ecopoiesis/terraforming.

    This is based on terraforming ideas I've read about before where life is staged in steps. I might consider creating another thread to see if people have some thoughts on this side of it. I hadn't thought of the imported bacterial life interacting with this organism, however. I think that's a fantastic idea. They could borrow genetic information from the newly established biosphere first to help them adjust to the atmosphere, then to adapt to our physiology.
    Go ahead and start a separate thread for that. We've had some discussions of ecopoiesis and terraforming previously you might look up too.

    Something else to consider: there's been a recent advance in creating life from scratch in a lab that might be useful. It's not about creating new life, but about constructing life from existing designs. The next step well be to create custom designs. So, it's plausible that the genome for the native microbes might be recorded and sent to the ship with the humans and then synthesized to see how it and the human immune system will react to one another (did they use something similar to this in Avatar?). You can take it from there in a way that accident or intentional introduction allows humans and microbes more time to adjust to each other beyond the time of active colonization with human presence on the moon. Might also explain the difference between that atmospheric strains and the one in humans. Of course, the additional timeframe for the duration of flight might not be that much longer if you account for time dilation effects.

    I have been thinking that. I've been fascinated for a long time by the idea of a diffuse organism, like a brain but with all its cells scattered and self-sufficient. Rather than thinking of them as little neurons with axons and such, though, I was thinking of them as more like biological computers. Perhaps their bioluminescence allows their bodies to act like binary code. They might also use magnetism in some of the ways you suggest. I like the idea of preference for temperatures allowing for different magnetic properties. I do indeed want them to be "intelligent," but basically in a way that is unrecognizable to humans. I am endlessly annoyed by the preponderance of anthropomorphic aliens in sci-fi, as if life on Earth were the blueprint for the galaxy (though perhaps the smartest example of this would be Larry Niven's Ringworld). I think it's very unlikely we'll ever find life that resembles humans very much at all, and sci-fi seems to show a lack of imagination by continuing over these old ruts. I like to try to think of how life and intelligence, if there are even things out there we might be able to recognize as life and intelligence, might look nothing like what we have on Earth. I've been toying with the idea of a single-celled version like this since high school.
    I had mentioned something like a neural net, but the communities of microbes might form logic gates like a computer chip. They will need to be physically connected in at least small groups to make loops in order to use the magnetic sail idea, so together they might make either a single gate, or a circuit of multiple gates. I'm not sure how much computation an individual microbe could perform, although if you're using magnetosomes as the root of computation then some magnetotactic bacteria have been discovered to have a wide array of shapes and sizes of particles and a wide range of numbers and arrangements of particles. So maybe that could work.

    Still, I think it would need to approximate a neural net because even a computer chip can only do so much on it's own as it's wired to do. And though the microbes could change their connections with each other to form different logic circuits, I'm not sure if there's a way for them to run "software" like we do with silicon chips, but maybe there's a way.

    I just meant that as the moon turned around the planet, the organism might find it necessary to follow the light side around in order to maintain a constant source of energy. Or perhaps they go dormant at night. Or maybe they can even store enough energy to power themselves through the night like little solar cells.
    Oh, I gotcha now. The microbes may simply run on stored energy at night, like bacteria. Or it may rarely get dark enough to not be able to use photosynthesis, except during eclipse.

    You're quite right, actually. I won't go into that side of it, though.
    No problem, I understand. If you do want to collaborate on stuff beyond the plausible science and tech, just lemme know.

    Sorry, typo corrected. Yes, I meant anemia. I'm imagining a soil considerably more saturated with iron than ours, which would be absorbed into the plant life, so that might help. But yes, their bodies might also be inclined to make up for the iron deficiency by desiring iron-rich foods, good idea. I didn't know about Hemochromatosis...That is rather serendipitous, as my colonists all happen to be descendants of the British, and so the fact that 10% of Celtic people are carriers is rather awesome (I guess I shouldn't be so excited about a disease, especially being almost half Irish myself...). The environment could definitely end up selecting for these people and causing the gene to express more, especially in the smaller gene pool. As for women, I considered the fact that they would be more prone, but as humans adjust to the environment, especially with these other considerations you've brought up, this should level out.
    Yeah, I'm half Irish too and a doc half scared me to death and made me think I was going to be dead in ten years when he thought I had HH. Depending on your plot, it might be useful to have a variation of people in whom the microbes might find it easier to be symbiotic vs. pathologic, or how susceptibility can be either cyclical or environmental.
    Et tu BAUT? Quantum mutatus ab illo.

  2. #32
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    Quote Originally Posted by wmatanner View Post
    Hi everybody. If anyone is interested in continuing this discussion a bit, I want to follow up on these ideas about flight and the magnetosphere. As it happens, having simple flying vehicles would be quite useful to my story as I'm now outlining it. I originally avoided this idea, as this story is about a technologically regressive society, which over the last 3000 years has almost completely lost the capabilities that allowed the colony to be established. However, they would perhaps be capable of maintaining some simple technologies left behind. They have mining and mineral processing technologies, water purification, etc.
    First manned flight was done in 1783 AD.
    However, of the technologies needed for a hot air balloon - fire, silk, lacquer - were there any that were not available for Leonardo da Vinci in 1483 AD, or indeed in 1483 BC?

    Lower gravity means that a hot air balloon of a given volume - needed to lift a man - is under less stress and can therefore be made from thinner cloth/paper - or lower quality, weaker and coarser materials.

    Higher atmospheric density means a man can be lifted by a smaller balloon (which also could be lighter and weaker - less material needed for the same stress).

    Once balloons are known to work, use of balloons can be sustained with low technology. This applies to hot air balloons; producing hydrogen and making balloons gastight is slightly harder.

    Regarding aerodynamic flights, Lilienthal gliders were made with wood and cloth technology, too. Again, lower gravity, denser atmosphere or both would make hang gliders easier to work with, for centuries or millennia.

    Steam powered planes have been built as toys/proof of concept. Steam engines are heavier than infernal combustion engines, by 1903 certainly. Again, make gravity lower, atmosphere denser or both, and simple timber/cloth airplanes can conveniently use steam engines.

    Man powered flight is possible - but the first pure manpowered takeoff was achieved only in 1961. The key was improving the weight and aerodynamic cleanness of the structure until it worked - barely. This required good quality manufacturing and lightweight plastics. Again, lower gravity, higher density - and pedal powered planes can be made to fly with less perfect manufacturing.

    How about no technology at all?
    The heaviest birds now known to fly - as diverse as:
    pelicans
    swans
    bustards
    turkeys
    weigh between 15...20 kg.

    However, Earth has never had less gravity, and cannot have had much denser atmosphere - yet there have been rather bigger vertebrates flying. Bird Argentavis, and pterosaurs like Hatzegopteryx/Quetzalcoatlus.

    They weighed at least 80 kg, and perhaps even 250 kg.

    Thus, in lower gravity and/or denser atmosphere, big flying animals may evolve.

    The known body arrangements of flying animals are different. Birds can stand, perch and walk on top of their feet; bats cannot stand or walk and only perch hanging under perch instead of sitting over perch like birds; whereas pterosaurs are quadripedal and walk on their folded wings and rear legs.

    If you have giant pterosaurs or different flying animals who are domesticated... what kind of animal would be able to carry a rider (where would you attach a saddle relative to the centre of gravity of the flyer? how to ensure that the saddle and rider will not interfere with flapping wings, movement of flight muscles and breathing?)?
    Quote Originally Posted by wmatanner View Post
    I want the planet to be basically habitable without support systems. I'm a bit hesitant to lower the gravity more than slightly, because it would have some extreme physiological effects, and would make movement unnatural. However, increased atmospheric pressure might be feasible. I've decided it makes more sense to move the moon's semi-major axis to about 1.5e6 km. A denser atmosphere along with aeroplankton might help protect the surface from the increased radiation, which was my original reason for the distance. I've done the corresponding recalculations for orbital period and such. Would light levels then double?
    No - quadruple.

  3. #33
    Very useful considerations. Mainly for Chorned:

    For the life of me, I still can't find anything on the internet that will explain to me how to calculate the visual magnitude of the planet (in lx). Everything I find tells me x albedo and then says, this is such and such times the full moon, etc., but no clue how they got from pt. A to pt. B. I believe the factors for this situation would be: distance from the sun, angular diameter of the planet, planet's visual albedo. I don't know how the moon's atmosphere would then affect it, but otherwise I have all other factors. Distance from sun = 1 AU; angular diameter = 6.82 degrees; if it's a Class III planet, then perhaps a Bond albedo around .12 (visual albedo perhaps slightly higher?). Chorned, you seem to know how to do this, so perhaps you can tell me what the reasonable range I have to play with, or even better how to calculate it myself. In a previous message, you suggested 90 lux if the planet had an albedo as high as Venus. Now that I've moved the planet in, quadrupling that as you say, we get 360 lux at full moon. I could make due with 300 lux, but I'd like to know what my reasonable minimum is, given a visual albedo perhaps as low as .1.

    Quote Originally Posted by chornedsnorkack View Post
    However, Earth has never had less gravity, and cannot have had much denser atmosphere - yet there have been rather bigger vertebrates flying. Bird Argentavis, and pterosaurs like Hatzegopteryx/Quetzalcoatlus.
    The thoughts on flying are quite interesting, and I'm still debating the higher atmospheric density concept. For this story, there isn't any room for animals like that, though the Quetzalcoatlus is pretty cool; I knew about the god, but not the animal bearing its name. There was a movie that came out in the seventies, around the time that thing was discovered, that played with the idea that the god was actually a pterosaur that had survived...Cool idea, but I hadn't realized they were probably basing it on this discovery.

    Quote Originally Posted by Ara Pacis View Post
    I've got several treatments written for a series, which is way ambitious I realize.
    Do you mean TV series or movie series? I think what's been done (sporadically) with TV in the last decade is remarkable, and I'd really like to work on a TV series someday. Unfortunately, sci-fi hasn't done as well in this revolution (as Joss Whedon can attest).

    Quote Originally Posted by Ara Pacis View Post
    So, it's plausible that the genome for the native microbes might be recorded and sent to the ship with the humans and then synthesized to see how it and the human immune system will react to one another (did they use something similar to this in Avatar?). You can take it from there in a way that accident or intentional introduction allows humans and microbes more time to adjust to each other beyond the time of active colonization with human presence on the moon. Might also explain the difference between that atmospheric strains and the one in humans. Of course, the additional timeframe for the duration of flight might not be that much longer if you account for time dilation effects.
    Interesting concept. You mean the time from the inertial frame of the ship rather than the planet? If we go with the .5c idea I was using before, the time dilation is negligible. Using my previous numbers, it would seem to take 6000 years from the planet's perspective, and about 5200 from the ship's perspective. If the first wave lands at 3000 years planet-time, about 2600 ship-time, it could certainly add some significant time for adaptation. What would really slow it down would be the time it would take to transmit the information. If the first wave transmitted with organism's blueprint as soon as it touched down using light-speed communications...adding a third inertial frame tends to get me a bit confused, especially since they're headed right at each other, but I guess from the ship's perspective, the planet is coming at them at .5c and the transmission at 1c, so they'll encounter the signal when they only have about 1300 more years of travel time ship-time, right? Of course, they could also use something like quantum entanglement communicators, but I'm actually avoiding that kind of technology, since I want the moon colony completely isolated from Earth, which is nothing but a myth by the time of my story.

    Quote Originally Posted by Ara Pacis View Post
    If you do want to collaborate on stuff beyond the plausible science and tech, just lemme know.
    I'm not being secretive, just didn't figure there's any reason to bring all that into this community. I'm actually a very collaborative writer, I really feed off the suggestions others bring to the work (which is why this group has been incredible), so I could definitely use more readers when I finally have a draft. I've found that I can only truly revise a work if I have other people reading and commenting on it. If you wanted to do something more truly collaborative, I might be open to that in the future. I've come close to doing something co-written a number of times, but so far none of those projects have ever gotten off the ground, and I think it would be fun.

    Quote Originally Posted by Ara Pacis View Post
    Yeah, I'm half Irish too and a doc half scared me to death and made me think I was going to be dead in ten years when he thought I had HH. Depending on your plot, it might be useful to have a variation of people in whom the microbes might find it easier to be symbiotic vs. pathologic, or how susceptibility can be either cyclical or environmental.
    Jesus, that's scary. Yeah, I've actually already been working on concepts like this. In fact, there are two different levels of susceptibility that are plot-critical. Now that I'm getting more clarity on how the organism works I might be able to refine it some more.

  4. #34
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    Quote Originally Posted by wmatanner View Post
    Do you mean TV series or movie series? I think what's been done (sporadically) with TV in the last decade is remarkable, and I'd really like to work on a TV series someday. Unfortunately, sci-fi hasn't done as well in this revolution (as Joss Whedon can attest).
    My serial would be a 7 year story arc for television. I've got the beginning and ending treated, plus a lot of tech and plot rules, but there's a lot of time to fill in the middle. I may want to shorten it up. I conceived of and wrote parts of the story as long ago as the late 80s, but it didn't start coming together until 2004. Unfortunately, several other SF series at that time started to have similar plot, background and technology elements and I was afraid mine would look derivative or like a mash-up. Although it's hard to not look similar when you're trying to avert the same common TV tropes. I think my ideas are different enough but the re-done BSG really sucked a lot of the oxygen out of the room I was writing in.

    Interesting concept. You mean the time from the inertial frame of the ship rather than the planet? If we go with the .5c idea I was using before, the time dilation is negligible. Using my previous numbers, it would seem to take 6000 years from the planet's perspective, and about 5200 from the ship's perspective. If the first wave lands at 3000 years planet-time, about 2600 ship-time, it could certainly add some significant time for adaptation. What would really slow it down would be the time it would take to transmit the information. If the first wave transmitted with organism's blueprint as soon as it touched down using light-speed communications...adding a third inertial frame tends to get me a bit confused, especially since they're headed right at each other, but I guess from the ship's perspective, the planet is coming at them at .5c and the transmission at 1c, so they'll encounter the signal when they only have about 1300 more years of travel time ship-time, right? Of course, they could also use something like quantum entanglement communicators, but I'm actually avoiding that kind of technology, since I want the moon colony completely isolated from Earth, which is nothing but a myth by the time of my story.
    I'm looking at it from an external observer (using the graph paper of the mind instead of ship-time), if the first ship arrives and sends the info back right away (moon year 0, year ~3000 from the launch date), assume the last ship (with the humans) at half the speed is only half-way there at 1500 ly distance (3000 years transit time to go), then I think they would intercept the lightspeed signal at 1/3rd the remaining distance (the ship covers .5 ly for every 1 ly covered by the signal) at 1000 ly from the destination (moon year 1000). This means the passenger ship would have ~2000 years of transit time remaining, a little less when you factor in time dilation. So, the organisms on the moon would have roughly 1000 years longer (3000 years on the moon vs. 2000 years on the ship when the last wave lands) to adapt to any alien genome introduced in the first wave, all things (speed, acceleration and time) being equal. If you want to get more specific, you might want to estimate the actual transit speeds for acceleration and deceleration, which could introduce additional variations in the timeframes. Or simplify it by referring to years of transit instead of light years. And then, you have all the years of adaptation after the landing of humans to the present setting of the story.

    I'm not being secretive, just didn't figure there's any reason to bring all that into this community. I'm actually a very collaborative writer, I really feed off the suggestions others bring to the work (which is why this group has been incredible), so I could definitely use more readers when I finally have a draft. I've found that I can only truly revise a work if I have other people reading and commenting on it. If you wanted to do something more truly collaborative, I might be open to that in the future. I've come close to doing something co-written a number of times, but so far none of those projects have ever gotten off the ground, and I think it would be fun.
    I know, but I what I mean is I don't want to ask too much or speculate too much in order to protect you and your IP. In JM Straczynski's Book of Scriptwriting (he also wrote Murder She Wrote and created Babylon 5), he mentions all the potential legal issues involved with sharing ideas or reading unpublished stories, etc. I doubt you have to worry about anyone here, and most people in the industry are on the up-and-up, but misunderstandings and can happen. (IIRC, JMS mentions a time he had to change a plot because someone suggested it to him after he had already written it but hadn't aired it and if he didn't re-write it then the other person might think he really was using their idea.) Of course, it depends on how detailed the idea is. As the saying goes, give ten writers the same setup and they'll come up with 11 different stories.

    Jesus, that's scary. Yeah, I've actually already been working on concepts like this. In fact, there are two different levels of susceptibility that are plot-critical. Now that I'm getting more clarity on how the organism works I might be able to refine it some more.
    Yeah, it kinda messed up my perspective on life for a while, and the ramifications are long lasting.

    Besides human Iron Metabolism, there's also Thalassemia and sickle-cell anemia and other conditions/diseases to consider. Also, diet may be important. I've read that eating spinach isn't enough because there's a chemical in spinach (oxalic acid) that binds iron, and so to get iron from spinach it's recommended to eat citrus with it because there's Vitamin C and citrate in citrus that counteracts it and allows the iron to be absorbed. Maybe those Brit descendents will still be "limeys".

    BTW, about those airships, don't forget that as they dump dust to feed the microbes, they'll get lighter. So, they may rise out of the microbe's aerostratum if they don't vent lifting gas (or reduce it's temperature) to trim their buoyancy.
    Et tu BAUT? Quantum mutatus ab illo.

  5. #35
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    Magnetic sail is supposed to work in solar wind - flow of charged particles. It is not going to work in neutral lower atmosphere anyway.

  6. #36
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    Quote Originally Posted by chornedsnorkack View Post
    Magnetic sail is supposed to work in solar wind - flow of charged particles. It is not going to work in neutral lower atmosphere anyway.
    That's not what the articles say.
    Et tu BAUT? Quantum mutatus ab illo.

  7. #37
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    Quote Originally Posted by chornedsnorkack View Post
    Magnetic sail is supposed to work in solar wind - flow of charged particles. It is not going to work in neutral lower atmosphere anyway.
    It can interact with a planet's magnetosphere. This was one of the earliest proposed uses for it-- to lift cargo up from small lifters to higher orbits.
    STARGAZING: All I see are the lights of a billion places I'll never go. --Howard Tayler, Schlock Mercenary

  8. #38
    Quote Originally Posted by Noclevername View Post
    It can interact with a planet's magnetosphere. This was one of the earliest proposed uses for it-- to lift cargo up from small lifters to higher orbits.
    Yes, as I understand from the research I did, mag sails are mostly being considered for slowing down vessels as they land, but could also be used as a slow but energy-efficient way of getting things into space. Chorned, I think you're referring to solar sails. I've read a lot of discussion about them being paired as a possible way of partially getting around the disadvantages of both, so that might cause the confusion.

  9. #39
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    No, solar sails use uncharged light photons.

    If magnetosails really worked, should we not be seeing technological examples around, at least as toys/proof of concept?

    How plausible could be colonial microorganisms which produce molecular hydrogen and fly as hydrogen balloons?

  10. #40
    Sorry, I misunderstood what you said about solar wind: Yes, in space the idea would be to use the solar wind in conjunction with the magnetic field.

    Robert Zubrin and Dana Andrews came up with the concept in 1985 (so the concept's still in its infancy, really), and Zubrin seems to think that you could get out of orbit and into space using "a series of perigee kicks." According to the (unsubstantiated) Wiki entry, the problem seems to be with our superconductor technology: "In theory, it is possible for a magnetic sail to launch directly from the surface of a planet near one of its magnetic poles, repelling itself from the planet's magnetic field. However, this requires the magnetic sail to be maintained in its 'unstable' orientation. A launch from Earth requires superconductors with 80 times the current density of the best known high-temperature superconductors."

    Since the focus in the scientific community isn't really *on* travel within the atmosphere, it's really hard to find any reliable articles that talk about it, as I mentioned a long time ago. It's still a fairly popular sci-fi trope, however, and I don't think it implausible to assume advances in superconductor technology (especially since I'm already assuming near-light travel, advanced cryogenics, practical terraforming, and god knows what else). I would indeed like to see some "toys," but they are perhaps prohibitively expensive. I am not terribly interested in whether or not this could be done for Earth, but rather using the unique environment of this fictional world to create conditions under which things fantastic and impractical here become part of everyday life.

    I don't fully understand the grammar of your second question. Is that a suggestion?

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