the mythical "Class M" planet

[g33k]

1 hour ago, Atgxtg said:

One problem with adapting M-SPACE for specific settings is the legalities involved. It's one thing if somebody posts something like an M-SPACE Phaser table or some such, but something else entirely to do an official M-SPACE STAR TREK supplement.

Yeah.

If there's an existing RPG for the setting, then a commercial offering is pretty much off the table (though a numbers-filed-off version might be viable).  

Modiphius obviously has this for StarTrek, and so M-SPACE won't (barring some unexpected (and frankly unlikely!) cross-licensing deal).  But the gaming-marketplace is marginal enough that I, personally, am not willing to infringe in ways that could reduce the incomes of the actual content-creators.  Personally, I wouldn't support (or even be happy to see) a "Star Trek with the Numbers Filed Off" RPG, because of the way it would hurt Modiphius and their authors/freelancers/etc.

OTOH, most Trekk[ie|er]s know the setting well enough to implement a reasonable version in their preferred general-purpose ruleset (or a sci-fi one like M-Space); and I'm fine with fans of a given system grabbing ANY setting/IP for their own use, at their own table.  AFAIK, this runs afoul of no IP/(c)/etc laws in any jurisdiction (but ianal).

Similarly, if there ISN'T an existing RPG, then I'm perfectly happy to join in with a fan-generated RPG version of the setting; but sharing/distributing this might depend on how ardently the IP-owner was defending their IP!

[Atgxtg]

Plus with Trek there are a few RPGs already out there for it that end up competing with whatever new version comes out. For example, I for one am not all that fond of d20 and so would probably prefer one of the earlier versions to whatever Modiphus puts out. I've also read that the licensing for an SF series can really bite into the profits. Apparently the game has to really sell to be worth it for the RPG company. 

 I could see someone producing a fanbook, and posting it for free, and I don't think that would hurt Modiphius at all.  If someone is that big a fan of M-SPACE or don't like the official RPG that much then it not going to change what they buy. 

What I think is more likely and probably more helpful would be simply to take bit and pieces of SF lore and tech from a setting and write them up for M-SPACE. For instance lightsabers, transporters/travel mat, warp drives, etc.  

[Conrad]

On 10/05/2017 at 7:16 AM, Pentallion said:

Sulfur is ubiquitous in the universe.  There is a very specific reason why earth can support plant life instead of it all dying off in acid rains from the high sulfur content that exists here.  It's because most of the surface sulfur was blown away in asteroid and comet impacts.  The same is not true, however, of Venus and Mars, where much higher levels of sulfur exist on the surface.  The reason why this is so has profound implications on finding other planets like ours in the universe.

As Jupiter moved further away from the Sun, it pulled the asteroid belt with it.  At a certain point, the gravitational pull of Jupiter equaled that of the Sun upon the asteroid belt.  When that happened, a vibration was created.  Half the asteroid belt continued following Jupiter.  Half fell back into the sun.  During this period, the largest planet between the falling asteroids and the Sun was Earth.  It's greater gravitational field scooped up a large amount of incoming asteroids that would have hit Mars or Venus.  As a result, Earths crust took a pounding and much of the sulfur on its surface was blown into space and carried away on the solar wind.  Mars and Venus maintained there surface sulfur.  As a consequence of this, plant life was able to form on Earth and not Venus nor Mars.

Just because we find planets in the so-called "habitable zone" doesn't mean the planets will actually be habitable.  Sulfur is ubiquitous in the universe.

That's an interesting hypothesis. Do you have any links to scientific papers on it, as I'd love to read them? I have a few doubts about it though.The late heavy bombardment period would have peppered the inner solar system with impactors. Any hitting Mars should have gotten rid of some surface material, including sulphur, due to the low escape velocity that world has. If Earth's surface was scoured of sulphur too, by impacts, then I don't see why Venus  would not suffer a similar process, since it has a slightly lower escape velocity than Earth. But not by that big a difference. Lastly, life adapts, and over time may have learned to live with a high sulphur content. The Star Trek episode involving space hippies relocating to an apparently edenic world, only to find the abundant plants, and fruit, to be deadly would be the kind of scenario that would result from plants incorporating sulphuric acid.  

[Joerg]

On ‎10‎.‎05‎.‎2017 at 8:16 AM, Pentallion said:

Sulfur is ubiquitous in the universe.  There is a very specific reason why earth can support plant life instead of it all dying off in acid rains from the high sulfur content that exists here.  It's because most of the surface sulfur was blown away in asteroid and comet impacts.  The same is not true, however, of Venus and Mars, where much higher levels of sulfur exist on the surface.  The reason why this is so has profound implications on finding other planets like ours in the universe.

There is an effect inverting this - exposure to solar wind will cause sulfides to release H2S into the atmosphere, and blow outward. The effect is negligible on Venus and Earth, but should be observable on Mars, and is significant on asteroids.

If the collision theory for the formation of our moon is correct, it didn't take meteorite impacts to vaporize the sulfur from our planet, but that single huge event which turned the clock back for it when all the other rock planets were already cooling down.

Acid rain would only be a problem on an "M-class planet" anyway - in the original reducing atmosphere of our planet, anaerobic processes reduced the sulphates to sulphides, depositing them as blackish heavy-metal-enriched sludge. This happened already before the cyanobacteria invented photosynthesis, so basically the presence of sulphates is the necessary oxidizing agent for anaerobic organisms. Sulphates and methane react to sulphides, carbon dioxide, and water under the influence of archean and bacterial microorganisms (as are active in e.g. biogas plants or our intestines). Biofilms would resist the stronger acids, which would instead consume all calcite exposed.

 

On ‎10‎.‎05‎.‎2017 at 8:16 AM, Pentallion said:

Just because we find planets in the so-called "habitable zone" doesn't mean the planets will actually be habitable.  Sulfur is ubiquitous in the universe.

I don't expect to find many habitable planets. A majority may be stuck in the Star Trek L-class, resembling our own planet before the cyanobacteria (and other photosynthetic organisms) poisoned it with oxygen.

If we find many marginally M-class planets, that would cry out for a precursor civilisation with roughly our atmospheric chemistry seeding such planets with microbial packages to make them such. They might have used von Neumann probes rather than coming there in person, in which case there would also be a significant depletion of certain elements at least in part of the system.

If sulfur is a problem for the kind of seeds planted by such von Neumann probes, I suggest that the probes themselves might mine it for e.g. ablative shielding or reaction mass. This could be a major export of a hypothetical Venus colony floating in its upper atmosphere, too.

Half of the stories about von Neumann probes have them started by a civilisation like ours. And even if we don't give them the ability to replicate and travel on, serious thought is given to terraforming machines sent before human colonists.

When looking for a "new Earth" to expand to, I fully expect there to be generations of terraforming efforts required to arrive at something moderately analogous to earth. Time which might be spent to adapt the colonists to the conditions expected at their arrival, too.

[Matt_E]

On 5/10/2017 at 2:27 PM, clarence said:

My method these days is to skip sci-fi and read New Scientist and history books at the same time : ) 

 

Wow, sounds like a recipe for real cognitive dissonance. :-)

[Conrad]

22 hours ago, Joerg said:

I don't expect to find many habitable planets. A majority may be stuck in the Star Trek L-class, resembling our own planet before the cyanobacteria (and other photosynthetic organisms) poisoned it with oxygen.

If we find many marginally M-class planets, that would cry out for a precursor civilisation with roughly our atmospheric chemistry seeding such planets with microbial packages to make them such. They might have used von Neumann probes rather than coming there in person, in which case there would also be a significant depletion of certain elements at least in part of the system.

If sulfur is a problem for the kind of seeds planted by such von Neumann probes, I suggest that the probes themselves might mine it for e.g. ablative shielding or reaction mass. This could be a major export of a hypothetical Venus colony floating in its upper atmosphere, too.

Half of the stories about von Neumann probes have them started by a civilisation like ours. And even if we don't give them the ability to replicate and travel on, serious thought is given to terraforming machines sent before human colonists.

When looking for a "new Earth" to expand to, I fully expect there to be generations of terraforming efforts required to arrive at something moderately analogous to earth. Time which might be spent to adapt the colonists to the conditions expected at their arrival, too.

You can get a lot of mileage out of the huge effort of terraforming as plotlines for scenarios. Terraforming failing may also provide such plotlines too. And planets may have been terraformed (xenoformed?) by precursor races but over vast time periods the terraforming may start to fail, due to evolution of the sun off the main sequence, or terraforming tech needing maintenance, or even terraforming organisms dying out or changing due to genetic drift. 

Edited May 13, 2017 by Conrad

[clarence]

1 hour ago, Matt_E said:

Wow, sounds like a recipe for real cognitive dissonance. :-)

Haha, well, I realized that reading about distant cultures, whether backward or forward in time, is surprisingly similar. Many historical cultures are so different from our that they just as well could have been on a different planet. Or even alien. Add technology to that and it can get quite interesting : )

 

[g33k]

9 hours ago, clarence said:

Haha, well, I realized that reading about distant cultures, whether backward or forward in time, is surprisingly similar. Many historical cultures are so different from our that they just as well could have been on a different planet. Or even alien. Add technology to that and it can get quite interesting : )

 

Indeed; IIRC more than one "alien" culture is just an ancient and/or non-Western culture, hauled down to the County Courthouse for a name-change...

[Conrad]

On 2017-5-10 at 1:13 PM, Atgxtg said:

No, but Class M planets would have to be in a habitable zone. Not necessarily a main sequence star's habitable zone, but some sort of habitable zone. Otherwise they wouldn't be Class M.

Why not have a world that isn't in the habitable zone, but is totally covered by a huge bubble (maybe of Precursor design) that absorbs all kinds of light on the outer surface and uses it to produce a fake sky and sun on the inner surface, regulating temperature to produce a Class M environment?

Edited May 13, 2017 by Conrad

[Atgxtg]

2 hours ago, Conrad said:

Why not have a world that isn't in the habitable zone, but is totally covered by a huge bubble (maybe of Precursor design) that absorbs all kinds of light on the outer surface and uses it to produce a fake sky and sun on the inner surface, regulating temperature to produce a Class M environment?

'cuz I don't know how to build one!

I probably couldn't afford to have one built for me either. It sounds a lot like a Dyson Sphere and Dyson products are pricey.

[soltakss]

3 hours ago, Conrad said:

Why not have a world that isn't in the habitable zone, but is totally covered by a huge bubble (maybe of Precursor design) that absorbs all kinds of light on the outer surface and uses it to produce a fake sky and sun on the inner surface, regulating temperature to produce a Class M environment?

So, basically a Worldhouse, a dome that covers the planet. That would work in theory, but is an awful lot of work. The effort to cover a whole planet inside a single dome, or strucutre, is enormous.

I'd create smaller domes, to provide places for habitation/farming/whatever, then perhaps encase several domes under a larger one and repeat if required. 

[...]

1 hour ago, Atgxtg said:

'cuz I don't know how to build one!

I probably couldn't afford to have one built for me either. It sounds a lot like a Dyson Sphere and Dyson products are pricey.

Here is a link to a blog from MIT about a little different sci-fi interpretation of a Dyson Sphere:

https://www.technologyreview.com/s/536171/physicists-describe-new-class-of-dyson-sphere/

It's "small" in comparison to the standard of literature, and the one I created in my Traveller milieu from the paper, is a small Dyson Sphere built around a white dwarf, with a surface area of 243,284,935,093,993 sq km versus 510,072,000 sq km area of the earth, or equivalent to 44,153 Earths. Gravity is 0.78 Earth's, escape velocity might be nightmarish though, given the diameter, at least for duration and reaction mass. A few moons worth of material, populated area is on the exterior, and it orbits another star, so it is part of a binary. Eclipse Phase has a Dyson in one of their books, Gatecrashing iirc.

Some riffs:
The Warden arrived long ago and is the station keeper on a tether to orbit.
There is a system of gates around the planet, shades of SG-1.

[soltakss]

The thing about Dyson Spheres and the like that I really hate is that they have no sense of realistic scale. Something that has the equivalent of 44,153 earths? Why would someone need something that big? How much of the earth's surface does it take to support 6 billion people? Are we saying that a civilisation needs to support, what, 200 trillion people?

[...]

That's a smaller "more realistic" one as well. problem with bigger ones is that they would take an enormous amount of material, and have practically no surface gravity. It is a question of how much territory one needs, and what pop one has; scientifically, I have a feeling that technology is an emergent quality from population level. Maybe not though, except if you just used 10% of the 44,000 Earths as land, and the rest was water, you could also use wind and wave farms for a lot or most of your energy needs. It still represents almost a fantastically large area, exploring 4,400 Earth's area on some ancient Dyson Sphere would be a campaign and a half. 

[Joerg]

 

3 hours ago, soltakss said:

The thing about Dyson Spheres and the like that I really hate is that they have no sense of realistic scale. Something that has the equivalent of 44,153 earths? Why would someone need something that big? How much of the earth's surface does it take to support 6 billion people? Are we saying that a civilisation needs to support, what, 200 trillion people?

That's about the scale of Ringworld, which admittedly is an evacuation vessel for a commonwealth of inhabited worlds conforming to the Pak norm, only to run wild when the Pak began to specialize to fill ecological niches the majority of Ringworld has no animal life for (excepting the ocean with the planetary maps, access to which appears to have been lost when this development evolved, and which appear to have become accessible again to the builders of the floating cities only after the development had been well on its way and the almost-all-humanoid higher animal life was well established, obviating the re-introduction of such potentially uncontrollable invasive species.

Part of the reason for this size was the need of Pak protectors to keep to themselves and their descendants rather than mingle with those Pak protectors from different genetic lines.

There are different models for sustainable human population density - I recall one (called the lone tiger or similar) advocating oodles of square kilometers per individual. If you have a society that has beaten old age, with each individual a lord over their own domain, this amount of area might be realistic.

Owning such a demesne doesn't mean that humans won't still gather in bigger social entities than their lonesome manor, but in this hyper-advanced technological civilisation you might well expect the comforts of an absolutist ruler for each citizen.

There might be significant elements of non-citizen inhabitants on such a construct, too - lower castes, servitor races, AI drones, pick your choice. In fact, a society quite similar to the original Pak protector society of Ringworld when it started evacuating the galactic core region.

On ‎12‎.‎05‎.‎2017 at 8:02 PM, clarence said:

Haha, well, I realized that reading about distant cultures, whether backward or forward in time, is surprisingly similar. Many historical cultures are so different from our that they just as well could have been on a different planet. Or even alien. Add technology to that and it can get quite interesting : )

I found that if I want to have earth-analogous cultures, it is best to have humans involved in with extremes of transhumanism. I am still not quite decided which organisation would provide control and shelter for these reservates, though - there are contact interfaces where well-briefed visitors may interact with well-briefed border-walkers from within the reservate.

For the overarching organisation I am imagining a couple of very advanced but thoroughly different cultures cooperating to maintain security and

 

I like to create different sets of values for my alien sapients, very much depending on their roles in their original habitat. An apex predator species might resemble the Kzinti, or the Gloranthan Uz. I like to saddle even oxygen-breathing, M-class-world colonizing species to bring their own atmospheric preferences along. One of my earliest ventures into designing planetary species (dating back before my discovery of roleplaying games) included a species inhabiting planets that ended up in stable orbits around a blue giant, with an significant percentage of ozone in the atmosphere due to the high level of ultraviolet radiation reaching down to the bottom of the atmosphere. I don't recall defining much more about these folks other than their general shape (roughly humanoid (bipedal, two arms), endo-skeleton, wide ellipsoid heads with roughly equidistant eyes and other perception organs around the rim) and the kinds of ships they used, or their alliances and conflicts with various groups of humans in the region, but that's ok for a teenage stab at thinking up an alien race. I'm still planning on using these, one of these days.

[Atgxtg]

4 hours ago, dragoner said:

 escape velocity might be nightmarish though

Escape velocity is not all that much of a real factor though. No real ships do it all at once. Besides, I would think that any culture sufficiently advanced enough to make a Dyson Sphere would have (big) space elevators. 

Edited May 13, 2017 by Atgxtg

[Atgxtg]

4 hours ago, soltakss said:

The thing about Dyson Spheres and the like that I really hate is that they have no sense of realistic scale. Something that has the equivalent of 44,153 earths? Why would someone need something that big? How much of the earth's surface does it take to support 6 billion people? Are we saying that a civilisation needs to support, what, 200 trillion people?

Oh, it's realistic-it's just way out of our comfort zone to deal with. That space science in general. As far as the Dyson Sphere goes it's hard to say why someone would need one. I can't understand why someone would need  a smart phone. Want one sure, but need one? It's been said that anyone sufficiency advanced to be able to manufacture a Dyson Sphere wouldn't need to. 

The big perk to a Dyson Sphere is normally considered to be the energy. Since it surrounds a star it captures all of it's emitted energy, which could be used for various (hi-powered) projects-probably stuff long distance space travel, planetary engineering, or some other such big scale project that we're probably too primitive to figure out yet. 

[...]

15 minutes ago, Atgxtg said:

Escape velocity is not all that much of a real factor though. No real ships do it all at once. Besides, I would think that any culture sufficiently advanced enough to make a Dyson Sphere would have (big) space elevators. 

Though for say someone like us, we might be able to land, it would probably trap us there.

Space Elevators are cool (I call them tethers in my games), though even off this small Dyson Sphere, would be enormously long.

[g33k]

One of the things that bothers me about a Dyson "sphere" is the issue of gravity-vs-structure at the poles.

With a "Ringworld" you have it spinning 'round the star in an orbit-approximating fashion; it doesn't need to be built in a manner that either resists flying off into space, or falling into the star (at least, it doesn't have to be strongly-resistant to those forces; depending on how-closely it matches the mechanics of an orbit).

You can set your Dyson sphere spinning, too, so it has a similar "outward" inertia offsetting the stellar gravity... at the equator of the sphere.  But the further you get from the equator, the closer to the poles... the more you just have to build something that just holds stationary over the star.

I've long thought that a "Dyson sphere" should be a "Dyson spindle" ...  

[Joerg]

The point of a Dyson Sphere isn't really to create a contiguous giant area, but to collect most of the energy (and mass) output of the primary. This can be done by swarms of unconnected platforms or sails rather than a solid construction made from unobtainium. You could keep (possibly artificial) planetary bodies in the inner portion of that shell. They needn't be massive, earth size objects either, but could be huge containers of reserve matter (e.g. collected solar wind captured for future fusion plants once the sun peters out).

On the outside, you do want an active guard to capture incoming pieces of stellar matter (providing extra material for platforms, planetoids etc), so you will likely have a couple of electromagnetic bands remaining active rather than the whole spectrum of your primary. Depending on your galactic neighborhood, you might want to have an outward-looking shell actively collecting energy from neighboring suns and distant strong radiation sources, too.

For energy collection to be maximally effective, most of the inner surface would have to be black, possibly a glossy black to reflect some light in order to keep the areas from falling inward.

Such a closed system would collect lots of heat (both potential energy of vibrating and rotating molecules and the low energy electromagnetic radiation emitted by these) - possibly this could be fed back into the sun, enabling fusion processes creating more energetic light, possibly focussed on bodies heated to black radiation in the visible and ultraviolet spectrum, possibly this would be leaked out to the outside of the dome, powering heat-force engines.

If I were to construct a Dyson Sphere as a habitat, I would probably build separate domed areas under crystal domes just like our forebears proposed, each one big enough to hold a continent or so. This swarm of separate units might be tethered together in loops or as a mesh if we want to rely on centripetal force for gravity. Alternatively, one could use planetoids for gravity environments and zero gravity energy collectors in between.

I don't see a significant advantage over an array of donut habitats like in Iain Banks' Culture novels, though.

Ringworld addressed the major drawback of a dyson sphere by hanging an array of shades/PV panels between the surface and its star, thereby creating a semblance of night those sapients from non-tidally locked planets would prefer.

 

Assuming you do build a huge spindle around a primary, with an artificial surface, how thick would you build it? Ringworld suffered from the absence of geology and tectonics after a few millennia of habitation. The artificial elevations of the underlying unobtainium (called Scrith) held maybe a few hundred meters of rock towards the surface, which became subject to erosion from the weather patterns created by the shading panels. The Culture novels by Iain Banks imply a lithosphere inside their donut habitats that rests on molten rock, possibly even allowing volcanism and plate tectonics, at least after temporary heating to the melting point of the minerals.

Raw materials for industry are a problem once all the good matter has been used up to construct the dyson sphere. Even if that civilisation manages an ideal recycling rate, it would still use up some of its matter if it maintains an outside presence. On the other hand that outside presence may bring in replacement or additional resources. There is nothing wrong with moving your dyson sphere away from potential supernovae.

 

Niven's Ringworld setting also has the Puppeteer home system - a Klemperer rosetta of five planets around a fast moving primary fleeing the expanding black hole in the center of the galaxy. While rather wasteful in terms of energy usage, this kind of interstellar architecture would be an alternative to dyson spheres. The sphere or at least ring aspect could be added on an outer orbit, also acting as a shield against incoming objects (which would be a decidedly welcome feature for the paranoid puppeteer society).

[Atgxtg]

3 hours ago, dragoner said:

Though for say someone like us, we might be able to land, it would probably trap us there.

For someone like us, technologically, that's true of just about any planet. Our spacecraft are 90%+ fuel. But if we lived there, we'd probably be able to work something out. Maybe something piggy-backed on an airplane. 

3 hours ago, dragoner said:

Space Elevators are cool (I call them tethers in my games), though even off this small Dyson Sphere, would be enormously long.

Yeah, but if you're able to make a Dyson Sphere, a beanstalk would be easy. But then you might have something more advanced, like a tractor/presser beam or an artificial/anti-gravity device. Even something like a really long ramp could do the job. 

[Joerg]

4 hours ago, dragoner said:

Space Elevators are cool (I call them tethers in my games), though even off this small Dyson Sphere, would be enormously long.

I think that a device to aid overcoming the gravity well is the hallmark of a civilized planet. Of course there will be ships or at least shuttles able to climb out of a planet's gravity well unaided, but only with some sacrifice either in storage capacity or in faster-than-light ability.

A linear accelerator might be an alternative to a space lift or space wheel/bola installation, especially on low gravity bodies like our moon. A hyperloop might be used to build up velocity while inside the gravity well without being pressed to mush if shot up like out of a gauss rifle. There might be cargo deliveries for high-g-tolerating cargo like e.g. ore or basic chemicals that would use such a mode of transport. There might be laser-pushed solar sails involved accelerating vessels out of the gravity well, and the classical reaction drive might see more use than I would be happy about.

Counter-gravity devices or inertial dampeners might take care of the worst effects of the gravity well challenge. A focussed tractor beam might aid a slower vessel take-off.

 

[...]

I'll have to go dig for my notes, as it is from my last computer, but I remember looking at the numbers of escape velocity, because the sphere's diameter is massive, which would also govern the inverse square on gravitation, orbital velocity, and relevant to tether length; they are huge though. Not to say it's isn't possible given a high enough tech level, it just isn't a commonly thought about factor, and this is a small Dyson. Set up to rotate, the lever arm of the tether could launch vehicles at quite a velocity too. 

[Conrad]

21 hours ago, Atgxtg said:

I probably couldn't afford to have one built for me either. It sounds a lot like a Dyson Sphere and Dyson products are pricey.

That's why I wrote "maybe of Precursor design".  Dyson spheres are less likely than Stapledon rings, which is a ring of habitats encircling a star. Dyson got his idea from Olaf Stapledon anyway. 

[Conrad]

19 hours ago, soltakss said:

So, basically a Worldhouse, a dome that covers the planet. That would work in theory, but is an awful lot of work. The effort to cover a whole planet inside a single dome, or strucutre, is enormous. 

I'd create smaller domes, to provide places for habitation/farming/whatever, then perhaps encase several domes under a larger one and repeat if required. 

Sure it is an awful lot of work, which is why I wrote "maybe of Precursor design" because an earlier higher tech civilization would have made it. But you don't have to engage in such a megaproject all at once. Smaller domes would be an excellent way of slowly making a Worldhouse. Over time, as the colony expands, all the domes eventually cover the surface of the world and are linked together.  

Edited May 14, 2017 by Conrad