User blog:Cerne/Update (part 1)

Hello Conworld Wikia, I am back.

It has been a long hiatus – and, yes, an unnecessary one, too – but I am back. As I sit here typing, I find myself wanting to describe what I did all this time. I did that before, several times already, and while it did give me some temporary sense of closure, as soon as I would post a subsequent entry and look back at what I had previously published, none of it mattered anymore. It’s sort of like reinventing yourself every time you do something new. At least that is what it seems like to me. Maybe that is why I keep wanting to describe my hiatae(? – pl. hiatus); I am trying to record each past self because I know they will disappear whenever I try to do or think about the same thing again, or pick up on something I started but have yet to complete.

You know what? No more of that. I’m through with it, and now the only thing that matters is what I’m thinking at the moment. So that’s what I’ll type.

If only it were that simple… OK, I did have a few reasons why I was absent from the Conworld Wikia. Most of them revolved around internet access; basically, I didn’t have access to the internet. But there are multiple linked reasons for that, so – to cut a long story short – I do have access to the internet now. Albeit not in the same way I used to. I use three different PCs in three different ways to do three different things with my conworld material online, if that makes any sense (and no jokes, please; if I didn’t say it, it didn’t happen). I have a laptop with internet access at home and in public, which I can use to read and publish entries, but I don’t like typing extensively on it very often. I have my desktop at home that I have time to type on and that I like to type extensively on, but which no longer has internet access. And then there are whichever desktops I happen to be using in public when I am able and permitted to use them, which have internet access and which I can easily publish stuff with, but which have a restricted time limit. So – long story short – I will use my laptop for reading and sometimes publishing, my desktop at home for typing, and public desktops for both publishing and quick reading. And from now on, I am going to keep my status concerning internet use and availability, as well as PC use, out of my blog entries. If anything changes (and it probably will sooner or later) it won’t be significant enough to take up space in an entry. As long as I get something up, that is all that matters.

Speaking (err…typing) of offline status, I have also thought about the amount of stuff I type about that isn’t actually that much related to my conworld. Stuff like ontological and political philosophy and all that $#!+… I mean, yeah, this is a blog, and somehow my own personal views are going to leak into my conworld material in one form or another. I see that other regular Wikia users have published blog entries about their views since my last entry, and it’s kinda cool; it gives us a chance to learn about each other. Umm…but lengthy regular entries on one’s own personal views, at least when they’re coming from me, may be a bit too much of a waste for a conworld blog. Nothing productive is being done on that front, and for someone who hasn’t even published an article (yeah I know)… It puts me in a bad position. To conclude what I typed in previous entries, I do now have another webspace for generic blog entries about non-conworld-related ideas, opinions, discussions, rants, critiques, and whatnot. You can see it here. There is nothing in it yet, but if I have anything generic and/or un-conworldly to type, it will be in there.

And really, in this blog I am typing about a fictional world of my own imagination. A planet, no less, but a fictional one and no more. If it has any beliefs and philosophies, won’t those be its own? I mean, will they even be anything like the kinds of beliefs and philosophies we have on Earth? Do they need to be? And if not, then how relevant will any beliefs and philosophies that I have be for this blog? What the inhabitants of my conworld think about may be relevant to me, too, but it is not likely to be anything anyone can relate to anywhere other than my conworld itself. In which case, I should be putting it here anyway.

……

(And now we see a period break, indicating a shift in topic, though this time with six periods instead of five… Bah, who cares.)

My conworld itself has gone through a major revamp, and so I have a major – but rudimentary – update to put in this entry. I am going to put it into segments so if some parts are too dry or uninformative then you can skip them. However, the idea is that since so much has been updated, it is almost like a re-invention unto itself. Nothing much has actually changed; there has just been a much-needed overhaul of sorts.

OK…first of all, I am happy to say that I now know what my planet will be made of. After much investigation, experimentation, and reflection, I have decided upon two different compositions for the inner and outer core of the planet. Before I continue, I should share some statistics I found online.

Continental Crust: 2.7 to 3.0 Oceanic Crust: 3.0 to 3.3 Mantle (silicates): 3.3 to 5.7 (increasing with depth?) Outer Core (liquid): 9.9 to 12.2 Inner Core (solid): 12.6 to 13.0

The site I got this from can be found here. Wikipedia has very similar stats, which can be found here. Basically the data on both sites show that density gets higher the further down you go into the planet’s interior. According to that Wikipedia article – as well as a few other sources I found but cannot remember and am too unperturbed to try, Earth’s core has a radius of 1220 km which takes up nearly 1/5 of its total radius at 6378 km. This corresponds roughly with Earth’s mean density of 5.5 g/cc, meaning you could potentially divide [a] planet’s total radius by its mean density to get an estimate of what its core radius is. Of course this would depend on the variability of the density of the crust and mantle; a planet like mercury could have a thin crust with a mean density of 5, just like Earth, but that would mean its radius would be a lot bigger in proportion to the rest of the planet. So instead of the core of such a planet being 1/5 of the total radius, it would be more like 4/5 of that total.

There is a 4 g/cc gap between the mantle and outer core, which seems to indicate where the boundary between rock and metal would be. Depending on what the planet was made of, this gap could make the difference between a dynamic core with a working aesthenosphere and a geologically dead chunk of rock. If you have a big gap, then your planet either has a thin crust and a large solid-iron core or a thick crust and a tiny core made of some Period 5 or 6 metal. The way to know which of these you will have is to determine how variable the layers of your crust and mantle are in terms of density, and that depends on what the planet is made of; planets with rarer and denser metals are most likely to have proportionately thicker crusts because the higher gravitational force of the metal will pull in more rocky material. And since they are more rare than iron, they will be comparatively smaller as well. Iron can pull in a lot of rocky material, too, but creating a working aesthenosphere depends on creating enough friction between the mantle and core to melt the lower part of the mantle. For this to happen, the core must be of a noticeably higher density than the mantle. Otherwise there will be no friction; the planet’s core will get bogged down by all that rock, it will slow down, no heat will be released, and the planet will be dead.

Hence the importance of that gap I brought up.

So what does this mean for me? Well, for starters, my planet’s mean density is only 0.4 grams less dense per cubic centimetre than pure iron. Meaning, if I don’t want a dead planet or one that loses all of its heat within an absurdly short length of time (astronomically speaking), I will need to combine any iron I have with something three times as dense – at least 21 g/cc – just to create an alloy with one of each metal. If I follow the same logic I used three paragraphs ago, the resulting core will probably be 1/7th of the entire radius. It will be somewhere between 550 km and 600 km.

What I found interesting was that Earth’s inner core has a density of 13 g/cc, meaning there is much more than just iron and nickel inside it. Wikipedia and various other sources say that much of the inner core is composed of gold; with a density of 19 g/cc, gold could definitely help to bring core density up from 7.874 g/cc (yeah I have it memorized by now). My planet has a mean density of 7.452 g/cc, about 2 grams higher than Earth’s 5.515 g/cc, meaning I would need to bring the density of my planet’s core up to at least 2 grams higher than that of Earth if I wanted the same kind of geologic activity that we get on Earth. Simply adding a higher ratio of what Earth already has could allow me to do that.

So essentially I was left with three choices: 1) give my planet the same absolute density and risk more rapid and continuous heat loss through the mantle and crust in relation to Earth; 2) give my planet the same relative density and settle with the same kind of tectonic activity Earth has; or 3) give my planet a much higher density and have the kind of rigid jig-saw topography I originally wanted, albeit with lower mountains and not so many of them.

Of course I chose the third option. Which was more difficult to substantiate, but this revelation about Earth’s core density meant I could not only add other metals that were much denser than iron and nickel, I could also add more of them. So I settled with a mish-mash of Platinum Group metals and gold. The Platinum Group attracted me because they were chemically similar to iron and nickel so if I wanted something to build up density then this group would be the best choice. And gold…well, it happens to be the most conductive to electricity and Earth already has a lot of it, so why not?

Yes, I am aware these metals are all quite rare; both osmium and iridium make up two of the rarest elements in the universe as well as two of the heaviest, and platinum – which makes up a third of my planet’s core – is the third heaviest. I have taken all of this into account. Trust me. The premise for this planet was that of something nearly half the size of Earth but with only a fraction of the gravity taken off, as opposed to a lot more if the planet had been similar in composition to Earth, so it needed to be much denser than Earth in order for this to work. Call it unlikely. Call it unrealistic. Call it improbable. I don’t care. I needed something improbable, as long as it wasn’t implausible. Some stars could still produce very dense elements if they were massive enough…imagine several white supergiants going off simultaneously, then wait a few billion years and see what you end up with. I dunno, don’t stars get more massive when they form closer to the center of a galaxy? The point is, if these heavier elements exist in some quantity on Earth, they could exist in greater quantities on another planet.

Also consider absolute size: my planet may have more platinum relative to the size of its core than Earth does, but its core is still much smaller than that of Earth. So it may actually have around the same amount that Earth has overall. Or maybe not.

If it will make the skeptics feel better, most of my planet’s core will still be made of iron and nickel (for reference, the alloy of iron and nickel being mentioned here is called “Nife” from the atomic symbol for iron and nickel). I was going to use cobalt, but upon further research I learned that iron is the next element a star will burn after hydrogen and helium so it will be the most common of the heavier elements found in the highest concentrations within a typical protoplanetary nebula. So I dropped cobalt. What I do have, in addition to the Platinum Group metals I listed, is a higher percent of nickel; as opposed to the 10% nickel in Earth’s naturally-occurring Nife alloy, my planet will have anywhere between 20% to 40% nickel, depending on how much of the Nife alloy is found in proportion to the other elements I’ve added per unit of measurement.

To summarize, here is what I have for my planet’s inner and outer core, and their corresponding density: Something else I found out is that a terrestrial planet’s magnetic field is created by its liquid outer core, not its solid inner core. Meaning I never needed to use iron for my planet’s inner core as long as I had some in my outer core. Another reason why I went back to iron instead of cobalt was because iron is the more ferromagnetic element; I thought cobalt was the most ferromagnetic element but I was looking at Curie temperatures instead of the level of ferromagnetism when I made that assumption. All this means, however, is that the median created by comparing the densities of multiple metals and combining them together to determine the density of the resulting alloy would be a mere 1 gram less with iron than it would be with cobalt. Combining iron with a Period 5 Platinum metal could give me roughly the same range of densities Earth has in its outer core.
 * Outer core – 60% Nife (4 to 3 parts iron and 2 parts nickel) and 10% each of ruthenium, rhodium, palladium, platinum, and gold. Density at 12.5 g/cc.
 * Inner core – 10% each of ruthenium, rhodium and palladium, 33% each of platinum and gold, and trace amounts (1%) of osmiridium. Density at 17.7 g/cc.

My planet still has much less iron than Earth does, so its magnetic shield may not be as strong, but I am okay with that. Contact with meteorites might be more frequent but hopefully not too much. It will be worth finally being able to explain the disproportionate gravitational pull (greater pull relative to size, I mean).

Or maybe I can have more iron after all… I still have that rather large mean representing (mostly) whatever there is in the mantle giving me those numbers, so could some of that come from iron? And note: I am not suggesting solid iron here. More like particles of iron – iron oxides and such. I am thinking that perhaps my planet’s core had more iron in it during its formation, but then after it started accumulating rock it ejected much of that iron onto its surface via volcanoes. The iron then sank into the planet’s lower mantle where it was recycled and sent back up again to repeat the process. No doubt this same thing also happens on Earth to some extent, but with my planet’s mean average density being a full 2 grams higher than that of Earth, I would think this “iron cycle” would have to operate on a larger scale to get the kinds of results I am noticing when I figure out how this density mean was – or could have been – obtained. If it did.

But would this presence of iron in the mantle increase or decrease heat loss? I am not sure. Much of this is still hypothetical, but as usual I plan on using it until I have a better explanation with more favourable consequences.

……

All of this business concerning the planet’s interior will surely have an effect on its surface topography. Two bits of information I have on this, in regards to a thicker crust, suggest 1) that tectonic plates will be pushed upward instead of sliding over other plates, and 2) that volcanoes will be less prevalent. Obviously there won’t be very many mountain ranges, if any at all. I am not sure what the plate boundaries would look like without any subduction… Maybe there will be some subduction, but not all of the plate will go under… I am imagining a lot of cliffs, plateaus, and canyons on my planet.

Volcanism will still be present, but instead of a series of eruptions over shorter lengths of time there will be many eruptions at the same time followed by longer periods of dormancy. Volcanoes will also only be formed from hotspots since there will be very little plate subduction, BUT volcanism won’t be chaotic the way it is on Venus because the crust will be cooler and therefore more solid. The volcanoes that have already erupted will alleviate tectonic stress by releasing thermal energy gradually until there is another build-up. And when there is another build-up, rather than forming new volcanoes, the same volcanoes that erupted last time may erupt again. The crust won’t slide over the mantle as easily as Earth’s crust does, so many volcanoes may erupt quite frequently before they go dormant. So overall there won’t be as many volcanoes on this planet as there are on Earth. There will only be more eruptions. The entire surface of the planet won’t be “remodeled” every once in a while the way it is on Venus. It will be more like a flat “sauna world” of sorts. Maybe.

……

The effect of water erosion, and consequently the formation of oceans, is something I am still not sure of; I wanted a higher total ratio of water on the surface relative to Earth but I might not get that if erosion of the ocean floor happens at a slower rate, or if continental shelves erode more rapidly than the sea floor does. Oceanic crust is composed primarily of igneous basaltic rock whereas continental crust is composed primarily of sedimentary rock like limestone, hence the difference in density that was shown earlier. The distinct qualities of these two types of rock may affect how quickly and extensively they erode when they come into contact with water, so if I have these flat landmasses being uplifted by thick, rigid tectonic plates moving upward instead of sliding over the mantle, this may or may not affect how the ocean floor is formed and consequently how much water they can hold. It may make the oceans shallower and hence encourage more flooding on land. If any erosion does occur, it may affect the whole topography of an area at roughly around the same time. Ocean floors will be flat and basin-like instead of deep and cavernous. Land will be level and expansive instead of uneven and hilly.

Keeping in mind that throughout much of the planet’s natural history most of the water on its surface will be frozen, at times when it isn’t frozen that water may be left to accumulate over a wider surface area instead of in higher quantities in deeper oceans. If the erosion rate of sedimentary rock is indeed faster than that of igneous rock, that means a more level topography between land and ocean, which in turn means shallower – albeit perhaps wider – oceans.

Then again, the formation of glaciers may also put more pressure on the ground below it and create deep recesses that may fill with water, becoming deeper and deeper…or maybe the water will accumulate elsewhere.

I haven’t really done as much research into this part yet but what I am predicting is an alternation of cold dry plains and warm humid wetland throughout the temperate and tropic zones, then cold dry plains again before everything freezes. The land will be more flat because more of it will be affected by water at the same time. Sea level will change drastically, but more land will be affected by less water than on Earth, if that makes any sense.

If I don’t want my planet to be completely flooded, I may need to add much less water overall. Another thought that came to my mind was that since the continents will be pushed upward, they may create trenches between them that erode and become deep, narrow canals. A lot of water could accumulate here, too. Ironically, when I asked online about what my planet would be like if a higher percent of its internal composition was metallic, I was told I would have a “wading pool world” or something like that. But if my planet has a thicker crust and hence a higher percent of rock to metal, this would be reversed, wouldn’t it? The picture that now comes to my mind is a mixture of deep canals between a jig-saw assortment of small-ish, flat, dry landmasses and one or two giant basin-like seas that aren’t “shallow” per se but still much shallower than the oceans we have on Earth. This is still a guess, though. A (somewhat) educated guess, but still a guess.

For the record, in case readers don’t know, my planet has two moons. They will probably create land tides, but I am not sure yet what effect it will have on the physical geography of the planet’s surface. This might distort my vision of flat low-lying “jigsaw-ish” continents a bit.

……

And now, finally, I want to bring up something I could cover as part of the update on my planet’s life forms, but it has more to do with the physical aspect of the planet so I’ll bring it up here. For a long time while I tried to figure out what the temperature was going to be like on the surface, and how to make the planet cold over the long run but with patches of hot-house periods every few 100,000 years, I had completely overlooked the Carbon-Silicate cycle. Mostly because it is one of those obscure-yet-integral parts of world-building that was out-of-the-way, but partly because I was also looking for more drastic and irregular occurrences that I never bothered to look at simple chemical processes that happen all the time.

I first ran into the Carbon-Silicate cycle on the Epona Project site, and while it did simplify the process a fair bit, it also served as a good introduction. What I learned was that carbon dioxide enters into a cycle whereby it enters into the water cycle, dissolves and turns into an acid during precipitation, then – upon falling to the ground – dissolves rock and turns into limestone. After a while, the limestone sinks into the crust and gets heated up, upon which it gets sent back into the air as carbon dioxide whenever there is volcanic activity. The Epona project used this cycle to substantiate the idea of prolonged glacial periods separated by warming trends that could last millions of years. This was where I got the idea of a permanent ice age for my conworld, albeit the cycle would be in tens of thousands of years and not millions of years. What you would see, instead of all life evolving only during the interglacial period and then dying back to bacteria-like life forms upon the arrival of another glacial period, would be an assortment of life forms that had eventually evolved toward a cold environment on the surface or a subterranean environment fueled by volcanic and geothermal activity but that could survive – and even thrive – in a hot-house environment on the surface whenever there was one. And there would be a variety of new life forms taking up abandoned niches as well. New primitive organisms becoming more specialized alongside ancient biologically advanced organisms becoming more generalized.

Anyway, in Epona Project’s description of the Carbon-Silicate cycle, it mentions that the precipitation part of CO2 into carbonic acid eroding the planet’s crust was dependent on the amount of heat the planet’s surface received from its sun. The more external heat you have, the more CO2 would precipitate into the water cycle and be sent down to the surface where it would weather away at the rock in the crust. The less external heat you have, the more CO2 would stay in the atmosphere as a gas. This in turn would help to heat the surface internally. So it can be a win-win situation if you want warm surface conditions on an otherwise cold planet. Epona’s problem was that its smaller size sped up heat loss through the crust which sped up weathering and eventually both solidified the crust – leading to reduced tectonic activity – and cooled the planet’s interior.

Now, supposing Epona’s core was made of the same type of nickel-iron alloy Earth’s core is made of, I can see this happening. I even brought it up earlier in this entry. My planet’s core will be much smaller, so heat loss shouldn’t be as rapid. The thick crust is still prone to weathering, and particularly since it is so thick, it is even more prone to solidifying than Epona is. But this thickness also slows down volcanic activity, allowing it to build up and lead to less frequent yet more extensive volcanism. My planet’s sun is also cooler, so there will be less external heat reaching the surface and aiding in the conversion of CO2 into carbonic acid.

The biggest deterrent, however, and the whole reason why I first thought this section had more to do with my planet’s life forms than its physical attributes, is carbon consumption. Basically, at the beginning of each warming trend, multitudes of volcanoes erupt all at around the same time. Along with sulphur and iron-rich ash, they emit lots of CO2. Carbon dioxide can be consumed fast enough already by sun-dependent autotrophes, but if you remember an earlier entry in which I brought up a second group of autotrophes that could use radiation from radioactive isotopes to split CO2 molecules, those organisms could also consume a lot of carbon dioxide. They could multiply very quickly, and since they don’t need sunlight, they could take a lot more carbon dioxide out of the air than the photosynthesizing plants would. So much so, in fact, that more than 90% of the carbon dioxide released at the beginning of each warming trend could be removed within 10,000 years.

What would make these organisms that much more efficient at consuming CO2? Well, I am thinking that since this planet will have a lot more radioactive elements than Earth does, some of these radioactive isotopes could be emitted along with all the other stuff volcanoes put into the atmosphere. The aim here is to stop the weathering process early enough, quickly enough, and thoroughly enough, to keep the planet’s crust from solidifying to the extent that it stops its volcanism and tectonic activity altogether. Maybe I can develop this into a useful story arc… The “radiosynthetic” organisms could become the key to preventing the planet from dying out completely and freezing solid…could this work? I dunno, but it is worth a try.

……

This ends my entry. There will be a Part 2 later, sometime within a week, but I am no longer betting on deadlines. The good thing is I got the geology and physical geography stuff out of the way. I want to briefly go through atmosphere in Part 2 but then I will get into biology, evolution, sophontology (is this even a real subject?), society, culture, and whatever else I can remember to add. Also, I would like to do an entry exclusively on topography and physical geography because I did some research on the subject a while ago before my hiatus, and I’ve got some jotnotes and ideas to bring up. And, yes, I am working on my article. I’ve got one more data field to figure out regarding planetary revolution (orbit around a star) and then that’s it. So even though there have been some hurdles to overcome recently, I am still making progress.

Stay tuned for Part 2. And thanks for reading.