16

You cannot: the size of a world is so large that, even with an extremely narrow statistical distribution of physical values, you will end up with noticeable differences, which would not emerge on a lab size environment. At most you can scale up the lab environment to the size of a small building, but as you get larger than that, statistics will beat you.


15

I think your best bet is speed, and lots of it. If you look at pictures of Jupiter and Saturn (and, to a lesser extent, Uranus and Neptune), you would notice belts and zones across the surface. On Jupiter, these are especially prominent because the belts (the dark bands, which fall) and the zones (the light bands, which rise) are composed of different ...


13

These gasses you seek will naturally mix, if given the chance. Their unforced steady-state behavior is always a homogeneous mixing. This means that you need something which forces them. - Wikipedia Quite the stark contrast between the air around Almaty, Kazakhstan and the mountains above is it not? This is caused by an inversion layer. A warm layer of ...


7

They would cook. You are asking for 0.3 atmospheres of water vapor. The temperature of water with that equilibrium vapor pressure is nearly 70 degrees Celsius, or 158 Fahrenheit. An unprotected human will not survive that for very long. And the fact that the air is already saturated with water means our natural heat rejection mechanisms won't work. The ...


7

I guess your main concern is not diffusion. The gases have different densities (CH4 0,656 kg/m³, CO2 1.977 kg/m³). So as soon as the barrier is removed between the squares, CO2 starts to flow to the bottom and spread, CH4 goes to the top and spreads. Of course there will be some diffusion and turbulances, but it does not change the fact, that your lifeforms ...


7

Firstly it sounds like you want to do bottom-up worldbuilding, meaning you want to get the basic science straight first. I would recommend worldbuilding YouTuber Artifexian, as he has a series where he starts with constructing the solar system and has currently reached climate mapping. He breaks down the science to a very digestible minimum. For your ...


7

What matters for breathability is the partial pressure of the gas. According to Dalton law $Partial\ Pressure = Total \ Pressure \cdot volume \ fraction$ For Earth $P_{O_2}=1 [bar]\cdot 0.21=0.21 \ bar$ On your planet $P_{O_2}=1.5 [bar] \cdot 0.055=0.08 \ bar$ That's a tad more than the partial pressure in the Death Zone on Mount Everest at the ...


5

Probably breathable but almost certainly dangerous: The recommended 8 hour Ozone exposure is at most 0.1ppm, that's a thousandth of your atmospheric concentration. Given that studies have shown that tiny increases of just 0.001ppm cause notable increases in fatalities this is almost certainly a sizeable problem in a continuous exposure scenario. The other ...


3

I'd like to offer a frame challenge, based in part on your note on straw-man stalemates: Snowflakes are already all but identical Snowflake classification does not have a particularly long history; while the ancients remarked that there were columns and planes, that is about as close a study as anyone was able to make until the 1880s. Now, as it happens, ...


2

For slow projectile, energy loss due to drag is proportional to the velocity of the projectile and to the density of the medium. Density of atmosphere varies linearly with pressure, everything else constant. In this regime, thus, if you increase the pressure you are proportionally increasing the density and the lost energy. For higher velocities drag is ...


2

If a planet or large moon once rotated much faster than it does now, and if it has had a rigid mantle and not been tectonically active since before it slowed down, then the equator could be 100 or 200 miles higher than the poles -- high enough to rise above effectively all the atmosphere. I can't imagine a combination of astronomical forces that would slow ...


2

Similar to the plant Jinx in Larry Niven's "Known Space" books, a planet with a "fossil tidal bulge" could have "ends" -- inner and outer (or East and West, as in the books) poles -- that stick up out of the atmosphere -- this could produce a high density/pressure atmosphere near the horizon zone (twilight zone for an "eyeball" planet of a red dwarf, or ...


2

Well, it'll react with CO2 to form ammonium carbamate, which is highly water soluble. That will help neutralize the oceans (which would otherwise be acidified by the high CO2 levels--good news for carbonate shell forming creatures), and increase bioavailability of carbon and nitrogen for aquatic autotrophs, but it also means you need an explanation for what ...


2

Some interesting inert gases Neon - to have pretty red-orange lightning Helium-3 - infinite energy if there's civilization that develops nuclear fusion. Heavy gases like fluorocarbons or sulfur hexafluoride - while inert, can settle in terrain depressions and cause choking hazard, making exploration interesting. Can be "mined" for use as refrigeration ...


2

Supposing each gas is at one ATM, their diffusion coefficients should be in the 0.1 ~ 0.3 cm2/s range. We can plug that into Flick's second law to find out how fast they diffuse. It can be simplified to this form: $$t = \frac{x^2}{2D}$$ Where $T$ is time, $D$ is the diffusion coefficient, and $x$ is distance. Assuming a general value of 0.2 for all ...


1

Today, we have examples of some radically different breathing environs. The most unique I know of are breathable liquids, made from specific perfluorochemicals; https://en.m.wikipedia.org/wiki/Liquid_breathing Science-wise, there is nothing preventing a planet from being covered in this stuff, although you’re on your own to figure out a natural process that ...


1

The single biggest inhibitor to life you'll find on this planet is the high oxygen count. It's a common mistake that many people make first time out of the gate to try to set the oxygen percentage the same as or close to Earth, and then dial up the pressure. But, it's not the percentage of oxygen that supports life on Earth, it's the volume. We often talk ...


1

I googled a little something - an actual product that exists on Earth. Now, this product uses a halogen lamp to melt ice, and is advertised to be releasing the same kind of light as the sun. Why did I bring this up? It's because a single wavelength of light won't be enough to melt ice. What you want is a mix of many different wavelengths, as shown by the ...


1

What wavelength of radiation would be the best/most power-efficient choice for penetrating the atmosphere and melting the snow? None. You want the radiation to be absorbed by the snow but not by the atmosphere. To get this information, you just need to compare the absorption spectra of air and snow/water, like it is done in the following chart (source) As ...


1

Frame-challenge You are assuming that the relevant variables controlling ice crystallization are thermodynamic variables. While admittedly not an expert in fractals, the relevant variables to control crystal formation are microscopic variables such as the initial rotation, velocity, etc. of the water particles. For a simple example, look at the Ising model....


1

If the temperature is uniform, snow won't form. The only way I can imagine there being n ear-identical snowflakes is for there to be some kind of curse on the world, it's a simulation, or there's some funny-business going on with nano-machines. Maybe with some future-technology it's possible that all of the snowflakes are "made uniform" after their ...


1

Drag equation. https://en.wikipedia.org/wiki/Drag_equation You can use this to calculate the force slowing your projectile (𝐹𝑑): the drag force. Here is the drag equation. $$F_d = 1/2 \rho u^2 C_d A $$ $F_d$ drag force $\rho$ mass density of the atmosphere $u$ velocity of the bullet $A$ area of the bullet $C_d$ drag coefficient of the bullet Here ...


1

Firstly, lift and drag are both linearly proportional to atmospheric density, so at 3 atm, to provide the same lift as a plane on earth you need 1/3 the wing surface area. This can be a mixed blessing: while you wings are smaller and thus less draggy, to achieve a reasonable velocity during cruise the airfoils need to be thinner to reduce pressure drag. ...


1

I have a personal theory that the way to terraform Mars is make it an ice world, like Hoth. While that might not seem like an ideal terraform to some, it provides significant advantages. Mars is prone to long lasting dust storms. It's covered in tiny, sharp, nasty, often electrically charged and sticky dust, similar to what's on the Moon. It's bad for ...


1

The surface water will evaporate to form a pure water-vapor atmosphere giving you the much needed atmospheric pressure you need to maintain liquid state water. Gravity will make sure the water vapor does not escape into space. But the problem here is 1) the temperature(mostly due to distance from nearest star and partially presence of greenhouse gases and ...


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