Okay, temperature is part of the story, but there is a twist to it, Geo.
To tell it well, envision the silver slivers and the cylinder once more, but this time with two kinds of silver slivers: flattened and rounded slivers.
Once the whirlpool in the cylinder subsides a bit, the rounded silver slivers fall into the dead zone and only later do the flattened ones follow. The drag by the rounded slivers is less than the drag for the flattened slivers.
The point to understand is that we have an organized pile of slivers in the center at the bottom of the cylinder. They did not come down willy-nilly but in order based on what they are.
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When Earth and Venus formed in their spatial twirls in the early Solar System, we can envision this as done in an organized manner. There is a selection process taking place which parts of matter slide into the dead zone of the whirlpools first. We have an organized outcome of matter for both planets.
Let me immediately add how there should still be some kind of chaotic element included in this 'organization' -- we are not going for anything perfect here. Yet we do have a certain kind of organization to start out with matter, both for Venus and Earth.
I am ignoring the idea that the entire proto-Solar System could have had a certain level of organization itself already. Rather, I am okay keeping this natural distribution relatively diverse in material distinctions floating everywhere. As such, I want to acknowledge that Venus and Earth may not have a fully identical deposit of the same kinds of material, but I am okay to just think of it that way.
Yet the point is that, while formation is occurring, a certain organization of different materials is happening indeed.
Where both planets would have started with an internal process of gradually reorganizing themselves due to all kinds of circumstances such as temperature, pressure, motion and differences in composition (mass and characteristics), we find that Earth continued this process until it established its current and ongoing conditions.
Venus started that process but did not finish it in the same way as Earth.
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I am just using the data we have today and I make certain parts solid truths, such as Venus having a single day that lasts 2,808 hours and how that always was the case from day one.
While Venus is reorganizing itself internally, the heat of the Sun kicks in and starts to bake this planet. Since it does not rotate all that quickly, the Sun bakes Venus to a crisp like a chicken on a rotisserie rod.
That heat caused the outer layers of Venus' interior to be baked in place. Naturally, all that heat will penetrate deeper layers, too. Nevertheless, this is where the original organization of the planet really matters.
While heat penetrated the planet, layers of silicate, oxygen and water would form a barrier that insulated the interior of the planet. Because Venus had not been able to successfully complete its cycle of internal reorganization, we get a truly different outcome compared to planet Earth.
Venus ended up with two distinct temperature systems. The outer layers (no idea how thick that would be) would absorb the heat of Sun and Greenhouse, and these layers are part of all that we know and suspect about Venus' hot atmosphere and surface.
So, we have a surprise on our hands, since the interior of Venus will be much cooler, frigid perhaps even, since a barrier got established that did not conduct heat toward the interior. This planet got baked, literally. But unlike the rotisserie chicken that is made of meat and bones, we have a striated reality in which (for certain) we bump as some point into poor conductivity. A barrier is more logical than not having that barrier be present.
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There is another surprise, because the specific materials could have (easily) been such that geodetic features would exist in the interior of Venus. We can discuss a hollow to Venus.
Again, this is not one perfect geode, crystals and all, of a humongous large inner cavity, but rather a mix and match of interior spaces, all based on the variety of materials that are found in that interior setting. We need to think in specifics and not in general ideas. Yes, certain geodes will be large.
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One more surprise awaits us because this setup would make it possible for Life to be present if this is indeed the story that correctly describes what happened to Venus. It would not be Life on the surface, and also not anywhere until the conduction barrier is reached and crossed. Yet underneath the barrier, all ingredients for Life would likely be present.
That was fun, Geo.
What I found of interest and that I used for this model is:
- One day equals 117 Earth days
- Early divergence from Earth in evolution
- No mantle degassing, meaning an early shutdown of major magnetism, and therefore still found in abundance in the interior
- Craters in pristine condition
- No plate tectonics
- Suspected of having heat buildup and a potential recycling of the crust as result
Other fun parts I imagined (don't take this too serious): If there had been a moon or moons for Venus, they may have drifted off to Jupiter or perhaps that is how we got our moon. Just a fun thought.
