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Could the Earth be an evaporated gas giant planet?

demystifyingscience.com

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Re: Could the Earth be an evaporated gas giant planet?

#81

Earlier quoted context omitted.

I suppose if the anthropic principle is correct that would mean there are many examples, it's just our problem that we are only familiar with one.

Our universe is "fine-tuned" to make it difficult for life on different planets, on different star systems, to find out about and communicate with each other.

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Re: Could the Earth be an evaporated gas giant planet?

#82
post #30

Earlier quoted context omitted.

Not until CGI aliens with non-humanoid body plans become cheaper than masks on human actors.

It's the relatability to the audience that mandates they have human faces. ... because humans can only interpret the facial expressions and emotions of other human faces. Star Trek was never meant to be Sci-fi so much as soap opera in space.

Maybe, but in animated things (like rick and morty) they, occasionally, have aliens that are vaguely essentially anthropomorphic animals and give those expressions.

So it's not entirely.. human. My point being that we can have the expressions of a human face on a non-human face

Re: Could the Earth be an evaporated gas giant planet?

#83
post #44

Earlier quoted context omitted.

Through the atoms of progenitor stars long since gone supernova. Probably neutron stars too! Or also by chance?

I know tidal curves have increase the moons orbit, I’m struggling to think of anything (outside massive collisions) that would cause planets to move closer to their stars, or move to new ones.

If two planets were to pass close enough together, their orbits could become destabilized enough to essentially fling them.

Re: Could the Earth be an evaporated gas giant planet?

#84

Earlier quoted context omitted.

It's the relatability to the audience that mandates they have human faces. ... because humans can only interpret the facial expressions and emotions of other human faces. Star Trek was never meant to be Sci-fi so much as soap opera in space.

Maybe, but in animated things (like rick and morty) they, occasionally, have aliens that are vaguely essentially anthropomorphic animals and give those expressions. So it's not entirely.. human. My point being that we can have the expressions of a human face on a non-human face

> My point being that we can have the expressions of a human face on a non-human face

To bring up the example of the octopus again, you can still get some sense of "expression" like anger etc. when they change their skin colors, without having a relatable face at all.

Or something more common: Dogs wagging their tails, cats pointing their ears, and so on.

Re: Could the Earth be an evaporated gas giant planet?

#85

NO. If solar wind caused a gas layer to evaporate, Earth shouldn't have the atmosphere it does. This planet should be like those surrounding it. Those same solar winds/radiation would have made sure of that. The issue I have with this is the same issue I have with evolution. If conditions were not created to favor life why are we the only planet with any known life & which is perfectly suited to a variety of life? Do…

this whole argument, creationism aside, hinges on earth being the only planet with life, and no one demonstrates that either.

not knowing another is not the same as knowing there's no other.

Re: Could the Earth be an evaporated gas giant planet?

#86
post #43

Earlier quoted context omitted.

It's the relatability to the audience that mandates they have human faces. ... because humans can only interpret the facial expressions and emotions of other human faces. Star Trek was never meant to be Sci-fi so much as soap opera in space.

Farscape did pretty well with having relatable characters played by puppets.

Not just puppets but muppets!

https://muppet.fandom.com/wiki/Farscape

Re: Could the Earth be an evaporated gas giant planet?

#87

Earlier quoted context omitted.

I think you may be mixing up the causation. How probable our universe is, we'll never know (until we can see other universes). We do know that in this universe, life exists. Thus our universe has to be "fine-tuned" for us to exist because we do. As for the universe "favor"ing life, that doesn't really make sense either. I think it's safe to say the universe favors stars, gas giants, black holes but it's pretty hard t…

> Thus our universe has to be "fine-tuned" for us to exist because we do. Because we of course do not exist in this universe because we're fine tuned to exist in it. I can't think of a better way to describe it than the late Douglas Adams did : “This is rather as if you imagine a puddle waking up one morning and thinking, 'This is an interesting world I find myself in — an interesting hole I find myself in — fits me…

That's such a deep thought for a shallow puddle.

Re: Could the Earth be an evaporated gas giant planet?

#88
post #29

Earlier quoted context omitted.

> Is there a succinct explanation of why some terrestial bodies in the solar system (Earth, Titan, Triton, Pluto) have mostly nitrogen atmospheres, but others (Mars, Venus) are mostly carbon dioxide instead? For Earth, the answer is simple: life. In the absence of life, a nitrogen-oxygen atmosphere is thermodynamically unstable. Our best current understanding is that the atmosphere of the early Earth, before life dev…

When solar system planets formed from stellar dust, do we assume that said dust was uniform in composition and merely position, solar dynamics and interplanetary dynamics such as collisions (formation of Moon) led to the differences in chemical composition? For example, it's the outer planets that are gas giants. Venus composition doesn't seem too different from Earth but it's much closer to Sol, so it's more exposed…

> When solar system planets formed from stellar dust, do we assume that said dust was uniform in composition and merely position, solar dynamics and interplanetary dynamics such as collisions (formation of Moon) led to the differences in chemical composition?

That's the simplest assumption.

Re: Could the Earth be an evaporated gas giant planet?

#89

Earlier quoted context omitted.

I love how terse Latin is

That’s mostly because the “to be” gets a folded into the verb.

No, that's not right. Latin has a separate copula --- sum, est, and so on. What gives Latin its terseness is that it supports dropping words implied by context (like the copula in many contexts) and that it's highly inflected, allowing single words to communicate grammatical information that we need word spam to spell out in English.

Re: Could the Earth be an evaporated gas giant planet?

#90

Earlier quoted context omitted.

I’m pretty sure we still have plants, though I admittedly haven’t been out of the house much. A lot of carbon was also captured during the aptly-named Carboniferous Period 360-300 million years ago. Woody plants had just evolved, but microbes that could break them down had not. Thus, coal. An earlier drop in sea levels also caused carbonate (as in limestone, dolomite, and iron ores) to precipitate out. The combinatio…

> Woody plants had just evolved, but microbes that could break them down had not. Thus, coal. Does this mean we’ll never have coal again?

It's not totally impossible for coal to still form, but the conditions are far, far less favorable: microbes get everywhere and the woody plants have a lot less lignin now than they used to, which also makes them easier to decompose. So, yeah, we're pretty got what we got.

Interestingly, this has happened once before. There's a "coal gap" from about 250-230 million years ago during which little-to-no coal was formed in most places. I'm not sure if anyone is sure why; this is right at the time of the P-Tr extinction, so a lot was happening. One theory is that the ligninaceous plants went extinct or other conditions were much less conductive to coal formation.

(FYI: Not a paleontologist or anything like--just a scientist who liked dinos as a kid and remembered some keywords!)

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