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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?

#71

Post by tsimionescu »

three_seagrass wrote: post #32
dumbfoundded wrote: post #14

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…

I mean, you can calculate the probability of an abiogenesis event on pre-biotic Earth (or in our Universe in general), and then run the probability against the known number of solar systems/planets/atoms in the known universe. Whether or not the universe favored life can be interpreted from the resulting improbability and the current results. Stars, gas giants, and black holes are probable.

How could you calculate the probability of an event that we have no idea about? We don't even know for sure that life originated entirely on earth itself - life or some crucial substances required for it could have originated on some other planet with conditions we know nothing about and been brought to earth on some meteorite; or it could have originated in some extreme conditions like a comet tail in close proximity to the sun.

I'm not saying these are necessarily plausible theories, but the fact that we can't discount them tells me enough about how likely we are to be able to calculate a probability for abiogenesis.

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

#72

Post by imtringued »

dumbfoundded wrote: post #60
jjoonathan wrote: post #38

Earlier quoted context omitted.

Isn't this the distinction between the Strong Anthropic Principle and the Weak Anthropic Principle? WAP: we're going to see selection bias in our universe because the preconditions for life must have been satisfied for us to exist within it. SAP: all universes must satisfy the preconditions for life because cogito ergo sum -- the definition of existence requires life to perceive it. I've probably sold SAP short becau…

Yeah, for the most part. The Weak Anthropic Principle from my understanding is simply that intelligent observers are possible. There's no implied likelihood or selection bias. Simply it's possible in our universe. I'd agree with this framing. As for the SAP, I personally find it somewhat meaningless. If that's how you define existence, then you're correct by definition. If you believe a whole universe's existence req…

Well, I offer dwarf fortress as a potential model. When you start a new world in dwarf fortress it will automatically generate a history for that world. There are a lot of games that pretend to be multiplayer but in reality are just filled with bots. Maybe our world is like that and everyone gets their own world.

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

#73

Post by probably_wrong »

anwar343 wrote: post #54

The fact that this paper appeared in April 2019 in a journal called "Acta Prima Aprilia" should give you a clue to how seriously to take it.

Did you just copy pdonis' answer in this same thread word-for-word?

https://news.ycombinator.com/item?id=22894412

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

#74

Post by jacquesm »

probably_wrong wrote: post #73
anwar343 wrote: post #54

The fact that this paper appeared in April 2019 in a journal called "Acta Prima Aprilia" should give you a clue to how seriously to take it.

Did you just copy pdonis' answer in this same thread word-for-word? https://news.ycombinator.com/item?id=22894412

Yes, standard trick of 'green' accounts that want to acquire some karma quickly: repost a good on-topic comment as a top comment. Flagged.

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

#75

Post by azernik »

simcop2387 wrote: post #59
azernik wrote: post #43

Earlier quoted context omitted.

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

I'd agree, but the faces of all the regular characters were very human-esque. Even Pilot's face was puppetted to react vaguely human.

Still a very big departure from humans with masks.

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

#77

Post by saagarjha »

mattkrause wrote: post #18
gnulinux wrote: post #12

Earlier quoted context omitted.

Earth atmosphere is 0.04% CO2. Why does Earth have such little CO2? Is maybe used by life on early Earth?

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?

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

#78

Post by neuronic »

pdonis wrote: post #29
perl4ever wrote: post #5

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? I mean, aside from specifics about each, what's the pattern that you would apply to an arbitrary planet?

> 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 with much more energy absorbed etc.

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

#79

Post by saagarjha »

robbiep wrote: post #45
retpirato wrote: post #35

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…

... up until about 15 years ago we only knew of 9 planets so our sample size was pretty small

And not all of them were even planets, either.

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

#80

Post by saberdancer »

T-hawk wrote: post #36
perl4ever wrote: post #5

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? I mean, aside from specifics about each, what's the pattern that you would apply to an arbitrary planet?

It's not a pattern of ratio or composition, it's a pattern of the quantity of each individual component. The individual quantities then constitute the composition. For CO2, the pattern is temperature. Titan, Triton, Pluto are well below CO2's freezing point so it stays on the surface as ice instead of atmosphere. At these temperatures, nitrogen is the heaviest abundant molecule that remains gaseous, followed by metha…

Titan has enough mass to keep a decent nitrogen based atmosphere as well. It is probably closest to Earth with the exception that methane is a water analogue on Titan.
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