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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?

#11

Post by elihu »

perl4ever wrote: post #5
anticensor wrote: post #2

AFAIK Nitrogen in the initial atmosphere rules this out.

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?

According to wikipedia, Venus' atmosphere is about 3.5% nitrogen and its pressure is about 91 atmospheres. So, technically Venus doesn't have a lack of nitrogen (it appears to have about 3 times as much as Earth), it has an extreme abundance of carbon dioxide.

Something interesting I didn't know is that apparently Venus has almost no plain oxygen.

Mars, on the other hand, doesn't have much nitrogen. Perhaps that's attributable to the relative lightness of N2, which would be more prone to float off into space than the somewhat heavier CO2.

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

#12

Post by gnulinux »

elihu wrote: post #11
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?

According to wikipedia, Venus' atmosphere is about 3.5% nitrogen and its pressure is about 91 atmospheres. So, technically Venus doesn't have a lack of nitrogen (it appears to have about 3 times as much as Earth), it has an extreme abundance of carbon dioxide. Something interesting I didn't know is that apparently Venus has almost no plain oxygen. Mars, on the other hand, doesn't have much nitrogen. Perhaps that's at…

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

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

#13

Post by perl4ever »

gnulinux wrote: post #12
elihu wrote: post #11

Earlier quoted context omitted.

According to wikipedia, Venus' atmosphere is about 3.5% nitrogen and its pressure is about 91 atmospheres. So, technically Venus doesn't have a lack of nitrogen (it appears to have about 3 times as much as Earth), it has an extreme abundance of carbon dioxide. Something interesting I didn't know is that apparently Venus has almost no plain oxygen. Mars, on the other hand, doesn't have much nitrogen. Perhaps that's at…

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

Is that a rhetorical question?

I assume it's something to do with: https://en.wikipedia.org/wiki/Limestone

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

#14

Post by dumbfoundded »

hirundo wrote: post #10
mrfusion wrote: post #6

Earlier quoted context omitted.

> It would also tend to support the strong anthropic principle. How does it support that?

The principle is: the universe has been fine-tuned in order to ensure that life arises. 1. The only forms of life that we know about are on a planet with plentiful water and carbon dioxide. 2. Planetary dynamics may favor the production of such planets by the evaporation of gas giants. Ergo, the rules of planetary dynamics appear to favor habitats for life as we know it. This appearance may be just an artifact of our…

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 to say the universe favors life when it's only given us ourselves as an example.

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

#15

Post by bryanrasmussen »

dumbfoundded wrote: post #14
hirundo wrote: post #10

Earlier quoted context omitted.

The principle is: the universe has been fine-tuned in order to ensure that life arises. 1. The only forms of life that we know about are on a planet with plentiful water and carbon dioxide. 2. Planetary dynamics may favor the production of such planets by the evaporation of gas giants. Ergo, the rules of planetary dynamics appear to favor habitats for life as we know it. This appearance may be just an artifact of our…

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 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.

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

#16

Post by mickfaraday »

perl4ever wrote: post #3

"It is not apparent yet that such Rogue planets are regularly traded between star-systems and subsequently participate in serial evaporative events and the proposal may seem like a long shot, but on astronomical time scales the unlikely can become commonplace." It sounds a bit Velikofskian.

Yes, Michael Lund of CalTech updated the Velikofskian hypothesis: https://arxiv.org/pdf/1903.12437.pdf

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

#17

Post by rozab »

gnulinux wrote: post #12
elihu wrote: post #11

Earlier quoted context omitted.

According to wikipedia, Venus' atmosphere is about 3.5% nitrogen and its pressure is about 91 atmospheres. So, technically Venus doesn't have a lack of nitrogen (it appears to have about 3 times as much as Earth), it has an extreme abundance of carbon dioxide. Something interesting I didn't know is that apparently Venus has almost no plain oxygen. Mars, on the other hand, doesn't have much nitrogen. Perhaps that's at…

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

Yep.

https://en.wikipedia.org/wiki/Great_Oxidation_Event

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

#18

Post by mattkrause »

gnulinux wrote: post #12
elihu wrote: post #11

Earlier quoted context omitted.

According to wikipedia, Venus' atmosphere is about 3.5% nitrogen and its pressure is about 91 atmospheres. So, technically Venus doesn't have a lack of nitrogen (it appears to have about 3 times as much as Earth), it has an extreme abundance of carbon dioxide. Something interesting I didn't know is that apparently Venus has almost no plain oxygen. Mars, on the other hand, doesn't have much nitrogen. Perhaps that's at…

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 combination of these effects pushed oxygen levels about 50% above present, allowing very large animals to evolve.

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

#20

Post by dumbfoundded »

bryanrasmussen wrote: post #15
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 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 certainly has to allow for the existence of us because we exist, but I don't think it says much more than that.

It's easy enough to imagine on Earth that conscious life never formed and to imagine such without changing the laws of physics. I don't understand anything about our universe that guarantees the existence of conscious life, let alone guarantees multiple instances.

All we can really say for certain is that our universe allows for us. We really don't know how rare we are.

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