The suns actual base

Nov 17, 2020
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If the sun was a planet and it's base was plasma, not hot at all, would the moon cause high and low tide for the plasma?
 
Jun 1, 2020
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If the sun was a planet and it's base was plasma, not hot at all, would the moon cause high and low tide for the plasma?
:) Tides are only due to mass. Hot vs. cold mass is not a consideration. Two bodies (masses) will have gravitational attraction. Space objects are in motion, so gravity has noticeable effects when either one or both are very massive, or they are close. Mercury is very effected for both reasons since it is close to the Sun, and the Sun, by any label, is very massive (330,000x that of Earth, IIRC).

The mass effect is linear, and the distance effect is by the inverse square. IOW, doubling the mass of one will double the force of gravity, but reducing the distance in half will increase gravity 4x.

Given that, tides vary as the inverse cube. So if you cut the distance in half, the tidal forces increase 8x! This is why so many moons that form close to their host planet, or host star, are tidally locked. It is also why asteroids will break into pieces as they get very close to the planet's surface. [see Roche Limit]
 
May 14, 2021
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Just as the sun and moon cause tides on the earth’s oceans and to a lesser extent, the earth/moon system actually causes a tiny tide on the surface of the sun.
A plasma, by definition is very hot. Cool down a plasma, nuclei and electrons would immediately seek one another and form atoms and molecules.
 
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Catastrophe

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We are talking about tides, and thus the effects of Sun and Moon on Earth.

The Sun is much further away than the Moon (which orbits Earth) but much more massive.

Cat :)

P.S. For reference:

Plasma is called the fourth state of matter after solid, liquid, and gas. It is a state of matter in which an ionized substance becomes highly electrically conductive to the point that long-range electric and magnetic fields dominate its behaviour.

Plasma (physics) - Wikipedia
 
May 14, 2021
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I don’t think they’ve actually observed a tide on the sun due to the earth, but, the fact that the sun raises a tide on the earth, they’ve calculated a tiny tide on the sun. I had read some years ago, perhaps in Sky and Telescope magazine that just as the moon’s orbit is receding from the earth, since the sun rotates faster than the earth orbits, it has probably receded from the sun in the last 4 1/2 billion years, perhaps to the tune of about 6 inches, not much anyway. In a 1948 edition of an astronomy textbook, it said that If the earth/moon system would last long enough before the sun goes red giant, once the earth becomes tidally locked to the moon, it would continue to slow down until it would be tidally locked to the sun, and the moon would begin to approach the earth in its orbit until it reached the Roche limit and break up into a Saturn-like ring. But, the sun will have gone red giant kazillions of years before that and the earth/moon will have long vaporized.
 
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Yeah, the greatest orbital change to the Earth will come when the Sun ejects a large portion of its mass to form a planetary nebula. Thus, the swelling of the Sun may not extend all the way to the new outer orbit for Earth, not that the crispy critter difference would be noticeable. :)
 
Jun 15, 2021
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I think that the temperature here will only affect whether the moon will burn out when close to the sun, well, if we imagine that the sun and the Earth have changed places. If the sun is not hot, and the moon revolves around it, then in theory such tides can be, only very tiny, I think a few centimeters, but not meters like the tides on Earth.
The point is also in the mass ratio, and the plasma is much denser than water. True, I think we need to study this phenomenon more in order to talk about it.
 

Catastrophe

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MM :) There are even tiny tides on the Moon, and that is solid:

"Tides on the Moon: Theory and determination of dissipation ...
https://agupubs.onlinelibrary.wiley.com › doi › full


by JG Williams · 2015 · Cited by 66 — Solid body tides on the Moon vary by about ±0.1 m each month. In addition to changes in shape, the Moon's gravity field and orientation in ...
Tidal Potential · ‎Physical Librations · ‎Fits for Dissipation · ‎Future Investigations"

Cat :)

And don't forget the Sun:
Quote
Published: 23 April 2013
Are Planetary Tides on the Sun and the Birthplace of Sunspots Related?
Ilgin Seker , Solar Physics volume 286, pages303–314 (2013)Cite this article
Quote
 
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btw, the sun has increased its luminosity since it’s birth and continues to increase as it ages due to higher density as a result of conversion of hydrogen to helium. As the luminosity increases, the energy received by the earth (and the others) likewise increases. The latest thought I’ve seen, is that temperatures will rise (nothing to do with the current change, too short term) until the entire earth turns to desert, all the water evaporates, and maybe turn into a cooler Venus, about a billion years from now. No life left on Earth. We’ll have moved on somewhere; or no longer in existence.
 
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btw, the sun has increased its luminosity since it’s birth and continues to increase as it ages due to higher density as a result of conversion of hydrogen to helium. As the luminosity increases, the energy received by the earth (and the others) likewise increases. The latest thought I’ve seen, is that temperatures will rise (nothing to do with the current change, too short term) until the entire earth turns to desert, all the water evaporates, and maybe turn into a cooler Venus, about a billion years from now. No life left on Earth. We’ll have moved on somewhere; or no longer in existence.
That is nicely stated, though I would enjoy reading a reference paper on what Earth would suffer in 1 billion years.

Here is a nice graph (Wiki) that demonstrates some of what you stated. Most might think the Sun is getting hotter, associating heat with temperature. But it is the increase in the Sun's radius that is generating more luminosity, which gives us more radiation (heat).

But it's worth remembering that any temperature increase must be taken to the 4th power. Thus the temperature increase from 5620K to today's 5777K (only a 2.7% increase) taken to the 4th power is an increase factor of 1.1165 (~11-1/2%). The radius increase of 15% causes a luminosity increase as to the square. Thus the size increase contributes a factor of 1.3225.

Multiplying both the size and temperature luminosity increases gives us a 48% overall increase. [This seems much higher, admittedly, than values I have seen elsewhere (e.g. 30%). ]

The chart shows that in about 1 billion years, there won't be any temperature increase but the size increase will produce about a 10% increase in luminosity. This assumes Wiki's chart is correct.
 
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Actually, I had seen this on an episode on a science television program some years ago, NOVA or National Geographic, one of them.
 

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