Gravitational flux in solar system?

In summary: The gravitational forces of the other planets cause the tides because the water is pulled towards the planets in accordance with their masses and the distance between them.
  • #1
jhe1984
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Is it correct to say that as the Earth (or any other planet I guess) gets closer to the Sun during parts of its yearly revolution, that (at incredibly small levels) gravity on Earth gets stronger (weaker?) ?

Basically, if a planet's orbit from one year to the next stays the same, but its distance from the sun changes throughout the year (it does, correct? ), are there extremely minute fluctuations in that planet's gravity?

Thanks!
 
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  • #2
jhe1984 said:
Is it correct to say that as the Earth (or any other planet I guess) gets closer to the Sun during parts of its yearly revolution, that (at incredibly small levels) gravity on Earth gets stronger (weaker?) ?

Not really. But you can say that the tides from the sun get very slightly stronger.

Surface gravity measured at any point on the Earth's surface with a gravimeter will vary slightly with time, due to tides and tidal effects.

See for instance

http://www.Earth'sci.unimelb.edu.au/ES304/MODULES/GRAV/NOTES/tidal.html [Broken]

However, there should be no average change in the Earth's surface gravity due to the proximity of the sun.
 
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  • #3
jhe1984 said:
Is it correct to say that as the Earth (or any other planet I guess) gets closer to the Sun during parts of its yearly revolution, that (at incredibly small levels) gravity on Earth gets stronger (weaker?) ?

Basically, if a planet's orbit from one year to the next stays the same, but its distance from the sun changes throughout the year (it does, correct? ), are there extremely minute fluctuations in that planet's gravity?

Thanks!
The force of the Sun's gravity will be slightly stronger when we're closer to the Sun (we're at perihelion sometime in the first week of January). This isn't the same as saying gravity on Earth gets stronger.

When you're on the daylight side of the Earth, the Sun's gravitational force opposes the Earth's, so the net force would be weaker. When you're on the night side of the Earth, both the the Sun's gravitational force and the Earth's would add together, making the net force stronger.

Hence pervect's answer that the 'tides' from the Sun would be slightly stronger.
 
  • #4
I am having a difficult time trying to compartmentalize how the Sun, even with its incredible mass, could exert any significant gravitational pull on a planet such as Pluto considering a distance of almost 3.6 billion miles. Not to mention the other even smaller objects that are "trapped" if you will, by the Sun's gravitational pull. For those of you that have the mathamatical skills let's try this as it may help my understanding-Let's substitute Earth for Pluto at a distance of 3.6 billion miles. what would be the extent of the tidal pull on the oceans. I would be surprised to find that a calculation would yield as much as an inch. What say ye!
 
  • #5
newtrigger said:
I am having a difficult time trying to compartmentalize how the Sun, even with its incredible mass, could exert any significant gravitational pull on a planet such as Pluto considering a distance of almost 3.6 billion miles. Not to mention the other even smaller objects that are "trapped" if you will, by the Sun's gravitational pull. For those of you that have the mathamatical skills let's try this as it may help my understanding-Let's substitute Earth for Pluto at a distance of 3.6 billion miles. what would be the extent of the tidal pull on the oceans. I would be surprised to find that a calculation would yield as much as an inch. What say ye!

Well, since tidal forces fall of by the cube of distance and Pluto is roughly 40 time further from the Sun than the Earth, The tides would be about
1/164000 of what they are now.
 
  • #6
Janus said:
Well, since tidal forces fall of by the cube of distance and Pluto is roughly 40 time further from the Sun than the Earth, The tides would be about
1/164000 of what they are now.
Lets see ...you probably mean the tides would be 1/64000 what they are now on Earth.
Right Janus?:uhh:
Creator
 
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  • #7
BobG said:
When you're on the daylight side of the Earth, the Sun's gravitational force opposes the Earth's, so the net force would be weaker. When you're on the night side of the Earth, both the the Sun's gravitational force and the Earth's would add together, making the net force stronger.
Well, not really, Bob. This is a common misconception. The tidal force is NOT a result of the change in the direction of the sum of the two gravitational forces. Think about it again. If that were true it would not explain why the water pulls AWAY from Earth on the 'dark' side of Earth just as it bulges away on the sun lit side.
In reality, the Earth is in free fall around the sun along with everything on it. The Earth surface facing the sun is slightly closer to the sun than the center of Earth and so it experiences a greater force as it free falls toward the sun. The Earth surface on opposite side is slightly farther from the sun than the center of Earth and so it 'lags behind' the center as it free falls toward the sun.
Thus both sides bulge.
This (solar) tidal force is a differential force which results from the difference in DISTANCE of each surface from the sun.
Creator:biggrin:
--I guess I should warn you; if I turn out to be particularly clear, you've probably misunderstood what I've said.-- Alan Greenspan
 
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1. What is gravitational flux?

Gravitational flux is a measure of the flow of gravitational force through a given surface. It is a way to quantify the strength of the gravitational field at a particular point.

2. How does gravitational flux vary in the solar system?

Gravitational flux varies throughout the solar system due to the varying masses and distances of the different objects in the system. The closer an object is to a massive body, the stronger the gravitational flux will be.

3. How is gravitational flux related to the orbit of planets?

Gravitational flux is related to the orbit of planets through the force of gravity. The gravitational force between a planet and the sun is what keeps the planet in its orbit, and the strength of this force is reflected in the gravitational flux.

4. What factors affect gravitational flux in the solar system?

The main factors that affect gravitational flux in the solar system are the masses and distances of the objects involved. The larger the mass and the closer the distance, the stronger the gravitational flux will be.

5. How is gravitational flux measured in the solar system?

Gravitational flux can be measured using mathematical equations derived from Newton's Law of Universal Gravitation. Scientists can also use instruments such as gravitational wave detectors to indirectly measure gravitational flux in the solar system.

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