Planets and Stars: Will Our Sun Orbit Bodies With Greater Gravity?

In summary, the sun will orbit around larger bodies in the universe, but will not have an orbit around objects with greater gravity than it.
  • #1
Destrio
212
0
Since each planet and star has it's own gravity which causes smaller bodies to orbit around them. Will our sun have an orbit around bodies with greater gravity than it?
 
Astronomy news on Phys.org
  • #2
The sun, along with the rest of the solar system, orbits the centre of our galaxy.
 
  • #3
...which again is found orbiting in a cluster.
 
  • #4
..which is most likely a part of a larger cluster of clusters.
 
  • #5
.. and so on:P
 
  • #6
Can it be like that for ever?.
The linear speed of the Sun is higher than that of the Earth. Then the Milkyway travels faster in rotating the cluster ..and so on.. until something (we may not know) reaches the limit of light speed !
 
  • #7
pixel01 said:
The linear speed of the Sun is higher than that of the Earth.

Are you sure this is what you mean?

I understand your point here, but obviously no object can reach the speed of light as this would require an infinite amount of energy according to Relativity. Also keep in mind that speed is relative to the reference frame of the observer, so no object can travel with the speed of light relative to Earth.

Note that when discussing speeds in a cosmic sense, one cannot really use classical terms like km/sec as time is also relative to the speed. If we are to make any sense when using classical terms of velocity, we must at the very least define a fixed reference point in space, as in the case of redshift we assume the Earth to be a stationary point in the Cosmos.
 
  • #8
AppleBite said:
Are you sure this is what you mean?

I understand your point here, but obviously no object can reach the speed of light as this would require an infinite amount of energy according to Relativity. Also keep in mind that speed is relative to the reference frame of the observer, so no object can travel with the speed of light relative to Earth.

Note that when discussing speeds in a cosmic sense, one cannot really use classical terms like km/sec as time is also relative to the speed. If we are to make any sense when using classical terms of velocity, we must at the very least define a fixed reference point in space, as in the case of redshift we assume the Earth to be a stationary point in the Cosmos.

The fact that no object can reach the speed of light is something contradict your case: 'and so on', which seems like an unending sequence.
I find it a little difficult to express my idea just now. But I will come back.
 
  • #9
Destrio said:
Since each planet and star has it's own gravity which causes smaller bodies to orbit around them. Will our sun have an orbit around bodies with greater gravity than it?
Just to clarify - large bodies orbit small bodies too.

The Earth is orbiting the Moon just as the Moon is orbiting the Earth. (They both orbit a point part way between Earth and Moon - it's just that this point happens to be inside the Earth's radius.)
 
  • #10
pixel01 said:
Can it be like that for ever?.
The linear speed of the Sun is higher than that of the Earth. Then the Milkyway travels faster in rotating the cluster ..and so on.. until something (we may not know) reaches the limit of light speed !
There is no correlation between the speeds of bodies orbiting bodies within larger orbiting systems - there's no "progression" of orbital speeds that way. It is simply a factor of the masses and the distances of the objects involved. And there are no objects so massive and so close to each other that their orbits reach the speed of light.

That being said, black holes do have mass enough that objects getting very close to them will approach relativistic speeds, converting into energy as they fall.
 
  • #11
pixel01 said:
The fact that no object can reach the speed of light is something contradict your case: 'and so on', which seems like an unending sequence.
I find it a little difficult to express my idea just now. But I will come back.

I fully understand your question here, and it is quite complex matters we are discussing. The thing is that when I said "and so on" I was referring to super clusters. The question of whether such "magnification" goes on forever depends on the theories of the actual "size" of the Universe, though this is a very bad way of expressing it. If one is a believer of the static model the universe has a finite size, though evidence supports the theory that the Universe is expanding. However, you are correct in that based on the concept of concervation of energy (energy can neither be created nor destroyed) and the equation E=mc^2, the amount of matter/energy in the Universe should be finite so there should be a limit to how great a super(duper:P) cluster can be as it would involve all matter in the Universe as we know it today.

Also, it was correctly noted that increase in magnification when considering larger and larger gravitational systems of stars and galaxies does not necessarily imply increase in relative speed as that would require a fixed point in a cosmos that seems to be expanding.
 

1. What determines the size of a planet's orbit around a star?

The size of a planet's orbit around a star is determined by the balance between the gravitational pull of the star and the planet's own velocity and centrifugal force. The greater the gravitational pull of the star, the smaller the orbit will be, and vice versa.

2. Can a planet orbit multiple stars?

Yes, it is possible for a planet to orbit multiple stars. This is known as a binary or multiple star system. However, the orbit of the planet will be more complicated and may vary depending on the gravitational pull of each star.

3. Will a planet's orbit change if it passes by a star with greater gravity?

Yes, a planet's orbit can be affected by passing by a star with greater gravity. The gravitational pull of the passing star can alter the planet's trajectory, causing its orbit to become more elliptical or even causing it to be ejected from its original orbit.

4. How does the mass of a star affect the orbit of its planets?

The mass of a star has a direct impact on the orbit of its planets. A star with greater mass will have a stronger gravitational pull, resulting in smaller and faster orbits for its planets. On the other hand, a star with lower mass will have a weaker gravitational pull, leading to larger and slower orbits for its planets.

5. Could our sun ever orbit a body with greater gravity?

No, our sun is the most massive object in our solar system and there is currently no known object with greater gravity that it could orbit. However, the gravitational pull of other stars or objects in the universe can affect the sun's trajectory and cause it to move through space.

Similar threads

Replies
6
Views
667
  • Astronomy and Astrophysics
Replies
1
Views
310
  • Astronomy and Astrophysics
Replies
10
Views
375
  • Astronomy and Astrophysics
Replies
24
Views
1K
  • Astronomy and Astrophysics
Replies
3
Views
978
Replies
12
Views
2K
  • Astronomy and Astrophysics
Replies
1
Views
1K
  • Astronomy and Astrophysics
Replies
5
Views
1K
Replies
10
Views
3K
Back
Top