Oumuamua: Solar System Acceleration & Origin Traceability

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Discussion Overview

The discussion centers around the nature of Oumuamua, particularly whether it can be considered a normal asteroid and the implications of an accelerating solar system on its motion and origin. Participants explore the potential acceleration of the solar system and how it relates to Oumuamua's trajectory and perceived acceleration, raising questions about relative motion and the forces at play.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • Some participants question whether Oumuamua is indeed an asteroid, suggesting it may not fit that classification.
  • There is a proposal that if Oumuamua were a normal asteroid, its perceived acceleration could be attributed to the solar system's acceleration.
  • Others argue that any acceleration of the solar system would affect Oumuamua similarly, thus not explaining its anomalous acceleration.
  • One participant suggests that the solar system's acceleration must be equal and opposite to the detected anomaly of Oumuamua, but this is challenged by others who state that gravitational interactions affect all bodies equally.
  • There is a discussion about the difference between acceleration and velocity, with some participants emphasizing that the original question was about acceleration.
  • Some participants express skepticism about the idea of the solar system accelerating without a known cause, while others question the assumption that Oumuamua must be the one accelerating.

Areas of Agreement / Disagreement

Participants do not reach a consensus on whether Oumuamua can be considered a normal asteroid or whether the solar system is accelerating. Multiple competing views remain regarding the implications of acceleration and the nature of Oumuamua's motion.

Contextual Notes

Participants highlight the complexity of distinguishing between acceleration and velocity, and the discussion includes unresolved assumptions about the forces acting on both Oumuamua and the solar system.

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TL;DR
Oumuamua passing through accelerating solar syste.
If Oumuamua was a normal asteroid passing through an accelerating solar system, how fast are we accelerating and could the origin be traced if this were the case?

Edit: Also, if it were to be assumed we simply overtook Oumuamua, can we determine our flight path?
 
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DeckSmeck said:
If Oumuamua was a normal asteroid
it's not an asteroid
passing through an accelerating solar system, how fast are we accelerating
in respect to what ?
and could the origin be traced if this were the case?
origin of Oumuamua ? or the acceleration of the solar system.

Does this help ?
 
hmmm27 said:
it's not an asteroid

in respect to what ?

origin of Oumuamua ? or the acceleration of the solar system.

Does this help ?
If we pretended it was an asteroid without any gassing could the unexpected, perceived acceleration of Oumuamua have been instead, attributed to an accelerating solar system?

I think the rate of acceleration would have to be relative to Oumuamua.

I was hoping in this exercise, it might be possible to figure out the flight path of the solar system and Oumuamua.
 
DeckSmeck said:
If we pretended it was an asteroid without any gassing could the unexpected, perceived acceleration of Oumuamua have been instead, attributed to an accelerating solar system?
So instead of an asteroid-sized object with an anomalous proper acceleration, you want to speculate that everything in the solar system with the exception of this asteroid-sized object has experienced an an identical but opposite proper acceleration due to some unidentified inertial force while the object was unaffected?

No, that is simply too ludicrous a scenario to try to reason from.
 
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The acceleration would have to be equal and opposite to the detected anomaly. So a grand total of <20 metres (not kilometres!) per second, happening only during the closest approach to the Sun, as the hyperbolic orbit swung around, changing direction from somewhere opposite of Lyra to somewhere opposite of Pegasus.

But it wouldn't work as an explanation for its acceleration. The entire solar system as a whole can only accelerate due to gravitational interactions with other stars or gas in the galaxy. These work on ever object in the system equally, including on a passing interstellar rock.
 
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jbriggs444 said:
So instead of an asteroid-sized object with an anomalous proper acceleration, you want to speculate that everything in the solar system with the exception of this asteroid-sized object has experienced an an identical but opposite proper acceleration due to some unidentified inertial force while the object was unaffected?

No, that is simply too ludicrous a scenario to try to reason from.

I think that only the star would need to be moving from some current or earlier force, such as an early event like the big bang. It doesn't have to be that though. I would think if the star is traveling then due to its gravitational force, the other bodies in the system would travel with. That would be true of Oumuamua, as well, but the speed difference is to great to capture that object.

Do you think the solar system is not traveling? Why?
 
Bandersnatch said:
The acceleration would have to be equal and opposite to the detected anomaly. So a grand total of <20 metres (not kilometres!) per second, happening only during the closest approach to the Sun, as the hyperbolic orbit swung around, changing direction from somewhere opposite of Lyra to somewhere opposite of Pegasus.

But it wouldn't work as an explanation for its acceleration. The entire solar system as a whole can only accelerate due to gravitational interactions with other stars or gas in the galaxy. These work on ever object in the system equally, including on a passing interstellar rock.
How so we know the solar system is not traveling? I think that is what you giving in your reasoning.
 
DeckSmeck said:
I think that only the star would need to be moving from some current or earlier force, such as an early event like the big bang.
We were discussing an acceleration. Now you are talking about a velocity. Not at all the same thing.
DeckSmeck said:
Do you think the solar system is not traveling? Why?
It has a non-zero velocity compared to co-moving coordinates. So?

[Co-moving coordinates are coordinates against which the universe as a whole is seen to be isotropic. We can measure the Solar System's co-moving velocity by looking for anisotropies in the Cosmic Microwave Background Radiation].

If you are trying to make the point that we do not know whether it is the Solar System that was moving around Oumuamua instead of Oumuamua passing through the solar system, we all agree with that and consider it completely unremarkable. Velocities are relative. There is no such thing as an absolute velocity.

But the word in your original post was "accelerating", not "moving".
 
DeckSmeck said:
Summary:: Oumuamua passing through accelerating solar syste.

If Oumuamua was a normal asteroid passing through an accelerating solar system, how fast are we accelerating and could the origin be traced if this were the case?

Edit: Also, if it were to be assumed we simply overtook Oumuamua, can we determine our flight path?
Even if we were to grant all your assumptions here, it still doesn't work.

Whatever mechanism might ostensibly be acting to accelerate the solar system will also be acting on Oumuamua in the same way (after all its just a body in the solar system like every other one).

In other words, any external force acting on the solar system will cancel out in regards to Oumuamua, and we can ignore that force when it comes to explaining Oumuamua's motion within the solar system.
 
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jbriggs444 said:
We were discussing an acceleration. Now you are talking about a velocity. Not at all the same thing.

It has a non-zero velocity compared to co-moving coordinates. So?

[Co-moving coordinates are coordinates against which the universe as a whole is seen to be isotropic. We can measure the Solar System's co-moving velocity by looking for anisotropies in the Cosmic Microwave Background Radiation].

If you are trying to make the point that we do not know whether it is the Solar System that was moving around Oumuamua instead of Oumuamua passing through the solar system, we all agree with that and consider it completely unremarkable. Velocities are relative. There is no such thing as an absolute velocity.

But the word in your original post was "accelerating", not "moving".
Yes. I read that they discovered that Oumuamua was accelerating away from the solar system. Do they know that the solar system is not accelerating? I don't offer any explanation for why the solar system could be accelerating but by your incredulous reaction to the proposition that some part or even all of that acceleration might be happening in a frame of reference between the original force and subsequent forces that started our solar system and Oumuamua and all other things moving at velocity or accelerating, that isn't likely that the solar system is accelerating. You seem to suggest that it must be Oumuamua that accelerates. I know you read that, just as I did, however, if you can explain why it must be Oumuamua that accelerates then do so, if you will. Otherwise, I take that since see no reason for the solar system to be accelerating because you know of nothing that can be responsible for it, that this is grounds for dismissing it as ludicrous. In that case, your opinion is noted.
 
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DeckSmeck said:
Yes. I read that they discovered that Oumuamua was accelerating away from the solar system. Do they know that the solar system is not accelerating? I don't offer any explanation for why the solar system could be accelerating but by your incredulous reaction to the proposition that some part or even all of that acceleration might be happening in a frame of reference between the original force and subsequent forces that started our solar system and Oumuamua and all other things moving at velocity or accelerating, that isn't likely that the solar system is accelerating. You seem to suggest that it must be Oumuamua that accelerates. I know you read that, just as I did, however, if you can explain why it must be Oumuamua that accelerates then do so, if you will. Otherwise, I take that since see no reason for the solar system to be accelerating because you know of nothing that can be responsible for it, that this is grounds for dismissing it as ludicrous. In that case, your opinion is noted.
I am not a moderator here, but you seem to be skating pretty close to the edge of a warning for unfounded speculation.
 
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Oh. Where do people speculate about physics because I'm not skating, I swimming?
 
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DeckSmeck said:
Oh. Where do people speculate about physics because I'm not skating, I swimming?
Somewhere else. The mission statement and rules for these forums are here

Note, in particular:
https://www.physicsforums.com/threads/physics-forums-global-guidelines.414380/ said:
Generally, in the forums we do not allow the following:
[...]
  • Personal theories or speculations that go beyond or counter to generally accepted science
If you can dig up a peer reviewed article that discusses a theory where the anomalous relative acceleration of Oumuamua is "explained" by an anomalous proper acceleration of the rest of the solar system excluding Oumuamua, we can discuss it.
 
  • #14
jbriggs444 said:
Somewhere else. The mission statement and rules for these forums are here

Note, in particular:
Thanks for showing me that. I will find some other forums more appropriate.
 
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Thread is closed.
 

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