Is it possible to be completely still in space?

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Motion in space is inherently relative, making it impossible to be completely still without a defined frame of reference. While the cosmic microwave background (CMB) can be used to measure velocities, it does not provide an absolute reference frame. The concept of an "absolute reference frame" is questioned, as no such frame exists that is deemed special by the laws of physics. Therefore, any motion must be understood in relation to other objects or frames. Ultimately, complete stillness in space is unattainable due to the nature of motion itself.
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So we are on a rotating planet, which also hurdles through space orbiting the sun, which also is hurdling through space orbiting the center of the galaxy. Is it possible to be motionless in space?
 
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lundyjb said:
So we are on a rotating planet, which also hurdles through space orbiting the sun, which also is hurdling through space orbiting the center of the galaxy. Is it possible to be motionless in space?

Relative to what? Motion is relative. If you are searching for an absolute frame of reference, there isn't one.
 
If you are searching for an absolute frame of reference, there isn't one.

What about the cosmic microwave background; could that not be considered as an absolute F of R?
 
Endervhar said:
What about the cosmic microwave background; could that not be considered as an absolute F of R?

No, there is not such thing as an absolute frame of reference. You can state the Earth's velocity (or anything else's velocity if you wish) relative to the CMB, but it is not an absolute velocity in any sense.
 
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Endervhar said:
What about the cosmic microwave background; could that not be considered as an absolute F of R?

Ask yourself this. What does "absolute reference frame" mean?
 
Endervhar said:
What about the cosmic microwave background; could that not be considered as an absolute F of R?

The CMB does define a frame of reference, but the laws of physics don't single out that frame of reference as special.
 
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