Sitting on a (very) extended object in space

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A long rigid rod in space has its center of mass at rest relative to the Hubble flow. When traveling to one end of the rod, nearby objects appear to move past at a velocity of v = H_0 L/2, where H_0 is the Hubble constant. Additionally, one can achieve a zero Hubble red-shift by accelerating, which results in relative motion with surrounding objects. This scenario illustrates the effects of cosmic expansion on perception of motion in space. Understanding these dynamics is crucial for grasping the implications of the Hubble flow in cosmology.
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Hi,

I imagine a very long rigid rod in space with length L.

I assume that the center of mass of the rod will be at rest with respect to the Hubble flow - is that right?

If I travel to one of the ends of the rod will I now see nearby objects that are moving with the Hubble flow move past me parallel to the rod with a velocity v = H_0 L/2 where H_0 is the Hubble constant?

John
 
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You can also do this by accelerating so the Hubble red-shift for some distant object is zero. Then it comes as no surprise that you are moving with respect to the objects around you.
 

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