Given I’m constantly moving through space, and everything else is constantly moving through space, is it fair to say the exact point in space I’m passing through right now may have previously been passed through by other objects, such as those listed in the title? Are exact (maybe what I really mean is “static” or “fixed”?) points in space even a valid notion?
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No not really. Everything is in relation to everything else, there is no “exact point in space” because that phrase implies that “this point” and “that point” are distinguishable without any objects present, which is not the case. You can imagine having a point, and I say “I have moved that point 10 meters up” but there’s nothing else to compare it to, so how do you know which direction I chose as “up”, how far 10 meters is, and other questions, but there isn’t really an answer to those questions.
And that’s not even accounting for the fact that all of space is expanding, each point (in reference to the objects around it) is getting farther away from every other point.
Yes, you are occupying space the Earth was occupying minutes ago (or will be minutes from now) from the point of view of an observer with their location fixed relative to the Sun.
This isn’t a meaningful question because as you suspected, there’s no such thing as an absolute fixed point in space. I’m not saying it’s not a good question, it’s just not one that really makes sense to ask.
Another responder touched on this, but the two main factors indicating the answer is “no” for planets/stars but “probably sometimes” for asteroids are: The vast emptiness of space, and the expansion of space. If you read through my long-winded answer below I’ll wrap it up with a few thought experiments where this could be possible for asteroids or NEOs (Near Earth Objects).
The expansion of space is the less intuitive of the two factors because at a grand scale (think 1 million light years scale+) everything is moving away from everything else. The best way to visualize this is the “raisin bread” example — as a loaf of raisin bread rises and expands in the oven, ALL the raisins are moving away from all the other raisins. Drawing dots on the outside of a ballon then blowing it up is another good visual.
The practical implication of this expansion is that, for the purposes of your question, we can exclude the possibility that we’re passing through space previously occupied by another galaxy. By the time things settled down enough after the big bang to form atoms, then stars, then supernovas, then things like planets and asteroids the clusters of matter had spread out and variegated to the point that they were already too far apart. It’s extremely unlikely for galaxies to pass through the same space — they just keep moving away. All the space in the universe is doing the same; space is the dough / the balloon from the examples.
There ARE notable exceptions to my “galaxies won’t pass through the same space rule” however – sometimes galaxies are close enough that their relative local speeds are greater than the expected expansion. Our milky way and the andromeda galaxy are notable examples – where they are approaching one another at an apparent 100km/sec, whereas we would actually expect them to be moving at apart. Given their current separation of 2.5M light years we would expect them to be moving apart at ~50km/s due to expansion. BUT this is where the scale comes into play — even after this happens, at the rate of 50km/s it would still take Earth 6000 years to reach its nearest neighboring star. During that time both galaxies are still moving, Earth is still rotating, all this non-overlapping movement makes it very unlikely even in a galaxy collision, that Earth would pass through any space previously occupied by something in Andromeda.
Ignoring other galaxies and just looking at nearby stars, Earth takes 250 million years to rotate once around the milky way (about 250km/s), which is so slow the whole galaxy has shifted through space & space has expanded to the point that it’s unlikely for Earth to be passing through the same space other stars & planets have occupied.
Finally, let’s move down to the level of the solar system itself. I think this is our best bet for moving through space previously occupied by a local asteroid or the moon. BUT it depends on the vectors of the other motion – e.g. solar system moving around milky way at 250km/s. We know the plane of rotation in the solar system is not aligned with the rotation of milky way – so we’re flying at 250km/s vertically relative to the rotation of most asteroids & moon. If we the solar system were moving on the same plane as the moon we’d actually have a good shot of passing where the moon was ~30 minutes earlier for short windows during each month, but that’s not the direction the solar system is moving right now (though at some point in our journey around the milky way it might be).
So FINALLY that just leaves us with asteroids or other NEOs near Earth and in a prograde direction of the solar system’s orbit around the milky way. And this certainly happens with some regularity!
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