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Yes, even the "extremely" distant galaxy clusters that lie 1-3 billion light years away and are visible in 18+ scopes are, cosmologically speaking, in our backyard.

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Well, I dunno. Three billion light-years is almost a quarter of the way to the edge of the observable universe. If I had to define our cosmic backyard, I'd pick the edge of the Virgo Supercluster as a natural boundary.

Here's one way of looking at that. Within the Virgo Supercluster, galaxy motions relative to the Milky Way are primarily due to local effects. Outside the Supercluster, they're primarily due to cosmic expansion.

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Tony Flanders

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6x15 and 8x32 monoculars
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