• CanadaPlus@lemmy.sdf.org
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      2 months ago

      I don’t exactly remember now, but the ring-building aliens ran out of space on their local planets, one way or another.

      It would make sense. In the 70’s in particular people though fusion reactors were right around the corner, and were worried about the waste heat from those.

    • homain
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      2 months ago

      it involves the Pierson’s Puppeteers