Little is known, but a rough estimate of the average distance between objects in the Oort cloud is 0.2 AU. That is the same as the density of the planets and moons in the inner Solar system (7 objects within 1.5 AU). And it seems to be the standard presumption among astronomers today that this continues throughout interstellar space in the galactic disk.

Interstellar space has gotten more and more full of stuff the more astronomers have looked. I guess that hasn’t peaked yet.

The belts are about at the one third and two third parts of the trip.

I think it was called “Stepping Stones to the Stars.” I’ll have to find my copy of Asimov on Astronomy.

Not so, it would seem.

The Centauri always seemed to me like Czarist-era Russians with ray guns and starships and not just because of the accent Peter Jurasik put on for his role of Ambassador Molari.

Absent an encounter with real-life aliens who speak English with Russian accents, that particular sound seems likely to be all but absent among humans who actually move out from Earth to live in space. Russia, it now seems clear, is in rapid and terminal decline. Excepting, perhaps, its considerable legacy of orbital debris, Russia’s once formidable space presence will be all but gone by mid-century. By the middle of the next century the Russian nation may be gone as well. The Russian culture is founded on being the dominant bully in its neighborhood. That is a role its rapidly declining population can no longer support. As with much else in its history, Russia’s end is not likely to be a good one, whether it be a protracted death by inches or a quick coup de grâce.