While we're on the topic of nuclear pollution, "nuclear semiotics" is an interdisciplinary field of research focused on creating a "warning message intended to deter human intrusion at nuclear waste repositories in the far future, within or above the order of magnitude of 10,000 years."

While 10K is a few orders of magnitude greater than 500, I imagine the problems may be similar... if not more extreme.

Source: https://en.wikipedia.org/wiki/Long-time_nuclear_waste_warnin...

I haven't seen the article, but I don't buy it, there's no likely events that will harm Voyager 1 and 2 in that time period, for instance. They could get really unluckly and hit a star/planet, but it's not at all likely. Along a similar vein many of the satellites that we put in graveyard orbits around earth at the end of their useful life will also plausibly last that long, though there is a lot more debris for them to collide with.

We've also certainly... redistributed... many metals and other things around earth. Perhaps "large concentration of iron over what use to be new york" doesn't count, but arguably it should.

> I haven't seen the article, but I don't buy it, there's no likely events that will harm Voyager 1 and 2 in that time period, for instance.

Sure, but nothing will encounter or observe them ever again.

Things we put into heliocentric orbits are likely to be forever, too.

> Along a similar vein many of the satellites that we put in graveyard orbits around earth at the end of their useful life will also plausibly last that long, though there is a lot more debris for them to collide with.

While they won't decay from drag in a few million years, tidal forces and photon pressure become significant over time.

> Sure, but nothing will encounter or observe them ever again.

like trees falling silently in desolate forests?

More than that. There are plenty of atoms and photons and other particles observing those trees, much less for Voyagers.

My favorite weird theory is the "Siluran hypothesis," which states that our industrial revolution was not the first. There are some events in sediment that look like what our industrial revolution will look like. (many millions of years ago, so yes, reptiles)

Yes.

Trying to grasp a time span of one million years feels impossible, in the context of development of culture and technology.

It seems quite unlikely to me that we are the first such development on this rock.

Seems likely to me that we are, given the age of the oldest fossils.