Open the Floodgates of Urth!
As I mentioned somewhere else, "Additions, Errata, &cetera:
volume III" is taking shape in the magic mirror.
There's a paperback chapter page citation key which should come in handy for some.
Terraforming notes re: Mars/Verthandi, Venus/Skuld, Luna/Lune,
and stellar engineering re: Old Sun (as in real engineering answers to "why insert a black hole into a perfectly good star?") and New Sun (as in real engineering answers to . . . well, you get the idea).
Something about the early neutrino count from the sun . . . still researching this one. Feel free to help if you know anything.
An entry on Kardashev Levels of civilization.
An entry on various Apollos.
And more things of that sort.
=mantis=