Celebrated science fiction author Marshall Maresca pointed me to online world-building tools. They are here and here. For good measure here's a real star atlas out to 50 LY.
I'm sure I'm not the only whiner, but doesn't such a tool take some of the fun out of inventing a whole new "known space"? There are several practical upshots for authors and maybe that's the appeal: you might have lots of settings you want to keep track of, and you don't want astute readers catching you in plot holes or continuity problems that you could avoid with a more comprehensive visualization of your universe. Or maybe you could build your story inside a world like Eve, and use that as a promotional vehicle. (Who knows which one would make more money and which would just be a funnel for the core revenue source. That would also presence interesting IP problems, and for all I know probably has already come up.) My concern is that such a program does seem like it risks genericizing science fiction writing to some degree.
I like science fiction or I wouldn't write about it all the time on my blog. But of course, we're just Spaniards writing about two-legged dragons in Patagonia and Baja California as an island of Amazons, and cities of gold in the interior. There's a reality out there waiting for us to find it that will (I hope) obviate all this literature one day, like Las Sergas de Esplandian. Let's build probes! Let's send them to exoplanets! Let's put smaller more chemically sophisticated probes down on Titan and Europa! Now now now!