Re: Planetary Size under 3rdEd?

Nils Jeppe wrote:
> Personally, I don't see what's wrong with just using kilometers (or 
> miles, for the backwards-compatible). In what case could you possibly 
> need a size category for a planet? You want to ram it? It's not like 
> you'll be missing it if you really try.

Size categories are used in multiple ways in Spelljammer; they're on the 
readout of Planetary locators IIRC as well as determining the time it 
takes to escape the gravity well of the object.

> If you really want to make things easier to relate for players, compare 
> stuff to the real world. "This planet is about the size of Jupiter" 
> might be a bit immersion breaking, but I'd say most gamers know enough 
> about space flight / astronomy to know this is one big whopping planet.

I strongly disagree with this, since it DOES break the narrative.  Do 
the characters know just how large a "Large" planet is?  No; you have to 
describe it to players in such a way to instill awe or whatever the 
adventure requires.  For a large planet, start by not describing the 
size.  Say that it keeps getting bigger as they approach it.  Maybe 
something like:

"You expected to enter the gravity well by now, but the planet is still 
getting larger in front of you.  You're still travelling at spelljamming 
speeds, and yet your destination now takes up more of your view than 
(Toril/Oerth/Krynn) does."

This should instill the idea of great size without ever having to use 
measurements, which PCs wouldn't know without at least one full orbit 
and some calculations and some sort of astronomy/planetology skill or 
proficiency.  Once this takes place, the DM can substitute mileage or 
size category to speed gameplay.

Jeff