Originally posted by Kagesh:
I have a few other problems with the Universe/World Development section.
1. In Step 3 - Star Size (page 372), it states that a White Dwarf Star has a Spectral Class of W and a Red Dwarf Star has a SC of M. Then in Step 7 when determining the Habitable Zone, the Table on the top left of page 374 has a row for a White Dwarf with info for SC B,A,F,G,K, and M but no SC of W. Should the White Dwarf even be on this table? Also on this same table the Red Dwarf shares the same row as Main Sequence. Shouldn't the Red Dwarf have it's own row?
Erk. Yes, this is a bit odd, I think....
IIRC, traditionally White dwarfs in Traveller have been given spectral classes, although there's not an awful lot of difference between them (I don't think WD's are given spectral classes of any sort in reality though - they're just referred to as white dwarfs AFAIK). In fact, it's just plain wrong to give a White Dwarf a spectral class of W - that's reserved for things called Wolf-Rayet stars, which are basically one step up from a type O star. Wolf-Rayet stars are so luminous that they're blasting off their outer layers just by shining!
But in Traveller the difference comes from the temperature of the white dwarfs. Here, you could probably just get away with rolling on the Step 4 Spectral Class table if you roll up a White Dwarf, to see what class it is. Ignore the temperature modifiers though - just cross reference the spectral type rolled with the chart on p 374. Previous versions of Traveller have referred to White Dwarfs as "Dx" stars - where "x" is the spectral class (so a White dwarf with a spectral class of A is called a DA star, one with a spectral class of K is a DK star, and so on)
That said, I'm not certain why a DA or DB White Dwarf can't have any habitable orbits, while a DF, DG, DK, and DMs can. If anything, the DK and DM White Dwarfs should be the ones without habitable orbits, and the others should have habitable orbits. So this bit does appear to be wrong.
Though bear in mind that it's stupendously unlikely that you'll have *any* habitable planets around a white dwarf anyway. You will not realistically find anything resembling a 'garden world' like Earth around a White Dwarf.
The Red Dwarf entry on the p374 table probably means you should just look at the 'M' entry on that row - i.e. the only habitable orbit that any Red Dwarf star will have is always going to be Orbit 0.
As an aside, I think the Step 7 table on page 373 is a bit flawed too. I suspect the top row should read "WHITE Dwarf" (red dwarfs are subsumed into Main Sequence Stars, since that's what they are). I think that declaring that the minimum orbit for any White Dwarf is Orbit 0 is a bit optimistic - sure, there may be some captured bodies, or previously existing planets that were orbiting it while it was a Red Giant that have fallen into a lower orbit, but I think it's more likely that at least the first 3 orbits are going to be empty, since usually the star would consume any planets there in its Red Giant phase. I'd suggest using the "Giant" (not Supergiant, though!) line of the table for White Dwarfs too, maybe with a chance for captured worlds in smaller orbits.
