Star Types in Universe

[Straybow]

No, I don't have JTAS.

The way things are going, looks like there may be more L and T types than M. Since they are so hard to detect in distant orbits we just haven't found 'em. After all, galactic rotations say dark matter is several times greater than luminous stars.

The Nemesis speculation based on poorly correlated cyclic impactors involves a dark companion orbiting Sol at up to ¼ LY (16,000 au). Well, it's an idea.

(I thought N, R, and S were nova remnants and hence not main sequence… of course some mnemonics include W, too.)

 

[Malenfant]

R, N, and S are carbon and metal-rich red giant varieties, IIRC.

There are almost certainly more brown dwarfs than there are M stars, but they're not dark matter - there may be many more, but they're also much less massive that most stars, so they can't contribute much to the mass of the galaxies.

 

[Straybow]

Well, no, they can't explain the dark matter mystery. Shoot, even ordinary V dwarfs are dark in that they're too dim to see from great distances. I read something about spiral arms merely being the locations of OB1 clumps (I forget the proper term), with "gaps" between the arms merely lacking the bright star population.

Likewise, many globular clusters are visible to us because a tiny percentage of Type II giants outshine the rest by a factor of 10. Otherwise they'd just be clumps in the halo.

Hmmmm, yes, I had overlooked much of the R-N-S discussion and leapt to a conclusion. On closer reading R-N-S aren't different in terms of mass and luminosity from M, only absorption lines. Who cares if Ss differ from Ms by the presence of Zirconium Oxide instead of Titanium Oxide?

When we're looking at a Traveller stellar population there's no need to include R-N-S, just as I wouldn't bother to include the dozen or so minor variation markers (e, f, etc). But L and T could play a major role making gaps crossable by low jump ships.

 

[Malenfant]

But L and T could play a major role making gaps crossable by low jump ships.

That's basically what I implied in the Brown Dwarf article. Though you'd only be able to refuel from such systems if you had a hydrogen source (eg an icy moon) available - you can't refuel from a brown dwarf.