Is there a stellar type that would make Firefly possible?

[Bizmuth]

The Firefly universe (as I understand it) is a large number of planets orbiting a very large star with a wide habitable zone. Of course, to make that work, the star would also have to be reasonably stable and not emit lethal levels of radiation. Is there a stellar class that could, even in principle, provide that environment?

 

[newjerseyrunner]

Would a Red Giant fit the bill? Other than during their birth and near their death, aren't they fairly stable? They're certainly huge, their radius can be a hundred million miles or more.

 

[Bandersnatch]

Some time ago I made this spreadsheet for main sequence stars:
https://docs.google.com/spreadsheets/d/18dC2D_xyW3tFvWT47kb7Om6hW4YaHpwtUIYtEjvPEEM/edit?usp=sharing
it relates some basic relationships of stellar characteristics and evolution. It's in many ways simplistic, but should give you some idea of what are the scales and directions of tradeoffs between the size of the habitable zone, and the stellar life time.
There could probably be some exotic exemptions to what's in there (e.g. very fast rotators), but I wouldn't bet too much money on those.

The table goes only to something like 5 solar masses, but at that stage the star is already so short-lived, that forming solid planetary crust, let alone evolving a planetary ecosystem, becomes a major stretch.

I've never looked into the lore of Firefly, so I'm not sure what are the orbits of those planets, but you should be able to ascertain whether they fit into the ranges provided in the spreadsheet.

O.k., having just now looked it up, it appears that there are many systems in the 'Verse', most of which consisting of multiple stars (see the poster shown here: http://serenity.popapostle.com/html/episodes/Serenity.htm ) This in effect gives you many habitable zones.

Would a Red Giant fit the bill?

That's already a dying star, which has been significantly changing its size for the past few millions of years. Planets need time and stability to evolve habitable conditions, and the red giant stage doesn't provide much of either.

 

[Bizmuth]

Hmm, I don't see any way to support the number of habitable planets in any of those systems without descending into science fantasy. Oh well.

 

[ohwilleke]

For what it is worth, the universe is so vast that almost anything that is possible, no matter how improbable, probably exists somewhere.

 

[DrStupid]

The Firefly universe (as I understand it) is a large number of planets orbiting a very large star with a wide habitable zone.

If I recall correctly it is a multiple star system with several small stars orbiting a large star. As each star has its own habitable zone, there are much more habitable planets possible than in a single star system and the number could be further increased by haybitable moons of gas giants. In addition there are some terraformed worlds which could be located outside of habitable zones. Something like that is extremely unlikely but not entirely science fantasy.

 

[rootone]

For what it is worth, the universe is so vast that almost anything that is possible, no matter how improbable, probably exists somewhere.

The repository of lost socks must be somewhere.