Star System Development / Orbits

[Kpeterson]

Hey there.
I have a few questions in regards to Star System creation and the placement of planets, gas giants, etc. in specific orbits.

(Per step 7):
Red/White Dwarf planets apparently have no minimum orbit, and Orbit 0 is not considered within the corona of the star. Can it be safely assumed that the first astral body must be placed at Orbit 1 or is orbit 0 an accurate placement?

Red Dwarfs also have no listing for a habitable zone (or the listing is 0, that is). Is there no habitable zone (and thus, no Inner Orbits)? Or can habitation occur as close as Orbit 0? Is every astral body in that star system considered to be in an Outer Orbit?

I'm not too versed in Astronomy... is it the basic assumption that the majority of stars in the galaxy (being Red Dwarf, Class M) cannot support habitable planets? Maybe I'm just confused.

 

[tjoneslo]

Correct, orbit 0 is considered a valid orbit for the class M stars. They're the smallest stars, typically less than 100,000km in diameter. (Our sun is about 330,000 km in diameter) and emits less than 0.1% of the light of the sun.

For most M class stars or white dwarves, I'd be tempted to say all the orbits (even orbit 0) are in the outer zone. You can be generous and allow the M Main Sequence stars to have a habitable zone at Orbit 0.

 

[EvilDrGanymede]

This kinda highlights a problem with the "Orbit x" (where x >= 0) system. Especially when you compare that to extrasolar systems known to exist today that apparently have large planets practically hugging the corona of the stars that they orbit (orbiting well within what Trav considers to be 'Orbit 0'.

There's not an awful lot one can do with this, short of ditching the orbit numbering system, placing planets at more randomly generated distances from the star (see 2300AD for an example), and figuring out temperatures from that. But it is something to be aware of at least.

Oh yeah, and our Sun is actually about 1.3 million km in diameter, not 330,000

. Your diameter sounds a bit small for the M stars too, I think they're more like 200,000-300,000 km diameter.

 

[tjoneslo]

Originally posted by Evil Dr Ganymede:
This kinda highlights a problem with the "Orbit x" (where x >= 0) system. Especially when you compare that to extrasolar systems known to exist today that apparently have large planets practically hugging the corona of the stars that they orbit (orbiting well within what Trav considers to be 'Orbit 0'.

The problem is the orbit table is from book six, and assumes all systems are like ours. If you want a more realistic system, use GT:First In. But even that has some demonstrable failures to model known systems.

Or for a completely realistic system, use accrete
http://www.znark.com/create/accrete.html

Oh yeah, and our Sun is actually about 1.3 million km in diameter, not 330,000

. Your diameter sounds a bit small for the M stars too, I think they're more like 200,000-300,000 km diameter.

So much for my ability to convert units on the fly...