Star Diameters as a Limit on Jumping

Graham Spearing said:

>Quick question for you all. When determining safe 100 diameter jump distance
>for your ship, how many of you check out whether you are also within the
>stars 100 diameters as per Scouts Book 6 p.42?
>
>It struck me that for many main planets who circle at orbit 0 around dim M
>class stars the 100 diameter thresh hold of the star would be far more
>important than the world's. Thus for each world generated using the more
>detailed stellar information found in 'Scouts' a special calculation of the
>safe jump distance from the star would need to be
>made.
>
>Comments and thoughts . . .

I thought about this a while ago, as I was using Scouts to work out 100
diameter limits from the central star.  This can cause difficulities,
especially for large stars, where the typical habital zone is way within
the 100 diam limit.  I had one world which had to be about 40+ days from
the jump point to me reasonably habitable!

So, thoughts: The 100 diameter rule was originally intended to apply to
planets, coming as it does direct from CT (where stars were just pretty
lights in the sky).  This means that the gravity at the jump point is
0.0025 % of the surface gravity.  Now stars (taking the Sun as a model)
are less dense than planets, so the diameter for a given mass is far
greater.  This means you have to travel *fewer* stellar diameters to
reach a safe jump point.  I put some figures together to come up with a
rule of thumd, and I reckon that you can jump at only *20* stellar
diamters.  Gas Giants turn out to have a similar density (near enuogh for
this sort of rough rule), so I've adjusted the gas giant jump point also.

Of course, this has some sonsequences for increased use of micro jumps
closer to the star, but I think the whole thing works better.  Also, this
*is* only a rule of thumb; if the jump distance depends on gravity, then
it would vary dramatically between small, icy bodies, and large, extra
dense bodies.
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