[Traveller_TNE] The Gas Giant in the Habitable Zone Thread

Part of thread: [Traveller_TNE] The Gas Giant in the Habitable Zone Thread · 2 replies ↳ In reply to [Traveller_TNE] The Gas Giant in the Habitable Zone Thread — dedtraveller [Traveller_TNE] Re: The Gas Giant in the Habitable Zone Thread — Evil Dr Ganymede Re: [Traveller_TNE] Re: The Gas Giant in the Habitable Zone Thread — shadow

I was looking something up in TD19 and I caught the following out of the corner of my eye. I don't know if it's of much use. Anyway, someone wrote in asking what the proper way is to compute the seismic stress factor if the subject world is a satellite of a gas giant.
 
Joe Fugate answered that one can generally ignore the effects of the gas giant. Why? Because the gas giant's relatively low density limits its impact to just a few diameters out. But if you want to be sure, use the following formula.
 
M = (DxK) / (NxVx64)
 
M: Seismic effects of gas giant
D: Diameter of gas giant in km
K: Density of gas giant
N: Orbit number of world-moon in question
V: Orbit conversion factor (see below)
 
V = gas giant diameter / world-moon diameter (both in km)
 
When you plug in the numbers for Regina, you get:
M = (240,000 x 0.27) / (55 x (240,000/11,200) x 64) = 0.86
 
M < 1 you can ignore (according to Joe).
 
If we put in Io...
N = Io's orbital radius / Jupiter's radius = 5.9
 
M = (142,984 x 0.24) / (5.9 x (142,984/3,643) x 64) = 2.3
 
So there's certainly more stress. While Jupiter is smaller than Assiniboia (Regina's GG), Io is much closer than Regina is.
 
I make no guarantees of the veracity of this formula (or my math). I'm just passing along the info. =)
 
\_/
DED
TNE @ Yahoo ml Admin