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Old 17-02-2011, 01:25 PM
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mswhin63 (Malcolm)
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Location: Para Hills, South Australia
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Quote:
Originally Posted by higginsdj View Post
Unless there is something wrong with my math, I calculate that this thing would be at Mag 13.9! H = -8.2 mag and from this m = 13.9 mag

using:

D = 1329/pv^(1/2) * 10^(-0.2*H)

I used Jupiters Diameter and albedo (80000km and 0.52)

m = H + 2.5 Log10(d1^2*d2^2/(px*d3^4))

d1 = distance Sun to body (=15,000)
d2 = distance Observer to body (=15,000)
d3 = distance observer to Sun (=1)
px = 2/3 = the phase integral (ie same as the full moon)

Cheers
I think that will find the math for that during my course, but for planetary system wouldn't brightness vary on chemical makeup of the atmosphere. Looking at Jupiter and the NEB the composition of chemicals produce a low magnitude.

I know it is fairly easy to calculate the luminosity of the sun due to the HR diagram but planets would show a different result. I am only learning so give me a break!
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