- #1
FunkyDwarf
- 489
- 0
Hey guys,
Quick question:
Assume the planet (from a previous question) is a perfect black body and that the only source of energy is the [neutron] star. Derive an expression for the temperature of the planet as a function of the orbit distance, star temperature and star radius.
Inverse square law (I1/I2)=(d2/d1)^2
I = sT^4 (s = stefan boltzman)
Ok now i know how to work out watts per m^2 at a distance, that's cool, but in terms of temperature do we really need the star radius? I did the following. I worked out the intensity at the planet distance and converted that to a temperature, but that only depended on the intial distance and the orbit distance, not star radius, unless they suppose that the former is the star radius which doesn't make sense unless we treat the source of energy as the centre of the star.
Any thoughts?
Cheers
-G
Quick question:
Homework Statement
Assume the planet (from a previous question) is a perfect black body and that the only source of energy is the [neutron] star. Derive an expression for the temperature of the planet as a function of the orbit distance, star temperature and star radius.
Homework Equations
Inverse square law (I1/I2)=(d2/d1)^2
I = sT^4 (s = stefan boltzman)
The Attempt at a Solution
Ok now i know how to work out watts per m^2 at a distance, that's cool, but in terms of temperature do we really need the star radius? I did the following. I worked out the intensity at the planet distance and converted that to a temperature, but that only depended on the intial distance and the orbit distance, not star radius, unless they suppose that the former is the star radius which doesn't make sense unless we treat the source of energy as the centre of the star.
Any thoughts?
Cheers
-G