MadSci Network: Astronomy |
It does change, but not much. The eccentricity of the earth's orbit is only 1.7 percent, with the earth being closest to the sun in January. All things being equal, I would expect the summers in the southern hemisphere to be slightly warmer than those in the northern hemisphere. In reality, differences in the geography of the two hemispheres (much more ocean in the southern hemisphere) will probably have more effect on the climates of the two hemispheres than this small change in distance.
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