Solstice

I have placed a rock in the front of my home so that the summer solstice sun
sets directly on it. I have tried for the last two years to place a another
rock where the winter solstice sun would set. However it has been so
overcast and cloudy these last two years that i was unable to see the exact
location of the sunset. Is there a set formula that will tell me where to
place the rock. I need to know how many degrees South of the summer
solstice does the winter solstice hit.

I appreciate any help on this.

J.J.


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