Here are a few short videos for a good introduction into the topic. Northern and Southern hemispheres are in opposition in regard to Winter/Summer. Try and meditate on the Sun's position at "Noon" during the approximate 3 day period around the Winter solstice. Cheers!
P.S.: Emphasize on the 4th one. 😉
1. https://youtube.com/watch?v=R58VNpY-W9o
2. https://youtube.com/watch?v=adJPV-sz5AI