According to Vastu Shastra, the ancient Indian architectural and design system, the sun is considered a powerful cosmic energy source. While there is no specific direction for hanging a representation of the sun, there are general guidelines for placing and utilizing natural light in Vastu.
Vastu recommends that the main entrance of a house or building should ideally face east or north, as these directions are associated with the positive energy of the rising sun. Maximizing natural light from these directions is considered beneficial.
If you have a specific decorative representation of the sun, such as a wall hanging or artwork, you can place it in a prominent location where it can be easily seen and admired. However, there is no prescribed direction for hanging the sun in Vastu.
It's important to note that Vastu is a complex and comprehensive system, and the overall energy flow and balance of space are influenced by various factors, including the layout, placement of rooms, and other architectural elements. Consulting with a Vastu expert or consultant can provide personalized guidance based on your specific situation and needs.