Solar Paths and Position

"Architecture is the learned game, correct and magnificent, of forms assembled in the light."  - Le Corbusier - 

"We are born of light. The seasons are felt through light. We only know the world as it is evoked by light." - Louis Kahn - 

The importance of light in architecture can not be overstated. Understanding the impact of natural light on architectural space is essential for architects. This understanding includes knowledge of the sun and its position relative to a geographic location. 

Most of us know that the sun rises in the east and sets in the west, but there is more to understand. As the Earth rotates around the sun, it is tilted on an axis. This tilt gives us the seasons. In the northern hemisphere, the longest day is the June solstice, and the shortest day is the December solstice. The opposite is true in the southern hemisphere.

The tilted rotation impacts the position of the sun throughout the year. The image below illustrates the position of the sun in Indianapolis. 

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Some useful terms are illustrated in the following diagram. Altitude is the height of the sun relative to the horizon. In the diagram above, the altitude of the sun is higher at noon on June 21st than December 21st.

Additional useful terms for understanding the sun's positions are illustrated in the diagram below. 

The image below provides values for latitude and longitude around the globe.

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Click here to access a site that allows you to find the longitude and latitude of a city. What are the values for Chicago? Anchorage, Alaska? Cairo, Egypt? Sydney, Australia?

Below is a solar chart for a location in the southern hemisphere. It identifies the position of the sun on March 1st at 10am. 

The following diagram shows the sun paths at 4 different latitudes.

Visit the SunCalC app to see how the sun's path changes depending on the time of year, time of day and location on earth.

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