The Sun Triangle is on Sixth Avenue between 48th and 49th streets installed inside the sunken plaza outside the McGraw-Hill Building at 1221 Avenue of the Americas, New York, New York 10036
The Sun Triangle is a 50-foot sculpture of polished stainless steel set upon a leaning 20-foot stainless steel pole, creating a futuristic look. The sides of the triangle are aligned such that steepest side points to the sun at noon for the summer solstice at an altitude of 73 degrees at solar noon (12:48pm Daylight Saving Time) while the lower side of the triangle points to the winter solstice at an angle of 26 degrees. The upper side and longest side of the triangle points to the the noonday sun on the spring and fall equinoxes.
The plaza also has a reflecting pool, symbolizing the sun, and nine stainless steel spheres, representing the nine planets. A mosaic map of the Earth, done in two projections from the North and South pole is inlaid into the plaza floor northwest of the triangle.
Compare this to the Elmira Sun Triangle designed by Athelstan Spilhaus in 1977
Owner: Beacon Capital Partners
THE SUN TRIANGLE
The sides of the Sun Triangle point to the seasonal position of the sun at solar noon in New York.
The shortest bottom side points to the sun's lowest position on the winter solstice at noon about Dec.21
The longest side points to the sun on the spring and fall equinoxes at noon about March 21 & Sept. 23 The steepest side points to the sun's highest position on the summer solstice at noon about June 21