Analemma earth

This is a plot of the position of the sun at 12:00 noon at en:Greenwich Observatory, England (en:latitude 51.4791 deg north, en:longitude 0) during the year 2006. The horizontal axis is the azimuth angle in degrees (180 degrees is facing south). The vertical axis is the altitude in degrees above the horizon. The first day of each month is shown in black, and the en:solstices and en:equinoxes are shown in green. It can be seen that the equinoxes occur at altitude φ=90 - 51.4791 = 38.5209 degrees, and the solstices occur at φ±ε where ε is the en:axial tilt of the earth, 23.439 degrees.

This plot was constructed using altitude and azimuth data generated by JPL Horizons.