The analemma

Photograph the Sun at the same clock time every day for a year and it traces a tall, lopsided figure eight. That shape is the analemma, and Solmanac is built around it.

The 2026 analemma at mean noon, facing south from the Northern Hemisphere, drawn at true scale: 6.3 times taller than it is wide. Explore it on the figure.

Up and down: the tilt

Earth’s axis is tilted 23.4°, so through the year the noon Sun climbs to 23.4° north of the celestial equator at the June Solstice and sinks to 23.4° south at the December Solstice. That sets the analemma’s height: 46.9° from top to bottom.

Side to side: the equation of time

At the same clock time each day, the Sun is not quite in the same place east to west. When it runs early it is already past the meridian, to the west; when it runs late it has not reached it. That gap is the equation of time, and it sets the width: about 7.4° in all, the Sun reaching furthest west at Great Earlysun in early November and furthest east at Great Latesun in mid-February.

Look closely and the curve’s furthest points come a day or two away from Earlysun and Latesun. Those moments are measured in minutes on the clock; the figure is drawn in angles on the sky, and the same number of minutes covers a little less sky the further the Sun is from the celestial equator.

Why the loops differ

The equation of time has two causes, Earth’s elliptical orbit and its tilted axis. In the northern winter they push the same way, because Earth is closest to the Sun and moving fastest in early January. In summer they partly cancel. So the winter loop is much fuller than the summer one.

Where it crosses itself

The two loops meet at a single point, about 9° north of the equator. The Sun passes through it twice a year, heading north in mid-April and south in late August, and on those two days it stands in the same spot at the same clock time. Solmanac calls them the Northbound and Southbound Echosun.

Which way up

Seen from the Northern Hemisphere facing south, June is at the top and the early Sun is to the right. From the Southern Hemisphere, facing north, the figure appears turned over: December at the top and the early Sun to the left. Neither is the right way up. Its tilt in the sky depends on your latitude and the time of day you choose.