Solstice sunset

As a child we learned "the Sun rises in the east and sets in the west," right? Not always. In fact that's true only two days a year -- the equinoxes (March and September).

The Motions of the Sun Simulator was used to show the apparent motion of the Sun across the sky on the June Solstice. Notice the Sun rises along the northeastern horizon and sets along the northwestern horizon. At Washington, D.C. (38.89° North latitude and 77.03° degrees West longitude) the Sun reaches a maximum altitude of 74.7° above the horizon, the highest maximum altitude all year.

"Motions of the Sun Simulator" set for 21 JUN at 38.8 N latitude.

The following animation shows the Sun's apparent path across the sky on the June Solstice, repeated several times.

Firsthand Observations

I used my iPad mini 6 running the "Theodolite" iOS app to take a time series of images during the evening on 21 June 2026, beginning at 8:00 PM and ending at 8:36 PM (sunset) with an interval of five minutes between shots. The camera was mounted on a tripod facing exactly west. Notice how far north of west the Sun sets.

21 JUN 2026 | 8:00 PM | Facing west.

21 JUN 2026 | 8:05 PM | Facing west.

21 JUN 2026 | 8:10 PM Facing west.

21 JUN 2026| 8:15 PM | Facing west.

21 JUN 2026 | 8:20 PM | Facing west.

21 JUN 2026 | 8:25 PM | Facing west.

21 JUN 2026 | 8:30 PM | Facing west.

21 JUN 2026 | 8:36 PM | Facing west.

The exact position of sunset was obscured by both clouds and the tree line to the west of my vantage point, but it's clear enough the Sun set near the trunk of the tallest tree along the horizon.

By the way, I have no idea what the white orb is that appears in the lower-right corner of most of the sunset images. I assume it's a feature of the "Theodolite" app, but I'm not sure.

Related Resource: Theodolite - a blog post by Walter Sanford

Post update: The mysterious white orbs that appear in my "Theodolite" images are "augmented reality (AR) markers to show the position of the Sun." According to the developer, the fact that the Sun, as shown in my photos, isn't aligned with the AR markers indicates the compass on my iPad mini 6 was a little off. (Source Credit: "Thoedolite" app developer.)

Google AI says "Check if your iPad case has magnetic closures ... , and try removing the case temporarily to see if your accuracy improves." The Apple case I use with my iPad does feature magnetic closures so I will try removing the case. Although that might help reduce magnetic interference, it might not eliminate the problem because the iPad itself has a built-in magnet that is used to attach an Apple Pencil.

All of that being said, the amateur scientist in me thinks it's also possible the "Theodolite" AR might be a little off, especially since I calibrated the Apple iPad compass before using "Theodolite" to photograph the solstice sunset. I'm just saying, multivariate analysis isn't easy.

Copyright © 2026 by Walter Sanford. All rights reserved.