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Build Your Own Human Sundial: The Analemmatic Sun Clock

Sundials grace gardens worldwide, from ornate formal centerpieces to simple decorative plaques. But the analemmatic sun clock—where you become the gnomon (shadow-caster)—offers interactive, seasonally accurate solar time. This guide walks you through creating one using free online tools.

How Analemmatic Clocks Work

Unlike fixed-gnomon dials, analemmatic clocks have a date scale (usually an ellipse) where you stand on the current month. Your shadow then falls on hour markers calibrated for solar time. An outer ring can show Daylight Saving Time. Components can be flush-mounted (mowable), built as stepping stones, embedded in sand or stone, or painted on pavement.

Essential Data and Tools

Coordinates: Get your latitude/longitude via ZipInfo or NOAA.
Free calculators/templates:
- Personal Shadow Clock (kid-friendly)
- Making a Sun Clock (printable template)
- NASA Solar Clock (printable)
- Pacific Science Center templates (West Coast)
- Sundial Hour Line Calculator (IE only)
- Sundial Primer: Excel Sundials (advanced)
- Sundial Primer: Dialing Guides (precalculated charts)
Layout tools: Compass (for magnetic north), string, tape, protractor, marking paint (or flour), stakes, shovel, calculator.
Optional: Digital camera for site planning; snacks for your build crew!

Design Considerations

Scale the project to your space, budget, and helpers. Schools, scouts, and community groups love this STEM activity. Pre-fabricate components (painted stones, custom gnomon, plantings) on workdays before the main build. Most importantly—have fun!