Here you will find background information for the science behind Measure Your World.
- Zenithal Circles and Earth's rotation on the June Solstice
- Zenithal Circles and Earth's rotation on the September Equinox
- Rotation Axis, Equatorial Plane, Ecliptic Plane, and Zenithal Plane
- How to use your data
- The Circle
- Construction of a circle
- The number PI
