Work of our members

Sphere sundial for children

The search for a sundial attractive also for children produced this colourful ball sundial.
It is made for a latitude of 52 degrees north, but is quite usable in all of The Netherlands.

The sundial is set up so that the letter Z points to the South.
Reading time is an interactive process.

The hour scale is in the equatorial plane and may be rotated about the axis of the earth.
In the photo above, it is set to read local apparent time, with true noon in the south.
But it may just as easily be set to read civil winter or summer time.

The top half of the ball can also turn round the earth’s axis, and is equipped with a shadow caster.
To read time, one turns the hemisphere until the shadow of the shadow caster is as narrow as possible.

The following picture shows the complete assembly.