How to Keep a Journal of the Sun's Motion

Place the poster board on a flat table outdoors with a clear view of the sky in all directions. Mark an "X" in the center of the board. Use the carpenter's level to ensure that the table is perfectly level. Add shims under the legs or reposition the table to make it level.

Set the plastic dome on the poster board with its center directly over the X. Trace the rim of the dome onto the poster board. Remove the dome.

Find true north with the compass. Mark the letter "N" just outside the outline of the dome. On the opposite side, mark the letter "S" for south. Do the same for "E" and "W," always keeping the letters outside the outline.

Replace the dome over its tracing. Hold a marker just above the surface of the dome. Move the marker until its shadow falls under the dome. When the shadow of the marker's tip intersects with the center of the X on the board, press the tip against the dome. This mark correlates to the sun's position in the sky.

Make a full day of observations. Check that the weather will be mostly sunny. Erase any practice observations from the dome. Begin just after sunrise. Record the time of sunrise in the journal, and mark your first observation on the dome soon as the sun is high enough. Continue to make observation marks on the dome every couple of hours throughout the day.

Record the time of sunset in the journal. Carefully connect all of the day's observation marks in an arc that sweeps from sunrise to sunset. Note the locations of sunrise and sunset relative to the compass directions, as well as the approximate time and location of the sun's highest point. Record this information in the journal.

Make these observations every day that the weather allows. Use different colored markers for each day of the week. Carefully transcribe all of the data into the journal. In only a few weeks, the seasonal motion of the sun across the sky should become obvious.