Celestial Sphere Activities

Sun's Movement Activities

• The celestial sphere can determine and track the sun's pattern anywhere on Earth. The white circle on the celestial sphere is called the ecliptic--the yearly path of the sun. The yellow circle is the daily path of the sun. The daily path is the motion of this circle on the ecliptic as the Earth rotates. Change the date to see how the sun moves and what its exact location would be on that date. Change the location to the equator or the poles for more solar locations.

Equinox Activities

• By changing the date of the celestial sphere to the vernal or autumnal equinox, the sun's rising and setting angles, called azimuths, can be determined. On the vernal equinox, the rising azimuth is 90 degrees. The sun will rise toward the north at lower azimuths in upcoming days. Other activities could correspond to the autumnal equinox, determining the azimuths for that day.

Solstice Activities

• Compare the equinox readings to the summer and winter solstice readings. The celestial sphere determines the time the sun rises on the solstices from anywhere on Earth. It also determines how the sun is above the horizon for a particular latitude degree.

Climate Activities

• Correspond the sun's movement to the climate of a particular geographical area. The sun barely rises and sets at the Arctic Circle, inducing a cold climate. On the other hand, the sun is directly overhead throughout the greater part of the day at the equator, inducing a warm climate. Find readings for the sun's location at different areas and compare the climatic changes at those areas.