Moon Phase: The Moon's Visible Lighted Surface (page 2)
Design Your Own Experiment
- Determine the phase of the Moon each day during one synodic month (the time between two successive new moons). Draw a calendar with circles for the Moon's appearance in the squares. For each viewing, shade in the dark parts you see on the Moon. Use Table 18.1 to help you know when the Moon is visible. About 3 days before and after the new moon, the Moon is too close to the Sun to view safely. For these days, or when clouds obstruct your view, use the diagrams before and after these dates to interpolate (predict between data points) the times of moonrise and moonset. Colorcode your calendar to distinguish actual observations from interpretations. CAUTION: Never look directly at the Sun. It can damage your eyes.
- Make a table of the exact times of moonrise (when the moon appears to rise above the horizon) and moonset (when the moon appears to sink below the horizon) each day. You may find the information you need in the newspaper, hear it on television weather reports, or find it on the Internet.
- When the amount of illuminated surface is increasing, the Moon is said to be waxing. When decreasing, it is waning. Find out more about the waxing and waning phases and expand your observation chart. For information, see Dinah L. Moche, Astronomy Today (New York: Random House, 1995), p. 40.
Get the Facts
At times part of the Moon's surface is dimly illuminated by earthshine. What is earthshine? During what phase is earthshine most apparent? For information, see Janice VanCleave's Solar Systems (New York: Wiley, 1999), pp. 38–39.
Warning is hereby given that not all Project Ideas are appropriate for all individuals or in all circumstances. Implementation of any Science Project Idea should be undertaken only in appropriate settings and with appropriate parental or other supervision. Reading and following the safety precautions of all materials used in a project is the sole responsibility of each individual. For further information, consult your state’s handbook of Science Safety.