GEK1506 Heavenly Mathematics & Cultural Astronomy, Tutorial 7

  1. Kepler's 2nd Law implies that the Earth will move faster around perihelion (the point in the orbit where the Earth is closest to the Sun). How can this help explain that the length of the lunations change between about 29.25 and 29.85 days.
  2. What does the orbit of the Moon around the Sun look like?
  3. Why will there not be lunar and solar eclipses every month?
  4. Why are you likely to see more lunar eclipses than solar eclipses?
  5. Why do lunar eclipses last longer than solar eclipses?
  6. What would happen to the number of total and annular solar eclipses if the Moon's distance to the Earth increased?

Helmer Aslaksen
Department of Mathematics
National University of Singapore
helmer.aslaksen@gmail.com