Apparent Sizes and Using Math----- Jan 23, 2006
I. Math review:
-- key: "dependence" problems:
role of constants vs. variables
importance of ratios => meaning of formulae
II. Apparent size
-- more on the Moon: horizon illusion, daytime phases
II. Solar system overview:
-- assume your know the nine Major planets and their order (Pluto?)
-- but did you know: days of the week (7 nearest main bodies)
III. Scale models
-- conversion factor = scale parameter (mind the units!)
-- corresponding ratios are same as in model
-- apparent size as a ratio
IV. Sidereal vs. Synodic
-- sidereal is the view from the stars looking down, synodic is
our view looking up. Which is the more objective view?
-- examples of synodic statements: the Sun is only
in the sky during daytime, the Moon
goes through phases, the stars circle around Polaris
-- examples of sidereal statements: people can be on the lit
or shadowed side of the Earth, the Moon orbits the Earth, the Earth rotates
V. Some history of solar system models
-- importance of "retrograde motion"
-- Ptolemy (100 AD) : geocentric
-- Copernicus (1400 AD) : heliocentric