A model to demonstrate the precession of the Moon's orbit relative to the ecliptic. It is useful for discussing the conditions necessary for the occurrence of an eclipse.
Due to the oblateness of the Earth, the gravitational force between the Earth and the Sun sets up a couple which causes the Earth's axis of rotation to precess. An adapted globe shows what is meant by...
The redshifted spectrum of galaxies and quasars is due to an expanding universe and can be expressed as the ratio of the scale factor of the present Universe to that of the Universe when the light was emitted. You can think of this as the...
The selective reflection of a specific wavelength of light through a chiral nematic liquid crystal is temperature dependent and forms the basis for LCD thermograms and thermometers.
