| Chapter 1: | The New Astronomy |
opacity, like that of the Moon” (Copernicus 20), inferring that all the planets reflect and scatter sunlight just like the Moon. In addition, in an effect most noticeable for Mars, the outermost planets shine brightest by the reflected light of the Sun when they appear on or near the meridian at midnight. They are then opposite the Sun, in the configuration known as Opposition (see figure 1.5). Heliocentric theory attributes these planets'greater apparent brightness at Opposition to their greater proximity to Earth and the shorter distance that sunlight must travel to illuminate
Figure 1.5. Planetary alignments for heliocentric orbits. The position of the Earth at E is shown relative to a Superior Planet (like Mars) in the outer orbit and an Inferior Planet (like Venus) in the inner orbit. Relative to the Sun-Earth direction, a Superior Planet can be at Opposition (O) or Conjunction (C); and an Inferior Planet can be at Inferior Conjunction (IC), Superior Conjunction (SC), Maximum Eastern Elongation (MEE), or Maximum Western Elongation (MWE).
