The ancients had no telescopes but they were aware of many astronomical phenomena that are observable with the naked eye.
The sphericity of the Earth.
The visibility of different constellations at difference latitudes on Earth and the circumpolarity of some stars.
The confinement of the motion of the Sun, Moon and planets to a band around the ecliptic.
Rapid diurnal westward motion of the Sun with respect to the stars.
Slow annual eastward drift of the Sun along the ecliptic with respect to the stars.
The phases of the Moon, and their correlation with the time of moonrise and moonset.
The occurrence of eclipses, both solar and lunar.
The differences in motion of the inferior and superior planets.
The retrograde motion of the planets and the variation in the speed a planet moves around the sky.
What causes these phenomena?
|[back to the topics page]||[back to astro 201 home page]||[back to astro FAQ home page]||[back to current A201 FAQ home page]|