An analogous celestial coordinate system is called right ascension (RA) and declination, with 0° of declination starting at the vernal equinox. The terrestrial system of latitude and longitude makes use of the great circles called meridians.

The Foucault pendulum is a way to demonstrate that Earth is turning At the summer solstice, the Sun is higher in the sky and its rays strike Earth more directly.

great circle — a circle on the surface of a sphere that is the curve of intersection of the sphere with a plane passing through its center. Foucault pendulum — a way to demonstrate that Earth is turning. right ascension — the coordinate for measuring the east-west positions of celestial bodies; the angle measured eastward along the celestial equator from the vernal equinox to the hour circle…. analogous celestial coordinate system — called right ascension (RA) and declination, with 0° of declination starting at the vernal equinox.