HOW DOES THE HEIFETZ PLANISPHERE WORK?
The “Center of heaven” (for an observer in the Northern Hemisphere) – called the North Ecliptic Pole by astronomers – is marked by the small red-circumferenced green point in the middle of the sky map above. The correspondingly colored large green circle around that point is the ECLIPTIC – we could also call this the “path of the Sun”. It is also the path of the Planets and the Moon, although these circle the Sun in orbits which can diverge somewhat south and north from the ecliptic. Only when the path of the Moon crosses the ecliptic can there be solar or lunar eclipses. The ECLIPTIC is fixed and DOES NOT CHANGE. What has given mankind a great deal of trouble over the millennia is the CELESTIAL EQUATOR which is marked on the sky map above as a large orange point with a red-circumferenced orange circle in its middle. For an observer on Earth, the CIRCLE OF THE CELESTIAL EQUATOR, as opposed to the ecliptic, DOES appear to move its position over time. PRECESSION OF THE SOLSTICES AND THE
