Star map of the constellation patterns in the above 'planets in motion' graphic, showing the ecliptic and the celestial equator. The constellation names are shown (in their abbreviated three-letter form) in this image (54 KB) - the full names are listed here. Zodiac constellations are labelled in green and non-zodiac constellations in grey. The significant solar positions marked on the chart apply to the Northern hemisphere and are as follows: VE = Vernal (Spring) Equinox, SS = Summer Solstice, AE = Autumnal Equinox and WS = Winter Solstice. In the night sky, the ecliptic is shaped like a sine wave with its most Northerly point in Gemini (i.e. at the Northern hemisphere summer solstice point) and its most Southerly point in Sagittarius (at the Northern hemisphere winter solstice point). Hence from the Northern hemisphere, Gemini will be the highest zodiac constellation in the sky and Sagittarius will be the lowest zodiac constellation in the sky; the reverse is true for Southern hemisphere (56 KB) observers. For any given location on Earth, the Sun's sinusoidal path through the constellations (brought about by the tilt of the Earth's axis in space) causes the Sun's rising and setting directions on the local horizon to change throughout the year. Hence the length of the local day and night varies throughout the year, giving rise to the seasons. The numbers along the sides of the chart (Right Ascension and Declination) are co-ordinates of celestial longitude and latitude which astronomers use to locate the position of a celestial body in the night sky.

The 'Naked-Eye Planets in Motion' Flash animation is produced by David Colarusso (note that the graphic requires the Shockwave Flash Player plug-in to display correctly).

Copyright  Martin J Powell  November 2005