Earth and Space

The motion of the Sun

Teaching Guidance for 14-16 PRACTICAL PHYISCS

At noon the Sun is always due south in the northern hemisphere and due north in the southern hemisphere. It appears to make one revolution from noon to noon (except for some minor deviations which are connected with the changing speeds of the Earth’s orbital motion round the Sun).

The stars appear to make about 1° more than one revolution (360°), so the Sun does not move quite so fast. Like the Moon, the Sun lags behind the movement of the star pattern. But you cannot see it doing this because the stars are not visible during the daytime.

The lagging motion of the Moon carries it right round the ecliptic circle through the star pattern in a month. But the lagging motion of the Sun is slower: 1° in a day, all the way round in a year.

The Zodiac is a belt of the celestial path tilted 23½° from the Equator. The Sun’s yearly path (the ecliptic) runs along the middle line of this belt. The paths of the Moon and planets lie within this belt, which is only 15° wide.

Limit Less Campaign

Support our manifesto for change

The IOP wants to support young people to fulfil their potential by doing physics. Please sign the manifesto today so that we can show our politicians there is widespread support for improving equity and inclusion across the education sector.

Sign today