ELEMENTAL ASTRONOMY,
IN WHICH THE SCIENCE IS CONSIDERED
PRINCIPALLY IN ITS RELATION TO THE EARTH.
THE SEASONS.
Astronomy is the science which treats of the System of the Universe.
The system of which the Earth is a part, is called the Solar System; and is composed of the Sun, the Planets, Satellites, and Comets.
The Sun is the source of light and heat to the whole system, and is the centre of motion, round which all the other bodies revolve from west to east.
The Planets are opaque or dark bodies, which revolve round the Sun at different distances. There are eleven planets, viz. Mercury, Venus, Earth, Mars, Jupiter, Saturn, Herschell, Ceres, Pallas, Juno, and Vesta.
Satellites are opaque bodies moving round the planets, in company with the planets round the Sun. They are generally called moons. There are eighteen Satellites, viz. the Earth has one, Jupiter four, Saturn seven, and Herschell six.