(a) Describe the solar system. The solar system is made up of the sun and its nine planets with their satellites. The planets are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto. The sun is at the centre of the system and all the planets revolve round the sun in elliptical orbits. The sun is the source of light and energy for all the planets. The planets shine only by reflected light from the sun, Of the planets, Mercury is the closest and hence the hottest of the planets. It is the smallest planet while the largest planet is Jupiter. Pluto is the farthest from the sun and hence the coldest of the planets. Saturn has a unique feature of three rings.
(b) Characteristics of Planets
(i) Pluto
(a) It is the coldest
(b) It is the farthest
(c) Has the longest orbit round the sun
(d) Has no satellite
(e) Takes 247 years to complete one revolution round the sun.
(ii) Mercury
(i) It is the smallest
(ii) It is the closest to the sun(97,600,000km)
(iii) It is the hottest
(iv) It has no satellite
(v) Does not support life because of heat
(vi) Takes 88 days to revolve round the sun.