(ai) Define the term solar system (ii) List any five components of the solar system (b) Outline any four characteristics of the earth.

Answer Details

(a)(i) Definition of the solar system

The solar system is the system made up of the Sun and all the heavenly bodies, such as the planets, their moons (satellites), asteroids, comets and meteors, that move round (revolve about) the Sun under the influence of the Sun's gravitational pull.

(ii) Five components of the solar system

• The Sun
• The planets (for example Earth, Mars, Jupiter)
• Satellites (moons)
• Asteroids (minor planets)
• Comets
• Meteors and meteoroids

(b) Four characteristics of the earth

• It is the third planet from the Sun and is almost spherical (an oblate spheroid, slightly flattened at the poles and bulging at the equator).
• It is the only planet known to support life, because it has the right temperature, water and an atmosphere containing oxygen.
• It rotates on its axis once in about 24 hours (causing day and night) and revolves round the Sun once in about 365 and a quarter days (causing the seasons).
• It has one natural satellite, the Moon, which revolves round it.
• About 71 per cent of its surface is covered by water and 29 per cent by land.