CoachThe Earth’s axis is the imaginary line through its poles around which it spins, like a top’s spindle. An orbit is the closed path one heavenly body travels around another — very nearly a circle for the Earth around the Sun, and for the Moon around the Earth.
Examples
Example 43.4 (The system, to scale)
Numbers for the notebook: the Earth is about across; the Moon, about a quarter of that, orbits about away — thirty Earths laid side by side. The Sun is about Earths across and sits million kilometres away. Shrink the Earth to a centimetre marble and the model says: Moon, a peppercorn centimetres away; Sun, a ball over a metre wide, standing more than a hundred metres down the street. Our whole neighborhood is mostly emptiness — as the park scale model of the Solar System already whispered.