Everything consists of atoms: air, stones, you, me, grasses and trees. Look around. Everything you see consists of atoms.
Atoms are so small that we cannot see them.
But if we magnify atom that we could see then it would look like this:
There’s gonna be a nucleus which looks like a ball this big (and you show a size of basketball) and heavy like this (and you give a child to hold a stone or anything else that weights 2 or 3 kg).
Sun is very big. It looks much smaller because it’s very far.
In reality if we diminish Earth to the size of a grain of sugar (you can take anything that 1 mm in diameter – a small stone or a crumb of bread) then Sun is gonna be this big (show anything that 10 cm in diameter – ball for example).
Then put a 10 cm ball on the ground and make 5 big steps – 5 meters – and put a grain of sugar on the ground. And say – this is Mercury – the nearest planet to the Sun.
(перевод на русский – см. ниже)
The picture:
Imagine the moon.
Light can travel from Earth to the moon in 1 second.
Moon is very far.
If we will travel to the moon by train it would take 1 year. Fast train in 1 year can go to the moon and back (round trip).
A train can go to the moon faster or slower but light cannot travel faster or slower – it’s always 1 second to the moon and one second from the moon back to Earth.
Alec school 