How to picture Solar system to a 2 year old

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.

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How to picture the speed of light for a 2 year old child

(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.

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