A shadow is an absence of light
yet to make one
you need a source of light
you also need an opaque object
of which the shape of the shadow will be formed
You need a surface onto which the shadow is projected.
A shadow appears when light from a source is obstructed by an object yet shadows do not occupy "space"
Shadows are mostly black
but can be coloured under certain specific circumstances.
An object can form more than one shadow
if more than one light source plays upon the object.
A shadow is a virtual image of a real thing
which science says can move by itself
yet they are not "living"
they appear to flicker
but this can be caused by the light source flickering.
There are shadows on the moon - created by the moon itself.
Pure water - with no suspended particles in it
casts no shadow.
Light casts shadows - yet a flame won't.
Glass casts only a faint shadow.
Air can bend light away from its forward direction
and so create a shadow.
Aeroplanes cast shadows
but only when they're close to the ground.
Ironically
once in the air
the shadow is lost under the light source which made the shadow in the first place.
Shadows are fascinating!
