"Why is the sky blue?" is the quintessential question
asked by a child and flubbed by a parent

throughout the ages, parents confronted with this
question could do little but babble in befuddlement

but today's 21st-century parents have a place they
can turn -

to the internet and Google, YouTube, NASA, and the
History Channel

NASA, for example, provides this illustration



and adds,

Sunlight reaches Earth's atmosphere and is scattered in all directions by all the gases and particles in the air. Blue light is scattered in all directions by the tiny molecules of air in Earth's atmosphere. Blue is scattered more than other colors because it travels as shorter, smaller waves. This is why we see a blue sky most of the time.


and if this is not sufficient to answer the perennial
parent-stumping question, The History Channel's
Universe provides the following,



yes today we parents have the answers; or at least
we know where to find them