A. On the way to school recently my little boy called out excitedly, “Look Dad, there’s
the Moon! But why can we still see it in the day?”
The simple answer is for the same reason we can see other things during the day,
be that a table, some curtains or a cat – because light shines on it and we can see
the light that reflects off it (or, in other words, reflected light enters our eyes
and our brain interprets this and creates a picture). The Moon is just another object
being lit by sunlight; it is in constant orbit around the Earth which means that
– when it is in the ‘right’ place - we can see it along its path. So why don’t we
see it all the time then?
Well if, for example, the Moon is positioned in its orbit between the Earth and the
Sun, the side facing us wouldn’t be lit up and so we wouldn’t be able to see it.
In addition, on a really bright sunny day, when the sky is extremely blue, the sunlight
reflecting off the Moon can get ‘washed out’.
After explaining this to my son, he slowly nodded his head and inquired, “so why
can’t we ever see the stars during the day?” The reason is for that is stars are
much further away from us than the Moon and the light shining from them is somewhat
fainter. So, during the day when the sky is brighter, the starlight simply gets lost
in the skylight above us. However, if you had a powerful telescope and pointed it
towards some of the larger stars, you should still be able to see them even during