Shine on you Crazy Crescent!

Just a few days ago, this happened....




This is a very rare "conjunction". The photo shows the Moon, Venus and Jupiter, almost side-by-side.

This will not happen again until 2032.

What is interesting is that although the Moon is officially a "crescent", the whole disc is visible.

This is a phenomenon known as "earthshine", often seen on clear frosty days in the daylight in England.

What is happening is this: The Sun is shining on the Earth, and the moon is acting like a very crude mirror, reflecting light back to the earth FROM the earth.

It works like this.... Light from the Sun hits the Earth, bounces to the Moon, bounces off the Moon and back into our eyes.

The upshot is that we can see the unlit side of the moon. It is not lit by the sun, but by the blue-green planet 3/4 of a million miles away.

When I first saw this "earthshine" in the UK at the age of seven, I could not work out how I could "see" the "unseen" side of the Moon.

Yet another example of the wonder of physics.