towards Autumn (and the end of Sum...)

… and gathering Swallows twitter in the skies 
(John Keats )

Today the Earth reaches that point in its journey round the Sun where day and night are roughly equal in length.  If you look in your diary (you do still have a diary don’t you?) you’ll see that September 22nd is the date, this year, of the Autumnal Equinox.  This is a big deal in the world of science and in particular, astronomy.  

It’s also a big deal for the rest of us because it means the end of Summer.