What is the ‘harvest moon’? Most people think of a very bright full moon at any time in the late summer or early autumn, around harvest time, but defined properly, it is the full moon closest to the autumnal equinox of September 22nd to 23rd in the Northern Hemisphere.
Usually seen in late September, but very occasionally in early October, the harvest moon was so called because, rising just after sunset, it gave enough light for the harvest to continue on into the night. Before the use of modern machines and even today with all our technology a speedy harvests are important to prevent bad weather spoiling the crop.
Earlier civilisations held great store by the phases and cycles of the moon and timed the planting and harvesting of crops to coincide with its waxing and waning.
<ul><li>Despite the obvious and daily influence of the moon on the waters of the oceans it is unlikely that it has </li></ul><ul><li>any marked effect on </li></ul><ul><li>weather patterns around </li></ul><ul><li>the earth and I tend to believe the old adage, </li></ul><ul><ul><ul><li>‘ The moon and the weather may change together. </li></ul></ul></ul><ul><ul><ul><li>But a change in the moon will not change the weather.’ </li></ul></ul></ul>
There is, however, no doubt that the so-called harvest moon can look extremely large and can exhibit yellow, orange or even pink hues. Several theories have been put forward to explain the large size of the moon when it sits near the horizon compared to it usual size when high in the sky. This moon illusion appears to be due to the fact that we see it in relation to other objects when it is low down and our brain makes us see it larger. Hard to believe I know, but I am reliably informed that it does not appear larger when photographed near the horizon. And the camera never lies!
The low moon can also appear with a pale yellow, orange or red tinge. This is due to the refraction of light through more atmosphere when the moon is low in the sky. Atmospheric particles and even volcanic dust or pollution scatter the light producing a similar effect to that seen in some sunsets. Ted Hughes caught the idea well with:- ‘ The flame red moon, the harvest moon rolling along the hills, gently bouncing, a vast balloon.’
Then there’s that very odd time when two full moons fall in a single month. This event is so infrequent that it gives its name to any event that occurs very, very occasionally, ‘ once in a blue moon, ’ in fact.