Archive for September 25, 2018

09/25/2018 – Ephemeris – The harvest moon effect

September 25, 2018 Comments off

Ephemeris for Tuesday, September 25th. The Sun will rise at 7:33. It’ll be up for 12 hours and 1 minute, setting at 7:34. The Moon, 1 day past full, will rise at 8:17 this evening.

The full, or nearly full moon, just rising, looks like a large orange pumpkin. The color, like the red of the sunset is caused by the scattering out of blue light by the atmosphere. It can happen at any full moon, not just the Harvest Moon, which was officially yesterday. What the Moon around the Harvest Moon does do is rise only a little later each evening. This helped the farmers in earlier times extend daylight to bring in the crops. On average the moon rises or sets 50 minutes later each night. However when the Moon is in the part of the sky where it is moving northward as well as eastward, then it rises only a little later each night. Tomorrow’s Moon will rise only 27 minutes later than it will this evening.

The times given are for the Traverse City/Interlochen area of Michigan. They may be different for your location.


Harvest moon effect 2018
The harvest moon effect 2018 showing the shallow path of the Moon near moonrise and the intervals between them for 5 consecutive dates. Created using Cartes du Ciel (Sky Charts).