This year’s harvest moon, on Friday 16 September, will offer an extra special treat for stargazers in the form of a penumbral lunar eclipse, visible in certain parts of the world.
The term harvest moon refers to the full moon that falls nearest to the autumn equinox in the Northern Hemisphere, with the moon usually appearing to look full for some days before and after the actual event. It occurs most often in September. This year however, the harvest moon will also experience a penumbral eclipse that is due to peak at 2.54 pm Eastern Daylight Time (18:54 GMT) and should be visible to people in Africa, Asia, Europe, Australia and the western Pacific.
Unlike a total lunar eclipse, which sees the moon passing through the darkest part of Earth’s shadow, a penumbral lunar eclipse marks the passing of the moon through the very outer region of the Earth’s shadow. While it does not cause the same degree of reddish hue common with total lunar eclipses, it often causes darkening to appear on the surface of the moon. Those watching the moon this Friday may be able to notice varying degrees of shading around the edges, while viewing the surface with a telescope is advised for a better impression of the event.
Each month holds different names for the full moons that occur within that time period, according to Native American tradition. The name harvest moon arose in the Northern Hemisphere because it occurs in the autumn. It is followed by the hunter’s moon, the beaver moon and the cold moon.