Penumbral lunar eclipse

Friday 18th Oct 201322:39

The Moon will skim through the edge of the Earth’s shadow, termed the penumbra. At no point will the Sun be more than partially eclipsed by the Earth, as seen from the surface of the Moon, meaning that whilst Earth-based observers will see a reduction in the Moon’s brightness, no part of its disk will be completely within the Earth’s shadow (umbra) and no part of its disk will appear completely dark. Maximum eclipse will occur at 23h51 UTC, at which time 76.5% of the Moon’s disk will be in the Earth’s penumbral shadow. The eclipse will last for 239 minutes, from 21h51 to 01h50 UTC.

Penumbral events are very subtle events to observe.The apparent dimming of the Moon’s disk is typically only perceptable to a trained eye, especially when, as in this case, a relatively small fraction of the Moon’s disk enters the penumbral, and no part of its surface sees an especially deep eclipse of the Sun’s light reaching it.

On this occasion the Moon will lie at a declination of +10°54′ in the constellation Pisces, and so will be seen to best advantage in the northern hemisphere; it will be possible to see it at latitudes between 80°N and 59°S. The eclipse will be visible over more than half of the Earth’s surface, but will be best viewed from longitudes around 2°E, where maximum eclipse will occur at midnight, local time.

This eclipse is a member of Saros series 117.