An occasional habit of ours is enjoyment of company while viewing the effects of sunset from our east facing patio. The Sunday of January 20, 2019 I prepared for total lunar eclipse by researching moon rise. Online charts (search for “moonrise”) give the time and compass heading for particular locations.
This departing cruise ship was in line of sight and I was disappointed to have missed effect of the reflected sunlight on the myriad windows we so often enjoy with friends. The preceding and following photographs present an illusion of a cruise ship appearing larger than the full moon, the effect of the much larger body viewed from an enormous distance.
In these photographs a newly risen full moon appears to emerge from ocean cloud cover. A full moon is a requirement of a lunar eclipse, it is not possible to have an eclipse without a full moon, although the reverse is not true.
The apparent large size of the moon low in the sky is an optical illusion caused by the alignment of vision with earth-bound objects on the horizon.
A simple experiment is to find a pebble that is the same size as the newly risen full moon when held at arm’s length. Wait until the orb is well up and apparently smaller. You will find the same pebble covers the moon. On the horizon or high above, the full moon covers the same angular diameter.
Copyright 2019 All Right Reserved Michael Stephen Wills