Explanation:
During September 7th's lunar eclipse,
the Moon slid
through the Earth's shadow.
Extending
into space, Earth's cone-shaped shadow has two distinct
parts, the lighter, outer part or penumbra, and the darker,
inner shadow called the umbra.
For this eclipse, the lunar disk
just grazed the
shadow's dark inner umbra.
As a result, only a small part of the Moon was noticeably
eclipsed, but
the
performance still attracted the attention of
Moon watchers along the Earth's night side.
In this
creative scene, eclipse enthusiasts have
matched the curve of a hoop to
the eclipsed portion of the Moon - demonstrating the apparent
size and position of the lunar disk relative to the umbra
and penumbra.
Of course, it's only
shadow play.
