Explanation:
Also known as the Moon's ashen glow,
Earthshine is
Earthlight illuminating the Moon's night side.
Taken on
Nowruz,
the March 20 equinox, from Esfahan, Iran, planet Earth,
this telescopic image captures strong Earthshine from
an old Moon.
The darker earthlit disk is in the arms of a bright sunlit crescent.
But the
view
from the Moon would have been enchanting too.
When the Moon appears in Earth's sky as a slender crescent,
a dazzlingly bright, nearly full Earth would be seen
from the lunar surface.
The Earth's brightness due to reflected sunlight
is known to be strongly influenced by cloud cover.
Still, a description of Earthshine, in
terms of sunlight reflected by Earth's oceans in turn illuminating
the Moon's dark surface, was written 500 years ago by
Leonardo
da Vinci.
