2019 September 26
Explanation:
An old Moon rose this morning, its waning sunlit crescent
shining just above the eastern horizon before sunrise.
But
earthshine, light reflected from a bright planet Earth,
lit the shadowed portion of the lunar disk and
revealed most of a familiar lunar near side
to early morning risers.
In fact, a description of earthshine in terms of sunlight reflected
by Earth's oceans illuminating the Moon's dark surface
was written over 500 years ago by
Leonardo da Vinci.
One lunation
ago this old Moon also rose above the eastern horizon.
Its sunlit crescent and
da Vinci glow were captured in
stacked exposures from the Badain Jilin Desert of
Inner Mongolia, China on August 29,
2019.
This year marks the 500th anniversary of Leondardo da Vinci's death.