Explanation:
A celestial prelude to
today's solstice,
the June 15
total lunar eclipse
was one of the longest in recent years.
It was also one of the darkest, but not completely dark.
Even during totality, a somber, red lunar disk could be seen in
the starry night sky, reflecting
reddened light falling on to its surface.
Seen from a
lunar perspective,
the ruddy illumination is from all the sunsets and sunrises
around the edges of a
silhouetted Earth.
In this sharp portrait of the eclipsed Moon from Granada, Spain,
the Moon's edge reflects a
bluish tinge
as well as it emerges from Earth's
umbral shadow.
The bluer light is still filtered through Earth's atmosphere, but
originates in rays of sunlight passing through layers high in
the upper stratosphere.
That light is colored
by ozone that absorbs red light and transmits bluer hues.