Physics Photo of the Week
Earthshine on the Rising Moon
When we see
the Moon as a crescent we often see the whole Earth-facing side dimly
lit as wel as the bright crescent. This light on the dark part of
the Moon is called
"earthshine". Reflected light from the planet Earth radiates out
into space and lights up the night side of the Moon. It is the
same effect as Moonshine on Earth (the light of the moon, not an
This photo was taken over a year ago (January 23, 2009) when we had a
clear pre-dawn view of the waning crescent Moon. The Moon is rising as can
be seen by the animated sequence at right. The pictures in the
animation were taken once every 10 seconds and played back at 10 frames
per sec - speeding up the motion by a factor of 100. Notice that
the sky is gradually becoming brighter as dawn or sunrise is
approaching. The Sun will rise in the lower left part of the
picture in the approximate position of the line of the rising
Moon. On close examination of the animated picture, thin clouds
can be seen passing in front of the Moon.
Photo of the
published weekly during the academic year on Fridays by the Warren
Wilson College Physics
Department. These photos feature interesting phenomena in
the world around us. Students, faculty, and others are invited to
submit digital (or film) photographs for publication and
explanation. Atmospheric phenomena are especially welcome.
Please send any photos to firstname.lastname@example.org.
All photos and discussions are copyright by Donald
Collins or by the person credited for the photo and/or
discussion. These photos and discussions may be used for private
individual use or educational use. Any commercial use without
written permission of the photoprovider is forbidden.
see the Physics Photo
the Week Archive.
Observers are invited to submit
digital photos to: