Atmospheric
Optics
Earth Shadow & Belt of Venus, Antarctica ~
Three glorious images taken over three months . They show the progression of the Antarctic summer and melting ice each framed by the Belt of Venus. Yang Liu took these while at the Chinese Zhongshan Station on the Larsemann Hills of Princess Elizabeth Land, East Antarctica, 69°22′S, 76°22′E.
The top image was on February 16, '16. Below is the same scene 19 days earlier on January 28th. In January the near sea is still covered by ice floes. At far right a waning gibbous moon rests in the pink Venus glow.
All images ©Yang Liu, shown with permission
The dark purple-blue band hugging the horizon is the shadow of the solid earth cast through the atmosphere. and lots of words.
Above at the shadow's edge is the pink 'Belt of Venus'. Near the edge of the shadow the air is lit by highly reddened sunlight. Some scatters back towards the camera. Blue/violet light scattered by the atmosphere mixes with the red to give the rosy pink band. The sky colours at sunset and beyond into twilight are also influenced by the absorption of stratospheric ozone. See this page for a ray diagram.
Below: the scene on November 17, 2015. All is still frozen. At this latitude there is a period between late May and mid July when the sun never appears above the horizon. On 17th November it climbs to a high 40° and the sea ice succumbs to its heat.
