Moon trails over Skiathos


 

IMAGE DETAILS

Date + Time ...............................   25/ 4 / 2013 - 16:15 UTC
Location ....................................   Nunki Observatory
Optics .........................................
  Canon EFS 18-200 mm (working at 18mm - f/3.5)
Camera .....................................   Canon Eos 50D
Exposure Time.........................   ISO 400-800 - 25X30 sec
Mount .......................................   portable tripod
Processing Details .................    Photoshop CS 5
Details
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Summary Authors: Nikos Paschalis; Jim Foster (EPOD)
The image above is a time lapse of the full Moon rising over Skiathos Island (in the background), Greece. It's composed of approximately 20 frames taken 30 seconds apart on the evening of April 25, 2013. Note that the Moon subtends the same angle of the sky (1/2 degree) during its rise -- it's not any bigger when it breaks the horizon than it is when well up in the sky. However, the color of the Moon does change as moonrise progresses from red to orange to yellow to white. These color changes are attributed to changes in the path length of moonlight that reaches our eyes. Red colors (long wavelengths of visible light) result from the longer path lengths when the Moon is very low in the sky. As the Moon rises higher and higher, our atmosphere scatters the longer wavelengths about as much as the shorter wavelengths, so the Moon appears white.
 

Nikos Paschalis