Airglow Over Germany
August 10, 2012
Photographer: Jens Hackmann; Jens' Web site
Summary Author: Jens Hackmann; Jim Foster
While waiting for the occultation of Jupiter by the Moon last month, I captured the phenomenon known as airglow in the nighttime sky above Baden-Wurttemberg, Germany. Even when clouds passed over (they appear golden on this long exposure photograph), the intensity of the Milky Way was fabulous. At first, I didn't recognize that the faint greenish strips actually resulted from airglow, but when I was able to examine my image more closely, I knew this is what I had observed. I also could see the striping with the unaided eye, but the green color could only be detected with the long exposures. This striping is evidently caused by atmospheric gravity waves propagating upward into Earth’s mesopause (55-50 mi or 90–100 km above the surface) in such a way to disturb the airglow layer. Note that the magenta line at right center is the path of an airplane.
Photo details: Camera Maker: Canon; Camera Model: Canon EOS 5D Mark III; Lens: EF15mm f/2.8 Fisheye; Focal Length: 15mm; Aperture: f/2.8; Exposure Time: 45.000 s; ISO equiv: 1600; Exposure Bias: none; Metering Mode: Matrix; White Balance: Auto; Flash Fired: No (enforced); Software: Adobe Photoshop Camera Raw 6.7 (Windows).