All-Sky with Gegenschein, Zodiacal Band and Milky Way on the horizon

Mousover for labels. Click on the image for a higher resolution version.

Ok, you know what that bright band is. But imagine you look at this image without any introduction. That band, at a first look, can be mistaken for the Milky Way. No! That is the Zodiacal Band and the Gegenschein, a very faint brightness due to the dust lying on the Ecliptic plane. The Gegenschein is exactly on the opposite side of the Sun, and the little higher brightness is due mainly to two reasons: the backscattering of fully illuminated dust particles, and the little higher density of dust near the lagrangian point.
The Milky Way seems to be completely disappeared. In fact the Southern Galactic Pole is at zenith. But at a closer look, the Milky Way Bulge is noticeable toward West, while setting. This view is possible thanks to the latitude of Tivoli farm (-23°). At the same latitude the Milky Way Bulge reaches zenith 6 hours before, look at this image.

Technical data
Optics Peleng 8 mm f/3.5
Focal Length 8 mm
Focal Ratio f/5.6
Exposure Time 40 min (single exposures of 10 min)
CCD Canon EOS 5D with Baader filter
Sensitivity 800 ISO
Location Tivoli Farm (Namibia) at 1350 m height
28 August 2011
Mount Losmandy G11
Tracking none
Temperature and humidity T= +5°C, RH=47%
Sky brightness at zenith (with SQM-L) from 21.9 mag/arcsec^2 (not one of the darkest nighs we got)
Notes This image is a collaborative effort of the Namibia 2011 expedition. Processing: Lorenzo Comolli. Images by: Lorenzo Comolli, Luigi Fontana, Giosuè Ghioldi, Emmanuele Sordini.

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