Milky Way mosaic - from Scorpio to Orion (2011 edition)

Advice: click the FULL SCREEN icon (at right). Zoom with CTRL and SHIFT buttons or mouse wheel.
In the above window you can zoom and pan in the high resolution image. Here is a version without labels.

The Milky Way is our galaxy, maybe the only one we do not accurately know the shape! That's because we are inside and many parts are obscured from our view due to strong absorption of the dust. Thanks also to radio telescope we actually know this is a spiral and should not be too different from other spiral ones, such as the Andromeda Galaxy M31.
This image shows the dust with a yellowish tint, while the many red nebulas are hydrogen clouds that emit the typical H-alpha light at 656.3 nm, a deep red. Many other objects can be identified, such as open and globular clusters, and planetary nebulas. Only a few galaxies are found, due to the same reason we cannot look at the Milky Way center: the dust absorption.
As can be found from the technical data below, this image is the result of a huge work, both of acquisitions (many nights from different observing sites and seasons) and of processing (done in two stages, made of many days of work, to get an homogeneous result from inhomogeneous data, mainly due to light pollution gradients).
This image contains the regions between Scorpio and Orion, so from summer constellations up to winter constellations. Two year ago I've processed the first 5 panels, (from Scorpio to Cygnus) and I've put that work-in-progress online, now the work I could do from Italy is finished, I'll need to go to the Southern hemisphere to complete! ;-)


Technical Data
Optics Canon 50mm f/1.8 mkII
Focal Lenght 50 mm
Focal Ratio f/4
Exposure Time Total: 9h20m (single exp of 10 min); 10 panels of about 1 h each
CCD Canon EOS 5D with baader filter
Sensitivity 400 ISO
Location A: Colle dell'Agnello (CN, Italian Alps) at 2700 m height - Panels 1, 2, 3, 4, 5 (Scorpio to Cygnus)
B: Selva (PC, Italian Appennines) at 1400 m height - Panel 6 (Cepheus)
C: Passo del Tomarlo (PC, Italian Appennines) at 1400 m height - Panels 6, 7 (Cepheus and Cassiopeia)
D: Monte Bisbino (CO, Italian Alps) at 1300 m height - Panels 8, 9 (Perseus and Auriga)
E: Capanne di Cosola (AL, Italian Appennines) at 1500 m height - Panel 10 (Orion)
Date
A: 16-17 August 2009 (two nights)
B:
19 September 2009
C: 16 October 2009
D: 12 February 2010
E: 13 March 2010
Mount Kenko NES and Gemini G-41
Tracking only motor, no corrections
Temperature and humidity A: T= +8°C, RH=60%
B:
T= +9°C, RH=100%
C: T= +0°C, RH=80%
D: T= -5°C, RH=50%
E: T= -3°C, RH=50%
Sky brightness at zenith (with SQM-L) A: 21.5-21.6 mag/arcsec^2
B: 21.2-21.3 mag/arcsec^2
C: 21.3-21.4 mag/arcsec^2
D: 20.4-20.6 mag/arcsec^2 (quite light polluted)
E: 21.4-21.5 mag/arcsec^2
Notes A hard project that took me a lot of nights of imaging and really may days of processing!

HTML Editing and Publishing by Lorenzo Comolli. Email me at comolli@libero.it.
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