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Old 27-05-2014, 08:42 PM
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mental4astro (Alexander)
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mental4astro is offline
 
Join Date: Jun 2008
Location: sydney, australia
Posts: 4,979
M83 - the Southern Pinwheel

Hi all,

This is one baby I've been wanting to sketch for a LONG time.

M83 has eluded my sketch pad for years. Poor weather and conditions being the main contributing factors. Conditions in particular on those times it was a viable target were particularly frustrating. M83 requires nothing less than very good conditions to bring out the detail. Its low surface brightness falling victim to poor transparency.

This year's South Pacific Star Party finally presented the best opportunity,

What a beauty. First look at M83 this night had me say "Wow! That's spectacular!". A blatant bar. A brilliant core. Two definite arms that fade out into an asymmetrical round shape. M83's outer areas have a mottled appearance. A 'tag' is visible that comes off the end of one of the arms - that, and the asymmetrical shape suggest to me either recent or current external gravitational influence. Photographic evidence to this is the enormous amount of HII regions. Such activity is the result of significant gravitational tidal influence. This is all my own speculation from observable evidence.

This galaxy was a joy to sketch. Big, meaty, expansive. The only regret I could have is my eyes were very fatigued at the time, so the HII regions eluded my observation when I 'blinked' M83 with an OIII filter.

Object: M83 galaxy
Scope: 17.5" push-pull dob
Gear: 13mm LVW, 154X
Location: Wiruna, Ilford, NSW, Australia
Date: 24th May, 2014
Media: White soft pastel and white ink on A4 size black paper
Duration: approx. 45min
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