M83 in Hydra


Copyright 2006 Hap Griffin

M83, also known as the Southern Pinwheel Galaxy, is a "barred spiral".  That is, it is in a class of galaxies that have a bar across the central region with well defined and dynamic spiral arms.  The knots of reddish nebulosity among the spiral arms are regions of active star birth whereas the bluer regions are areas of hot young stars entering their normal sequence of life.  The bar structure contains more yellowish stars which indicates a much older population.  The brown dust lanes parallel to the central bar indicate the remains of stars from this older population which have blown themselves apart, throwing the material they synthesized during their lives back into the galaxy for formation of future generations of stars.

Note the two more distant spiral galaxies just to the left (east) of M83.  The larger one is ESO444-85 at magnitude 16.  

M83 lies at a distance of 15 million light-years.

Date/Location:    March 25, 2006     Griffin/Hunter Observatory    Bethune, SC
Instrument:    Canon 350XT Digital SLR (modified) through 10" Meade RCX400 
Focal Ratio:   f8
Guiding:    Auto through Orion ED-80 w/ SBIG ST-237
Conditions:    Visually clear
Weather:    32 deg. F 
Exposure: 105 minutes total @ ISO 800 (21 x 5 min exposures)
Filters:    Baader UV/IR Block
Processing:    Focused and captured with DSLRFocus.  Pre-Bayer Interpolation calibrations, frame alignment and stacking, Adaptive Richardson_Lucy deconvolution, scaling and JPEG conversion with ImagesPlus.  Color correction, curves and levels with Photoshop 6.  Noise reduction with NeatImage.