Report of New Features Imaged in M 83, “The Southern Pinwheel Galaxy”

OTA: TAO 150 (f/7.3)

Camera: FLI - ML16200 (1.13 arcseconds/pixel)

Observatory: Deep Sky West, Chile

EXPOSURES:

Red: 10 x 600 sec.

Blue: 12 x 600

Green: 12 x 600

L: 12 x 600

H: 12 x 1800

Total exposure 13.5 hours

Image Width: ~1 deg

Processed by Alex Woronow (2020) using PixInsight, Skylum, Topaz, SWT

IMPORTANT: OPEN IMAGE B (CLICK ON IMAGE AT RIGHT) FOR THE ANNOTATED IMAGE SHOWING LOCATIONS OF THE NEWLY IDENTIFIED IN M 83



This image reveals five heretofore unreported and largely unrecognized features in and around the galaxy Messier 83. My detailed article provides more details as well as proposed origins for these features. Obtain it at https://www.dropbox.com/s/9vwwahjovsrv3we/M83%20Revealed.docx?dl=0 . Here I only list and quickly describe the five features:

(1) A hazy, Bright Halo, with smeared spiral-arm structure, surrounds, and is continuous with, the main galaxy. This halo is not entirely symmetrical, appearing wider at the right side of the galaxy (near the number ”2” in Fig B) and narrower on the left side.

(2) A Dark Halo encircles the Bright Halo and wraps the entire galaxy. (This halo can be difficult to see. Move back from this image, relax your vision, and the dark halo becomes more clearly apparent.) A true image of M 83, which better shows all the features, is here: https://tinyurl.com/M83jpg100)

(3) Beyond the Dark Halo, a faint bright arc appears from around 7 to 9 o’clock. It presents as if it were a portion of a spiral arm decoupled from the main galactic pinwheel.

(4) Still farther out, spanning from about 6 to 8 o’clock lies another smear of brightness, again mimicking a disarticulated spiral arm. It may join feature 3 at around 8 o’clock.

(5) This feature covers the rest of the image; the background has luminosity above that expected for empty space.

How did these features arise? Given that the literature does not even describe these 5 feature, no surprise that nothing in the literature conjectures on their origin. Again, My full exposition on this can be downloaded from https://www.dropbox.com/s/9vwwahjovsrv3we/M83%20Revealed.docx?dl=0.