NGC 5236 or M83 in Hydra, Southern Pinwheel Galaxy

The Southern Pinwheel Galaxy is a weakly barred, grand

design (two armed), spiral galaxy on the borders of

Hydra and Centaurus.  It contains 40 billion

stars and is 14.7 Mly from us.

Hover over the image for an annotated view.

Date:  24 May 2023, 30 and 31 May 2024, 11 May 2026

FOV:  approximately 30' × 20'; the angular size of M83 is about 12'

Rotation:  −0.009°

Telescopes:  Orion Apex 127mm Mak-Cass (1382mm,

nominally 1540mm, f/12.1) and

Celestron 9.25" EdgeHD 925 SCT (1632mm, f/7

with Celestron 0.7× reducer)

Guiding:  ZWO ASI120MM mini mono guide cameras,

SVBony SV165 Mini 40mm f/4 guide scopes

Computers:  ASIair pro and ASIair plus 256GB Raspberry Pi

Mounts:  ZWO AM5 (Mak-Cass) and AM7 (C-925)

Cameras:  ZWO ASI071MC pro, -10°C, OSC, gain 90 (2026) or

gain 240 (2023 and 2024)

ZWO ASI6200MC pro (APS/c), -10°C, OSC, gain 100 (2026)

Filters:  none (Mak-Cass) and Optolong UV/IR cut (C-925)

Stacking:  frames from Orion Mak-Cass except as noted

fourteen 240 second frames 24 May 2023,

eighteen 240 second frames 30 May 2024,

twenty-six 240 second frames 31 May 2024,

forty-two 300 second frames 11 May 2026, and

twenty-nine 300 second frames 11 May 2026 Celestron 9.25" EdgeHD

with 20 dark flats, darks, and flats preprocessed in Pixinsight

Total Time:  9 hours 47 minutes

Processing:  Pixinsight – DBE, SPCC, DynCrop, BlurXT, NoiseXT,

MultiScaleAdaptiveStretch → Stars, GHS, Sat

StarXT, MAS, MStr, GHS, HST, MAS,

PixelMath Add 0.25(MAS, MStr, GHS, HTS),

HDRMST66PhLm, Sat → Starless

PixelMath ScreenBlend(Stars, Starless), Scale

Location:  All sessions at Darling Hill Observatory near Vesper, NY

except 31 May 2024 at Crystal Lake near Redwood, NY