M83, Southern Pinwheel Galaxy

    Caption: M83 (AKA the Southern Pinwheel Galaxy, NGC 5236).

    Features:
    1. Constellation: Hydra
    2. Hubble type: SABc: i.e., intermediate spiral galaxy of subtype c. Being an intermediate spiral means it has only a small bar---but you can get a drink.
    3. Spiral galaxy: Yours truly thinks M83 looks like a flocculent multi-arm spiral galaxy, but it is classified as a grand design spiral galaxy (see Wikipedia: M83: Characteristics). However, the thinking circa 2021 is that there is NO ABSOLUTE distinction between flocculent spiral galaxies and grand design spiral galaxies (see Wikipedia: SSPSF model).
    4. Galactic inclination: face-on or nearly so.
    5. Redshift 513 ± 2 km/s. Because of its closeness to Milky Way, the redshift is probably has significant components of both Doppler effect shift and cosmological redshift z.
    6. Distance: 4.5 Mpc ≅ 14.7 Mly.
    7. Galactic disk diameter: ∼ 15 kpc or about half of the Milky Way's diameter (see Constellation Guide: Southern Pinwheel Galaxy----Messier 83).

    Credit/Permission: © ESO, 2005 (uploaded to Wikipedia by Lars Lindberg Christensen (AKA User:Lars Lindberg Christensen), 2008) / Creative Commons CC BY-SA 3.0.
    Image link: Wikipedia: File:M83 - Southern Pinwheel.jpg.
    Local file: local link: galaxy_spiral_m83.html.
    File: Galaxies file: galaxy_spiral_m83.html.