Radio Galaxy Zoo Talk

ARG00013mg: nice ringed red spiral near the host

  • JeanTate by JeanTate

    SDSS J085105.75+410311.2:

    enter image description here

    Good example of why you can't blindly trust SDSS PhotoObj fracDev parameter values to test if a galaxy is an elliptical: all five bands are 1 (= compatible with a deVaucouleurs radio flux profile, one which most ellipticals ~have)!


  • ivywong by ivywong scientist, admin

    Definitely an outer ring but early-types can have outer rings too. I cannot tell any spiral/disk structure from the SDSS image alone....


  • JeanTate by JeanTate in response to ivywong's comment.

    Thanks Ivy.

    early-types can have outer rings too

    I know that even S0 ('lenticular') galaxies can have outer rings, but they are disk galaxies (well, they have disks); I had not heard that pure ellipticals have been found to have outer rings (unless you count the very rare ring galaxies - which are rare types of "bull's eye" collisions).

    I cannot tell any spiral/disk structure from the SDSS image alone

    If you look closely, you can see that this is more a two-arm spiral than a ringed spiral: the most prominent arm begins near N, and gets increasingly far from the bulge until it peters out at ~S; the other obvious arm - which is very fat - begins at ~7 o'clock and winds out, ending at ~10 o'clock. At least, that's how it seems to me.

    I'm not sure if zooming in helps, but anyway:

    enter image description here