Radio Galaxy Zoo Talk

ARG0002585, people (radio) are strange

  • firejuggler by firejuggler

    the field is pretty empty of radio wave, but there is a line of medium intensity radio wave right by the middle.
    Is it possible that we are seeing a disk on edge and there is only this part that has an active radio field?

    Posted

  • akapinska by akapinska scientist

    @firejuggler: I wouldn't pay too much attention to that "line of medium intensity" you refer to - these are image processing artifacts. What you are seeing in this radio image is the brightest signal of a radio lobe - unfortunately the FIRST survey is not sensitive to low surface brightness radio signal that most likely we are dealing here with so you will not see the whole radio lobe (which you will with the NVSS survey!). The radio galaxy is really large so you neither can see the radio galaxy core (which we try to match to infrared signal) - it's just because the image size is too small to encompass this radio galaxy in full. The full image of this radio galaxy is this (NVSS):

    enter image description here
    enter image description here

    As @antikodon guesses that is most likely a #giant. It's roughly 8 arcmin in size and so it's going to cross the magic 1 Mpc giant selection criterion already at redshift ~0.12 - what I mean is if its host galaxy is already as close as z~0.12 this radio galaxy will be a giant!

    With regards to your question - radio waves are completely different to this what we are used to see in optical images of galaxies. The radio emission will be coming from supernovae or radio jets, so you'd normally see either a blob, often compact radio source coincident with the host galaxy (in the RGZ images: IR) or two jets or lobes on either side of and often extending well beyond the host galaxy. So in radio emission you don't really look for disks, bars, bulges etc because you can't see it and these structures don't produce radio emission. If looking at less/not active galaxies with radio emission, then the radio emission will be coming from supernovae, and so regions with star formation - that's not the case here though; here we have part of a large radio lobe created by very powerful jet 😃

    Posted

  • Dolorous_Edd by Dolorous_Edd

    Hmm .. I got ~6.3' from FIRST

    As host I will propose SDSS J075441.67+232423.0

    with z = 0.130 it will be ~850kpc

    BUT there is a weak VLA FIRST signal near ALLWISE J075443.29+232342.5 so is it a host or unrelated source?

    or I don't understand something?

    Posted