Radio Galaxy Zoo Talk

SDSS J114722.13+350107.5

  • Dolorous_Edd by Dolorous_Edd

    First of all, this one is known

    The source , I think , is SDSS J114722.13+350107.5 NED link

    Looks like a classical triple, though right lobe, from the looks of it , decided to be a rebel

    NVSS 0.3 degree

    enter image description here

    NED link CGCG 186-048


  • akapinska by akapinska scientist

    Yes, it is very well known. It's fairly peculiar because of its structure and the fact that it's restarted (the core is classified as GPS source). For more scientific reading check out this:


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

    I just learned something new: "GPS" here means "Gigahertz Peaked Spectrum" (and has nothing to do with the satellites which help me drive to a place I've never been before, via a gadget which I attach to the dashboard of my car 😉 )

    What do GPS sources have to do with RGZ? Specifically, are all lobes known to be NOT GPS sources (so radio/optical/IR matching can be done more effectively)?


  • akapinska by akapinska scientist

    Ah yes! 😄

    GPS sources are young radio galaxies, we usually see them as compact radio sources; to see them as small lobed radio galaxies one needs to use very high resolution observations (VLBI). These sources are usually very young (say 10,000 - 100,000 yrs old) and of size not more than 1 kpc. Their name comes from the shape of their radio spectrum, unusually it peaks at gigahertz frequencies as opposed to typical MHz (but it depends on redshift if one looks at observed flux densities, so the rest frame one peaks at GHz). There should be blog post of mine at some point on how different stages of growing radio galaxy look like.

    Now this source is very special because it has its huge giant radio structure from previous activity (the weirdly shaped large scale lobes), and the new one that is the central GPS source - sign of the restarted activity.

    But yes, GPS sources are usually easy to match to the hosts because, due to their size, they must coincide with the optical/IR sources - they are still embedded in their host galaxy, if that's what you asked about.