Radio Galaxy Zoo Talk

QSO or radio galaxy behind a star? No redshift (spec,phot)!

  • zutopian by zutopian

    QSO or Star?

    enter image description here
    http://skyserver.sdss.org/dr12/en/tools/explore/Summary.aspx?id=1237662199893327884

    Radio galaxy behind a star or host galaxy of a QSO?

    enter image description here
    http://skyserver.sdss.org/dr12/en/tools/explore/Summary.aspx?id=1237662199893327895

    Curiously, this object is neither listed as QSO in NED nor Simbad! There is no redshift (neither spec nor photometric) available in SDSS/NED! Could someone please estimate the photometric redshift of this object?
    Or is it a star? There is a part of a galaxy visible behind the blue object (in the center of the 2nd image)! Is it a radio galaxy, which is overlaped by a star? Or is it a part of the host galaxy, which harbours a QSO?
    The galaxy has also no redshift (spec, phot)! What might its morphology be? I guess spiral or disc galaxy because of its colours!

    Posted

  • Dolorous_Edd by Dolorous_Edd

    What might its morphology be?

    IMO ETG and judging by color z less than 0.4

    Star is also dubious just by eyeballing if it is a STAR it should be hot O type

    Posted

  • 42jkb by 42jkb scientist, admin

    The host is most likely not a star as stars with radio emission are hard to detect.

    Posted

  • c_cld by c_cld

    The bright blue object seems binary:

    1237662199893327884 1237662199893327884

    Is it a coincidence overlap of foreground star and galaxy or two galaxies? visual or spectroscopic binary?
    I cam't say even when looking at each band by Aladin.

    Not much to tell by querying Vizier...

    Posted

  • ivywong by ivywong scientist, admin

    The SDSS images have the following flags:
    DEBLENDED_AT_EDGE STATIONARY BINNED1 SUBTRACTED INTERP COSMIC_RAY CHILD

    and so, we have to be very careful with how we interpret the flux/colors that result for this particular source as per:
    https://www.sdss3.org/dr8/algorithms/flags_detail.php

    Posted