Galaxy Zoo Talk

Shades of blue

  • Ghost_Sheep_SWR by Ghost_Sheep_SWR

    What is the cause of the blue areas top + bottom? It's referenced often as AGN galaxy.

    Or might the bright foreground star at top be causing it?

    enter image description here

    http://legacysurvey.org/viewer/jpeg-cutout-decals-dr2/?ra=322.7204&dec=4.0417&size=512&pixscale=0.08&bands=grz

    enter image description hereSDSS DR9

    Posted

  • Budgieye by Budgieye moderator

    I looked around at nearby objects in DECaLS dr2 looking for similar bright objects that might have the same blue flare, and I can't find one, though the stars in the image have a tiny trace of blue. It might not be a optical artifact.

    So maybe the blue colour is related to the quasar?

    Let me think. AGN are magenta- coloured from 0.03 to 0.1 in SDSS. It is a Seyfert1 quasar galaxy, so we are looking nearly straight into the nucleus.

    enter image description here

    http://legacysurvey.org/viewer/jpeg-cutout-decals-dr2/?ra=322.7204&dec=4.0417&size=512&pixscale=0.08&bands=grz

    enter image description here dr2

    http://legacysurvey.org/viewer

    ra, dec

    322.7203 ,4.0417

    21:30:52.88,+04:02:30.27

    2MASX J21305288+0402300

    13 references on NED, and one is from Hubble Space Telescope!

    http://ned.ipac.caltech.edu/cgi-bin/ex_refcode?refcode=2000MNRAS.315..498S

    They didn't publish this AGN

    raw data

    https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html?searchQuery=21:30:52.88,+04:02:30.27

    seems to be there.

    enter image description here

    Hmm.. what do I do now?

    Posted

  • c_cld by c_cld

    AGZ000bhc0 Similar objects are Seyfert 1 (Sy1)

    As typical example Mrk 1513 was posted http://www.galaxyzooforum.org/index.php?topic=273134.msg222939#msg222939

    587730772799127810 and 1237656494024032525

    viewed in DECaLS DR1

    and DR2

    Mrk 1513 Mrk 1513

    Posted

  • Ghost_Sheep_SWR by Ghost_Sheep_SWR

    Hey that's cool, missed the Hubble reference. Too bad it's only RAW data, i'll search some more later.

    So when comparing SDSS and DECaLS, it seems the blue parts are only visible in DECaLS, so there you can visibly spot them?

    Wondering if the blue is caused by the jet nearly pointed in the camera, or an actual feature in the galaxy? Probably the first.

    Posted

  • Ghost_Sheep_SWR by Ghost_Sheep_SWR

    Found some images on the HLA, no colored ones unfortunately. And slightly oversaturated it seems. Can't handle the FITS files so stuck to fiddling with the interactive display 😃

    http://hla.stsci.edu/hlaview.html#Images|filterText%3D%24filterTypes%3D|query_string=21%3A30%3A52.88 %2B04%3A02%3A30.27 r%3D0.5d&posfilename=&poslocalname=&posfilecount=&listdelimiter=whitespace&listformat=degrees&RA=322.720333&Dec=4.041742&Radius=0.500000&inst-control=all&inst=ACS&inst=ACSGrism&inst=WFC3&inst=WFPC2&inst=NICMOS&inst=NICGRISM&inst=COS&inst=WFPC2-PC&inst=STIS&inst=FOS&inst=GHRS&imagetype=best&prop_id=&spectral_elt=&proprietary=both&preview=1&output_size=256&cutout_size=12.8|ra=&dec=&sr=&level=&image=&inst=ACS%2CACSGrism%2CWFC3%2CWFPC2%2CNICMOS%2CNICGRISM%2CCOS%2CWFPC2-PC%2CSTIS%2CFOS%2CGHRS&ds=

    Only real discerning difference with DECaLS so far is a visible foreground(?) star near the center and a dark object even closer at 1 o'clock, or also a star that's overshined by the galaxy center. And maybe jet-like feature to 1 o'clock or artifact, can't tell the difference here.

    enter image description here

    enter image description here

    enter image description here

    EDIT Files are combined so COULD be used for different colouring.

    Posted