Galaxy Zoo Talk

Another green pea?

  • planetaryscience by planetaryscience

    Not sure what the current state of these objects are... but here's a little object that looks exactly like a green pea. What do you guys think?

    http://skyserver.sdss.org/dr13/en/tools/explore/Summary.aspx?id=1237656909037699396
    356.072802247 +1.149934452

    enter image description here

    Posted

  • Budgieye by Budgieye moderator

    Green pea? correct colour. No spectrum,though. We should tag a scientist.

    Photoz is about right, peas are green at 0.1 to 0.35

    z 0.357

    zErr 0.085

    doesn't seem to be a filter artifact.

    could possbly be a quasar z=4.

    Literature search

    No mention in NED, Talk or Forum.

    http://cas.sdss.org/dr7/en/tools/explore/obj.asp?id=587731187812794905

    587731187812794905 1237656909037699396

    SDSS J234417.47+010859.7

    extra info

    Galaxy Redshift Chart https://talk.galaxyzoo.org/#/boards/BGZ0000007/discussions/DGZ0000ulp?page=2

    3.8 Green peas, compact starburst, Blue compact starburst , OIII objects https://talk.galaxyzoo.org/#/boards/BGZ0000001/discussions/DGZ0000wrb?page=3&comment_id=53d8b93a0d43f77bb6000f98

    Posted

  • klmasters by klmasters scientist, admin

    Scientist's assemble! 😉

    Posted

  • klmasters by klmasters scientist, admin

    Honestly though I'm not much of a green pea expert. I'll point out the thread to Carie Cardamone for her expert opinion. 😃

    Posted

  • Budgieye by Budgieye moderator

    Well I think I had contacted her, but I'm not sure if I had an up to date email address.

    Little round green things are hard to identify. There is about 8 things they could be.

    Posted

  • ccardamone by ccardamone scientist

    It definitely looks like a green pea looks. I've been battling around in my brain what to do with objects with no spectra. It would be great to be able to increase the # of peas, but without spectra there is some uncertainty in what's causing the green color (perhaps another emission line at a very different redshift. That would mean it could be a distant AGN, also interesting but not Star Forming pea-like. I'll see if I can use this one as a case study as I look into it more.
    However, for clustering studies (my current focus) distance information can be very useful.

    Thanks!
    Carie

    Posted

  • planetaryscience by planetaryscience

    I can rule out a quasar with 80% certainty given that the object is completely invisible in WISE images, which would normally require this object to be a spectrally odd quasar if anything.

    Furthermore, PANSTARRS, SDSS, and DECaLS all independently confirm some minor elongation in the 1 o'clock/7 o'clock direction, rather than a point-like source. Based on the photoZ, it would be something between 13,000 and 28,000 light years across- a bit large for a pea, but considering the photoZ error...

    Posted

  • Budgieye by Budgieye moderator

    Brilliant find, planetaryscience. Dr Cardamone, I thought that SDSS had been computer searched for "green" objects. How did this one get missed?

    I will put a note to this in The Index, so that I don't lose it.

    Posted

  • klmasters by klmasters scientist, admin

    The computer search may have excluded those without redshifts - because as Carie points out you cannot tell why they are green if you don't have the redshift.

    Posted