Galaxy Zoo Talk

Given coordinates, or an SDSS ID, how to find the AGZ ID(s), if there is one?

  • JeanTate by JeanTate

    The forward part is easy; for example, Image AGZ0003oop contains this text under the image*:

     SDSS
 RA: 84.3998833514936, DEC: 1.33445114191412

    What about the reverse? What if I know the coordinates (RA: 84.39988, Dec: 1.33445) and/or the SDSS ID (found by clicking on the "View in SkyServer" link; J053735.97+012003.9 - which is, of course, ~the coordinates in Sexagesimal) and want to find AGZ0003oop (and any other AGZ images/fields which include SDSS J053735.97+012003.9)?

    Can that be done, by an ordinary zooite? Or is it something only someone who has 'SCIENTIST' powers^ can do?

    *when you click on the "Galaxy Zoo examine" link, the AGZ ID is given, confusingly, as AGZ0003OOP; the AGZ IDs do not contain upper case characters (except for "AGZ")

    ^ETA: To be clear, I'm referring to those with the title SCIENTIST

    Posted

  • klmasters by klmasters scientist, admin

    Turns out this is hard for scientists to do as well! 😉 Perhaps a suggestion for future versions of talk. If someone else has tagged the image with RA and Dec or other identifier you would be able to find it perhaps, but that relies on human input of those values…

    Maybe this is a job for Zoonibot to go through and tag all images with RA and Dec….

    Posted

  • KWillett by KWillett scientist, admin, translator

    It's also the functionality that we've been trying to build in to zootools. You can do a search for RA/dec for SkyServer data there; it might be useful to implement a similar search for the Zooniverse subjects as well.

    We know this has been asked about other projects (such as Radio Galaxy Zoo), and it looks like this is a useful function we should try to build into the next version of Talk. Unfortunately, it's not a simple search to implement right now from the development standpoint.

    Posted

  • Budgieye by Budgieye moderator

    Can the zoobots also automatically look up the dr7 number?
    And put on the SDSS number?

    Posted

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

    Thanks klmasters, KWillett! 😃

    Perhaps a suggestion for future versions of talk.

    Just such a suggestion was made, ~five months' ago.

    We know this has been asked about other projects (such as Radio Galaxy Zoo), [...] Unfortunately, it's not a simple search to implement right now from the development standpoint.

    In RGZ I showed that there is a method, a fairly simple one, for the purpose I intended (given a source, find at least one ARG ID which contains the source, if it exists; spend no more than a few minutes doing this). Whether that method would work for AGZ IDs, here in GZ, I do not know.

    Posted

  • vrooje by vrooje admin, scientist in response to JeanTate's comment.

    I haven't been on casjobs in a while; is it not possible to do this for published GZ2 classifications using that? Or just downloading the table? Admittedly it's a pretty big table...

    Posted

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

    Hmm, ... I just checked, and there does not appear to be anything like an ARG ID in any GZ2 table.

    Yes, if there were a table containing DR7ObjId or DR8ObjId or (RA, Dec) AND an ARGId, it would be fairly straight-forward (though likely not possible in ordinary spreadsheets, given how big the table would be); assuming the source for which you're trying to find a match exists in such a table. However, I know of no such table.

    Use of such a table would work for Budgieye's question though:

    Can the zoobots also automatically look up the dr7 number? And put on the SDSS number?

    One way to find something like this is to use the SDSS CrossID for DR7 and SDSS CrossID for DR8 tools (I don't know if there's also one for DR9 or DR10).

    Posted

  • klmasters by klmasters scientist, admin

    I think we didn't realise that people might was the AGZ number - it's simply an internal Galaxy Zoo number to ID the classifications (and to some extent deliberately obscure the galaxy ID at the point of classification, since we like to assume all classifiers are independent, so we don't want people looking up other people's classifications and just inputting those!).

    SDSS objids were the same from the EDR until DR7, and then the new imaging which was done for SDSS-3 was added in and the entire source finding algorithm was rerun, making the new DR8 objids which there are no plans I'm aware of to change in future Drs (so DR8, DR9, DR10 all have same objids). Confusing I know, but the source selection was so completely reworked it was felt necessary.

    I think @kwwillett might be working on making Zoonibot tag galaxies with RA and Dec (along with everything else he does for Galaxy Zoo).

    Posted

  • c_cld by c_cld

    The search function has to work on the SDSS objid part of the image link as in GZ forum, otherwise "talk" will stay behind for more than two years now...

    Posted

  • Budgieye by Budgieye moderator

    Obsolete ObjID Yes, it is annoying that most of the Forum posts use the DR7 number (58............) which is now out of date. I suppose the DR8 number (12............) will probably go out of date too. So really, we must use the SDSS J...+... number.

    I was thinking that I would like the AHZ... number if I started a Lens file - look up known lenses and find the AHZ... number. Though if all Object ID numbers get connected by a Zoonibot, then that would be another way to do it.

    Posted

  • elizabeth_s by elizabeth_s in response to Budgieye's comment.

    Hmmm question here what is a Zoonibot?

    Posted

  • vrooje by vrooje admin, scientist in response to Budgieye's comment.

    Strangely enough I don't think the SDSS catalogue number (J number) is easily searchable on the SDSS website... you have to break up that number into coordinates and you may even have to convert the coordinates into decimal numbers, which is a bit more work than just putting in an object ID. And for a lot of objects NED will have multiple SDSS IDs for the same object, so even that isn't perfect.

    Posted

  • vrooje by vrooje admin, scientist in response to elizabeth's comment.

    Zoonibot is a type of program called a "bot", written originally for Planet Hunters Talk, to help answer basic questions (where a computer could recognize that a question was being asked) by just defining terms.

    We've tried letting Zoonibot post here on GZ Talk once or twice, but it's still a work in progress and definitely not finished yet. I think it could potentially do a lot, at least eventually!

    Posted

  • elizabeth_s by elizabeth_s in response to vrooje's comment.

    Oh! Then a much better thing than the spammer bots. Good to known. Thanks

    Posted

  • klmasters by klmasters scientist, admin

    Objids aren't really out of date - they're all recorded in the data base.

    The issue is there isn't a 1-1 link between DR7 and DR8 - because many galaxies which were shredded in DR7 were not in DR8 (and for all the other reasons automated source finding fails sometimes).

    Posted

  • elizabeth_s by elizabeth_s in response to klmasters's comment.

    Shredded?? why where they shredded? search has been a problem since the start. but shredded. I don't get it. sorry.

    Posted

  • klmasters by klmasters scientist, admin

    Oh sorry - astronomy term. Shredded means that big galaxies in the initial source finding for SDSS were sometimes split up into 2 or more "sources" (which are actually the same thing). You can see this when sometimes big galaxies are not correctly centred in the images we show in GZ. The new source finding in DR8 didn't completely fix this, but did improve it.

    Posted

  • Budgieye by Budgieye moderator in response to vrooje's comment.

    Yeah, I know. It is a bit of effort to find if some one has already written up about a "pea" or whatever in the forum. I was just hoping for an easy solution...sigh...

    Posted