Disk Detective Talk

Object that's bright in WISE 3 and 4.

  • Artman40 by Artman40

    This object has SED diagram similar to a star. However, this image lights up in WISE 3 and 4. What can cause that? There weren't any good references in SIMBAD either as the only one I found was made prior to WISE launch.

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  • Pini2013 by Pini2013 translator, moderator in response to artman40's comment.

    α Vir (Aurora) near , all is bright around it 😃

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  • Artman40 by Artman40

    How many screens away is the star?

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  • Pini2013 by Pini2013 translator, moderator in response to artman40's comment.

    α Vir: 13h25m11.60s -11°09'41.0" and IRAS F13219-1102: 13 24 33.7 -11 17 55, go here http://irsa.ipac.caltech.edu/data/DSS/ to see it or download and image from http://archive.eso.org/dss/dss (change the size xy)

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  • Artman40 by Artman40

    Distance to Spica is 260±20ly. How large object it has to be resolved in WISE 4 while being quite a few pixels wide while being at that distance?

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  • lrebull by lrebull scientist, translator, admin

    This blog post has quite a few words on the subject of disks and spatial resolution: http://blog.diskdetective.org/2014/02/20/thats-no-moon/ 😃 In sum, NONE of the known objects with disks are resolved in WISE. The reason the star appears to be quite a few pixels wide is a result of the telescope+detector's response to a tiny point of light. MANY more words in that post ...

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  • Artman40 by Artman40

    This must be really bright in that kind of infrared to saturate so many pixels. Could it be an extragalactic object?

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  • lrebull by lrebull scientist, translator, admin

    As it says back at the beginning of this chain, the overall background brightness at the longest wavelength bands is kind of "spillover" from a relatively nearby very bright star. 😃

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  • Artman40 by Artman40

    Is there any way to see the whole "spillover" image?

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  • marckuchner by marckuchner scientist, admin

    Try this tool: http://irsa.ipac.caltech.edu/applications/finderchart/

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  • Artman40 by Artman40

    Too bad I can't use this due to software issues. How does Sirius look in all the images in comparison? I've also noticed that WISE 1 and 2 act a bit differently when displaying images from WISE 3 and 4.

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  • lrebull by lrebull scientist, translator, admin

    Why can't you use that tool? What software issues? It shouldn't require any software installation.

    Sorry, what? What do you mean "WISE 1 and 2 act a bit differently when displaying images from WISE 3 and 4"? When displaying WISE 3 or 4, you shouldn't be able to see WISE 1 or 2 at the same time within Disk Detective, so how is it acting differently?

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  • lrebull by lrebull scientist, translator, admin

    You can also get WISE images via this tool: http://skyview.gsfc.nasa.gov/current/cgi/titlepage.pl
    but you do have to be careful because you can inadvertently resample the images a lot, which could change what you see.

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  • Artman40 by Artman40

    In WISE 1 and 2, if there is another bright object nearby, the object under crosshairs is more contaminated while in WISE 3 and 4 it's not the case. Anyway, how do brightest stars affect the WISE 3 and 4 images?

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  • lrebull by lrebull scientist, translator, admin

    Ah, now I understand your question! The images are scaled by the brightest thing in the image. So when there is a very bright source, the color scale is such that you mostly only see the other brightest things. When there is no very bright source, you see more of the noisy texture of the background in the image.

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  • Artman40 by Artman40

    Thanks. This helps and explains a lot!

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