Space Warps Talk

What would cause this arc?

  • Traumat by Traumat

    Obviously new here, hence the newbie confusing question
    Is it natural to have an arc as (i see) in this image? I see in the non-lens examples arcs and circles but they appear faint. This one does not have what I describe as a (core) to which there is a galaxy to lens the blue arc I see. I does just appear to be a group of galaxies together but the arc is confusing me.

    Posted

  • ElisabethB by ElisabethB moderator

    Hi Traumat

    Groups of galaxies can also produce lenses.

    When I first saw this image, I thought it was a sim, with the well defined arc and counter image. But it's not a training image.

    Looks interesting.

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  • Traumat by Traumat

    Thanks ElisabethB for the quick response
    I've been digging through the posted images to find similar ones with no luck.

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  • Tom_Collett by Tom_Collett scientist

    This is a very interesting image. The configuration of the blue light looks just like what would be expected for a lensed background source. But the red light isn't in the centre of the blue.

    I confess I don't know what to make of this. It could be a coincidental alignment of blue objects; it could be that there is lots of 'dark' matter off to the left of the lens (in this case I simply mean matter that isn't emitting in the optical); or it could be that the two galaxies (red and brown) are combining to produce a really interesting lensing geometry.

    I'm leaning towards coincidence - but if it is a real lens it's a very cool one.

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  • Traumat by Traumat

    Excellent!
    Thank you so much for the feedback. It makes the search so much more satisfying and gives you the feeling that you're making a difference.

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  • Capella05 by Capella05 moderator in response to Tom Collett's comment.

    Is it possible that simulated lenses are being introduced without the 'Training Image' tag? In this case a bad sim?

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  • Tom_Collett by Tom_Collett scientist in response to Capella05's comment.

    I don't know, but if this is a sim the arcs aren't really in the place you'd expect them. It almost looks like a simulation that has been put on the wrong image (in which case the red light is a coincidence), I don't know if that's a bug seen before.

    Hopefully it's not a simulation bug. If this object is really on the sky I'm intrigued by it.

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  • Traumat by Traumat

    Well you must keep us advised of your findings please. My curiosity shall get the best of me on this one.
    Thanks Ted

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  • anupreeta by anupreeta scientist, admin

    Sorry for all the fuss over the sim image which is not labelled. There are a few of them which were not labelled and injected I have requested the tech team to add this info. Hopefully, they will get working on it soon!

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  • Capella05 by Capella05 moderator in response to anupreeta's comment.

    Thanks @anupreeta - must admit this image did have us confused!

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  • ElisabethB by ElisabethB moderator

    Tx Anu !

    So, we've got some rogue sims on our hands ! 😄

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  • Traumat by Traumat

    Thanks for the update! At least were catching them, sims or not!

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  • Tom_Collett by Tom_Collett scientist

    Ah boo. This would have been such a cool object.

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