Space Warps Talk

Any examples of red or yellow lensed objects to look at?

  • HelPer2 by HelPer2

    When I spot a sim. it says "can be yellow or red too" Are there any good examples of arcs or quasars in these colours?
    Thanks

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  • ElisabethB by ElisabethB moderator

    I'm looking for some examples. But it is not easy ! 😄

    Posted

  • Budgieye by Budgieye moderator

    There is a yellow quad quasar in the Spotter 's guide.

    Posted

  • HelPer2 by HelPer2

    Ahh, I was thinking that the lensed object, rather than the lensing object could be yellow or red. The one in the spotters guide is lensing by a yellow galaxy, of a blue quad quasar. Now I'm a bit confused, and I'll have to wait until I get the message in question again to check if I've misread it!

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  • Budgieye by Budgieye moderator

    Here is the yellow quad in the spotter's guide which is on the SpaceWarps homepage.

    http://spacewarps.org/#/guide.

    enter image description here

    enter image description here

    The spotter guides shows a red galaxy, about z=0.8, which is about a tenth of the way across the universe lensing a yellow quasar at about z=4, which is about a third of the way across the universe.

    If the quasar was further away, it would be red. If it was closer, it would be green.

    See

    The colours of lensing and lensed galaxies http://talk.spacewarps.org/#/boards/BSW0000002/discussions/DSW000044z

    and

    Colours of Galaxies in SDSS : Redshift chart http://www.galaxyzooforum.org/index.php?topic=277142.0

    Zooite Guide to Strong Gravitational Lenses http://www.galaxyzooforum.org/index.php?topic=275811.0

    strong text

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  • Budgieye by Budgieye moderator

    Here is a possible orange arc.

    If an arc is orange or red, then the lensed galaxy is at about z=0.4 or z=0.6 and the lensing galaxy must be closer, say z=2 and so it will be white or yellow with blue arms, and it will look bigger on the image, since it is closer

    poss

    http://talk.spacewarps.org/#/subjects/ASW0002k40 posted by bernmeister
    http://talk.spacewarps.org/#/subjects/ASW0002k40

    Posted

  • Budgieye by Budgieye moderator

    Here is Hall's Arc, a red arc (image from the SDSS telescope). The distances have been researched and published.

    http://arxiv.org/abs/astro-ph/0701383

    enter image description here

    red arc is a distance of z~0.6

    massive orange galaxy is a distance of z=0.44,

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  • HelPer2 by HelPer2

    Those are really good examples - thanks for that!

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