Space Warps Talk

Lens top right red quasar?

  • Againstmethod by Againstmethod

    Is this just a coincidental alignment or is it a lens? I have examined it in dashboard and it looks like it could be a lens to me (very symetrical, and color for both red dots looks identical to me) but I could be completely wrong.
    For this type of objects I sometimes have a hard time distinguishing stars from galaxies .

    From the information I found I would say it if it is a lens it would have to be a quasar (double point like image is a typical quasar lens according to the info in the spaghettilens topic, a lensed galaxy would be more likely to form an arc on one side if it is a double image) but that would mean a quasar at very high redshift while the lensing galaxy is much closer. On the other hand the two dots look slightly elliptical to me. From Budgieye's color vs redshift topic (thanks Budgieye!) that would mean either:

    Lensing Galaxy aproximately z=0.4~0.6
    Lensed Quasar aproximately z=5.4
    Is such a large distance between a lens and a lensed object even possible?

    or

    Lensing Galaxy aproximately z=0.4~0.6
    Lensed Galaxy aproximately z=0.6~0.8

    Or of course complete failure:

    Chance alignment of stars/galaxies 😛

    Any input welcome!

    Posted

  • Budgieye by Budgieye moderator

    You are welcome 😃 I like the chart too, because I like making things easier. But then it starts getting complicated again. 😦

    enter image description here

    http://talk.spacewarps.org/#/subjects/ASW0006mme

    The only was to be sure of identifications is to do a spectral chart, and of course that isn't going to happen. So here are my guesses.

    Your first guess: red galaxy and red lens. The lensed galaxy has to be about twice the distance of the lensing galaxy. This would mean that the more distant galaxy would have to be considerably more red than the lensing galaxy, due to redshift. These both look the same colour of orange. Orange galaxies are close enough that we should be able to see enough structure in them to know that they are galaxies, not stars.

    enter image description here

    http://cas.sdss.org/astro/en/tools/explore/obj.asp?id=588017627222573280 This orange galaxy is from the Sloane telescope,SDSS, so the image will be fuzzier than in our images, but the colour is still the same.

    .Also then, the distant lensed galaxy would form arcs, not quasar points. Admittedly, some arcs are very short, and sometimes the arcs can look like quasar points.

    Second guess: red galaxy and red quasar points.

    Here is a red quasar on SDSS
    http://cas.sdss.org/astro/en/tools/explore/obj.asp?id=587727180613353723

    They can be orange too.

    enter image description here

    So the orange objects could be quasar points. But once again, the orange galaxy should be larger.

    I like your last guess stars or chance alignment. Looking at the central object, I think it is a orange-red star. It looks perfectly round, and has that diffraction ring around the edge that stars seem to have on CFHT images. With two stars nearby, either a chance alignment or possible distant trinary star system.

    http://www.galaxyzooforum.org/index.php?topic=274815.msg300405#msg300405 Zooite guide to spectra

    http://www.galaxyzooforum.org/index.php?topic=277142.0 Colours of galaxies redshift chart

    Posted

  • Againstmethod by Againstmethod

    Thanks Budgieye!

    Posted