Merger?
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The wavelengths (colours) of the two objects look similar which would suggest to me that they were the same distance, but could the off-centre one be a foreground star that is dying and therefore yellow/orange?
Posted
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by ElisabethB moderator
Hi Nemesis-of-the-vole and welcome to the Zoo
The central object, which you are supposed to classify is a disk or spiral seen edge on. The object, bottom right, is a foreground star from our galaxy
Happy hunting ! 😄
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by JeanTate in response to Nemesis-of-the-vole's comment.
Just to add to ElisabethB's excellent response ... in general, a deep yellow-orange color, in a star or a galaxy, may be an indication of 'old age', but sometimes the image processing goes a bit too far and the colors are artifacts.
In this image, the star has a funny pink/salmon edge, which is entirely an artifact.
In galaxies, yellow-orange often signifies not so much 'dying stars' as a lack of young, massive stars (which tend to be blue), which are generally gone within a few (tens of) million years. While some stars in yellow-orange galaxies are indeed 'dying' (they've entered the red giant phase, pretty much a last gasp, before running out of fuel completely), the vast majority may not have even entered middle age.
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by Budgieye moderator
some reading about colours
Zooite Guide to SDSS Spectra
http://www.galaxyzooforum.org/index.php?topic=274815.0You can judge the distance of galaxies by their colours.
Colours of Galaxies in SDSS : Redshift chart
http://www.galaxyzooforum.org/index.php?topic=277142.0Posted