Star, but fuzz around it
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Budgieye
moderator
Star in front of galaxy and spectrum taken. Redshift is zero. Is spectrum a blend of galaxy and star?
http://skyserver.sdss.org/dr9/en/tools/explore/obj.asp?ra=200.5677&dec=56.70025
http://cas.sdss.org/dr7/en/tools/explore/obj.asp?id=587735696447439031
http://skyserver.sdss.org/dr9/en/get/specById.asp?id=1486306670576429056
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Ghost_Sheep_SWR
in response to Budgieye's comment.
I suck at reading spectra, but likely yes. More info in NED, there are three wildly varying redshifts given. One based on absorption lines, one on emission lines and the top one on both. Likely a blend of star + galaxy, or three objects (3 different redshifts);
Interested in expert opinion
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mlpeck
in response to Budgieye's comment.
Is spectrum a blend of galaxy and star?
Yes:
Top pane is a model fit to the rest frame galaxy spectrum (adopting the NED value of z=0.1465) with a library of SSP models plus a small library of stars at redshift 0.
The third pane is the estimated contribution of the galaxy model, while the 4th is the estimated stellar contribution. Wavelengths are in the galaxy rest frame, and the star spectrum is therefore artificially blue shifted. So for example the prominent absorption line at ∼5200Å is NaD (actual wavelength ∼5892Å).
The star contributes about 65% of the light over the whole spectrum.
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Ghost_Sheep_SWR
in response to mlpeck's comment.
That is really helpfull and very cool!
Although wondering how it is possible there is also a redshift of z = 0.631804 +/- unc. 0.005562 based solely on emission lines in NED?
http://ned.ipac.caltech.edu/cgi-bin/datasearch?search_type=z_id&objid=3468076&objname=2MASX J13221624%2B5642004&img_stamp=YES&hconst=73.0&omegam=0.27&omegav=0.73&corr_z=1&of=table#No3
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Budgieye
moderator
What an excellent explanation mipeck. Thank you, I will put a link to it in the Index. 7.1 Spectral Charts, MaNGA https://talk.galaxyzoo.org/#/boards/BGZ0000001/discussions/DGZ0000wrb?page=7
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