NGC 5945 - pretty eyeliner

I like how in NUV it is as though the bar doesn’t even exist. Rather it tracks a ring of star formation around the galaxy, and then the most blue portions around the galaxy also follow a NUV/FUV spectrum, I suppose related to star formation. So I guess the thing I find interesting about this, besides just how pretty this little formation is, is how there seems to be disallowed regions of star formation. Take a look in the NUV and FUV! [In the Galex layer Near-UltraViolet is yellow, and Far Ultra Violet is blue] Galex - Galex Evolution Explorer
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1350-1750 Å NUV
1750-2800 Å FUV
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https://www.legacysurvey.org//viewer/?ra=232.4367&dec=42.9195&layer=ls-dr9&zoom=14

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Yeah, that’s always cool to me, how the UV tracks hot new stars and visible light is more from old stars just livin’ their lives

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Another that shows a similar pattern
https://www.legacysurvey.org/viewer/?ra=226.7830&dec=1.5447&layer=galex&zoom=13
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NGC1300
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However, now one with a totally different pattern.

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Idk I think that’s caused by this one not being as big as the others, thus the signal from GALEX not having enough resolution. I’m not sure though

https://www.legacysurvey.org//viewer/?ra=47.9760&dec=-2.5669&layer=ls-dr8&zoom=15

cuz when we go to the NGC barred spirals… NGC1512


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We back to normal:)
They really look like ring galaxies under this light don’t they?

Is that yellow dot in there the nuclear star cluster or activity of the blackhole? I know there is star-formation around the dense center, but there is star formation all across the arms… is that gray stuff just a composite, or?


Check out the Very Large Array VLASS on this one!
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Got some ringworm going on there never seen that before. NGC1097
An AGN with a circumnuclear ring, oh they say it tracks star formation. But if it tracks star formation, why not so yellow along the blue arms? Density of galex signal, some of them do these dark blue stuff, others yellow, and others whitish gray. But I think the Galex makes the nucleus really prominent.

I looked into the circumnuclear ring here and actually SOFIA has an image of its magnetic field lines - take a look. It has two magnetic fields, but this is the spiral magnetic field inflowing gas into the center.

I really have never seen that kind of radio signal, I wonder why they so quickly explain it, and you don’t get the same kind of radio signal in ring galaxies.

The Cartwheel Galaxy - no nucleus? No radio signal (not out of the ordinary)
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In the purple Image, the white dots are thought to be black hole binaries, feeding and producing xrays.
https://chandra.harvard.edu/edu/formal/cartwheel/

NGC 1291


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I like how the center of ring galaxies look like elliptical galaxies, but still if you turn on the VLA for this, and many others, ring galaxies I mean, starbursting rings don’t really read on the radio, but maybe they need to be more dense, but many galaxies should have circumnuclear starbursting rings around their nucleus, just like the milky way. Why doesn’t the VLA find the circumnuclear rings? Are the circumnuclear rings a progenitor step to quasars? Maybe the circumnuclear ring is a quick step before a jet. Ultraluminous Infrared Galaxies and the Origin of Quasars - NASA/ADS

All for now! But if anyone sees anymore galaxies with circumnuclear rings I would be really fascinated in having a look!

i don’t have much to add but this thread was a great read

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