Interesting object

https://www.legacysurvey.org//viewer/?ra=61.4534&dec=-6.3237&layer=ls-dr9&zoom=15

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:person_raising_hand: HI!

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18 views. My guess is people (I include myself) aren’t sure what it is. It is very cool though.

My stab in the dark is a possible stellar stream although I’m not exactly sure.

Either way it’s got to be some material from the galaxy that has been pulled off it right? Can’t see it being anything else.

Hmm, it looks like quite a dense medium. Could be ram pressure stripping, though it looks weirdly spiral.

I’m -1 on both RPS and a galaxy source for the hydrogen
RPS is directional and why wouldn’t a galaxy make stars internally?

I like a flow - medium to high density of hot or cold H maybe H+

I’m still fuzzy as to where the dark mater halo for an elliptical would be but if you fiddle with the C & B (I’m using C=1.3 B=0.8) and DR9/10 you can see a tenuous bridge connecting the 2 halves of the blue spiral.if the spiral is rotating in a mass that fixes the gas in place or there are resonance effects then there might be compressing for star making.

I’m kind of talking out of my hat here, but that is the direction I’d ask Qs in.

Agreed. Not sure what sort of motion could RPS something in that manner so don’t think RPS.

Literature says it is Sy1 which is interesting. There are a number of references to this galaxy (including by good old William Keel). I’m going to try to summarise what the good sources say below. A full list is linked here.

  1. Source 1: “The Galaxy Zoo survey for giant AGN-ionized clouds: past and present black hole accretion events”. Looks like this might be the explanation.
  2. Source 2: This galaxy is referenced in a paper announcing the discovery of a new lensed quasar although it is not the quasar in question. The paper used a near-UV excess method to find lensed quasar candidates. Although this paper is attached to this galaxy in NED, there is no mention of this galaxy in the paper. However, it is interesting to note that this galaxy does have a UV source, although I can’t see the data on whether it is from the near or far band of GALEX. More details on this method here.
  3. Source 3: Assorted papers analysing black holes and their mass functions
  4. Source 4: Assorted papers analysing Sy1s and AGNs

It would make most sense to me for it to be an ionised gas cloud caused by the AGN so I reckon that would be interesting.

Side note: if anyone knows how to access what bands of GALEX that UV signal is in I would be most grateful.

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Ok so let’s assume a hungry black hole and a well-stocked core buffet

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The Galaxy Zoo survey for giant AGN-ionized clouds: past and present black hole accretion events, Keel+, 2012 has it listed as H II region in Table 3, so by that account it isn’t an Voorwerpje / EELR confirmed by spectrum, more likely is starforming streams, mimicking spiral arms?

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