4 ms·

Spanish astronomer discovers new active galaxy

80 points by wglb 3y ago

deleted 3y ago
[deleted]
hshdhhr 3y ago
+1 for the name
martinclayton 3y ago
Chapeau for this discovery! Appears to be by a non-professional astronomer, using public HST data, wonderful.
canvascritic 3y ago
This is awesome! Finding an AGN within the halo of a galaxy, especially one as well-studied as the sombrero galaxy, is a bit like discovering a hidden room in a house you've lived in for years. it reshapes our understanding and invites us to question our observational techniques and tools. also: barred spiral galaxies like the Iris are super neat. If I'm not mistaken (I'm only casually interested in astronomy, not a professional) bar structure is thought to play a crucial role in galactic evolution, funnelling gas towards the center and potentially feeding the AGN. the discovery of an AGN in such a context could shed light on the interplay between galactic morphology and central activity.
- angiosperm 3y ago
  If it's really at 65 million light years, it's no satellite at all.
  - ben_w 3y ago
    I don't think anyone's claiming that it is a satellite; it's only "in the halo" visually, but the new one further from the Sombrero than we are.
hpcjoe 3y ago
So I pulled up my jpg of the Sombrero galaxy to see (its been my laptop background for a few years). I could barely make out Iris in it. Absolutely awesome though! Something about the deep field and ultra deep field pictures that makes me happy. Also makes me wonder about how many beings in these other galaxies look out, see Milky Way colliding ever so slowly with Andromeda in their own deep field views.
hsjqllzlfkf 3y ago
Why is the fact that the person is Spanish relevant enough to merit being included in the headline?
- martinclayton 3y ago
  I think it's just a headline writer thing. Searching for "astronomer discovers" it appears there's often an "extra" word. When it's a plurality of astronomers doing the discovering, less so.
  - deleted 3y ago
    [deleted]
  - hsjqllzlfkf 3y ago
    Somehow I don't think they would've written the headline "american astronomer discovers..." If the person had been american. To me it kind of seems like "oh look Spanish people trying to do science, so cute".
    - doctor_eval 3y ago
      They would probably write “Illinois astronomer discovers”.
    - foobarian 3y ago
      It’s an entropy thing. You don’t write the sun rose in the east, but if it rose in the west that would contain more information.
    - BeetleB 3y ago
      I think if an American discovered it, and you were reading a Spanish news site (originating from Spain, targeting Spanish citizens), it would not surprise me if the title were "American astronomer discovers ..."
      - anthk 3y ago
Keysh 3y ago
Sadly, this is a case of mistaken identity. I downloaded a Hubble Legacy Atlas mosaic image of the Sombrero Galaxy, and found his galaxy ("Iris"), right where he said it was. From the appearance (and the color figures in his paper), it's a nice strongly barred spiral (something I study a lot). Given the very small angular size (roughly 4 arc seconds in diameter), it's probably hundreds of megaparsecs (well over a billion light years) or more away, and so not associated with the Sombrero Galaxy (which is at a distance of only 9 or 10 megaparsecs). The object is not in the NASA Extragalactic Database (not surprising for something so mall and distant). If you search near its position in Simbad, you do indeed get "PSO J190.0301-11.6124" (listed as "globular cluster candidate"), just as he found -- but it's crucial to note that the latter object's position differs by about nine arc seconds from the position of the "Iris" galaxy. If you look at the Hubble image, you can see a compact, slightly elliptical object at the position of PSO J190.0301-11.6124; its appearance is consistent with being a "globular cluster candidate" associated with the halo of the Sombrero Galaxy. But all the deductions about possible distances, spectral energy distributions, etc., are vitiated by the misidentification. So while this is a galaxy, it's way, way beyond the Sombrero Galaxy, and I doubt the claimed X-ray source association, so it's probably not an active galaxy. (Well, it could be, but we probably don't have any evidence for that.)
- Apocryphon 3y ago
  [flagged]
  - Keysh 3y ago
    Not sure if this was addressed to me, but in case it was: I actually did my Ph.D. thesis on double-barred galaxies, and have continued to work on and off on barred galaxies over the years; here's a partial list of paper's I (Peter Erwin) have authored or co-authored on the subject: https://ui.adsabs.harvard.edu/search/fq=%7B!type%3Daqp%20v%3D%24fq_database%7D&fq=%7B!type%3Daqp%20v%3D%24fq_property%7D&fq_database=database%3A%20astronomy&fq_property=property%3A%20refereed&q=author%3A(%22erwin%2C%20p%22)%20abs%3A(barred)&sort=date%20desc%2C%20bibcode%20desc&p_=0 https://ui.adsabs.harvard.edu/search/fq=%7B!type%3Daqp%20v%3...

80 points by wglb 3y ago

deleted 3y ago

[deleted]

hshdhhr 3y ago

+1 for the name

martinclayton 3y ago

Chapeau for this discovery! Appears to be by a non-professional astronomer, using public HST data, wonderful.

canvascritic 3y ago

This is awesome! Finding an AGN within the halo of a galaxy, especially one as well-studied as the sombrero galaxy, is a bit like discovering a hidden room in a house you've lived in for years. it reshapes our understanding and invites us to question our observational techniques and tools. also: barred spiral galaxies like the Iris are super neat. If I'm not mistaken (I'm only casually interested in astronomy, not a professional) bar structure is thought to play a crucial role in galactic evolution, funnelling gas towards the center and potentially feeding the AGN. the discovery of an AGN in such a context could shed light on the interplay between galactic morphology and central activity.

angiosperm 3y ago
If it's really at 65 million light years, it's no satellite at all.
- ben_w 3y ago
  I don't think anyone's claiming that it is a satellite; it's only "in the halo" visually, but the new one further from the Sombrero than we are.

hpcjoe 3y ago

So I pulled up my jpg of the Sombrero galaxy to see (its been my laptop background for a few years). I could barely make out Iris in it. Absolutely awesome though! Something about the deep field and ultra deep field pictures that makes me happy. Also makes me wonder about how many beings in these other galaxies look out, see Milky Way colliding ever so slowly with Andromeda in their own deep field views.

hsjqllzlfkf 3y ago

Why is the fact that the person is Spanish relevant enough to merit being included in the headline?

martinclayton 3y ago
I think it's just a headline writer thing. Searching for "astronomer discovers" it appears there's often an "extra" word. When it's a plurality of astronomers doing the discovering, less so.
- deleted 3y ago
  [deleted]
- hsjqllzlfkf 3y ago
  Somehow I don't think they would've written the headline "american astronomer discovers..." If the person had been american. To me it kind of seems like "oh look Spanish people trying to do science, so cute".
  - doctor_eval 3y ago
    They would probably write “Illinois astronomer discovers”.
  - foobarian 3y ago
    It’s an entropy thing. You don’t write the sun rose in the east, but if it rose in the west that would contain more information.
  - BeetleB 3y ago
    I think if an American discovered it, and you were reading a Spanish news site (originating from Spain, targeting Spanish citizens), it would not surprise me if the title were "American astronomer discovers ..."
    - anthk 3y ago

Keysh 3y ago

Sadly, this is a case of mistaken identity. I downloaded a Hubble Legacy Atlas mosaic image of the Sombrero Galaxy, and found his galaxy ("Iris"), right where he said it was. From the appearance (and the color figures in his paper), it's a nice strongly barred spiral (something I study a lot). Given the very small angular size (roughly 4 arc seconds in diameter), it's probably hundreds of megaparsecs (well over a billion light years) or more away, and so not associated with the Sombrero Galaxy (which is at a distance of only 9 or 10 megaparsecs). The object is not in the NASA Extragalactic Database (not surprising for something so mall and distant). If you search near its position in Simbad, you do indeed get "PSO J190.0301-11.6124" (listed as "globular cluster candidate"), just as he found -- but it's crucial to note that the latter object's position differs by about nine arc seconds from the position of the "Iris" galaxy. If you look at the Hubble image, you can see a compact, slightly elliptical object at the position of PSO J190.0301-11.6124; its appearance is consistent with being a "globular cluster candidate" associated with the halo of the Sombrero Galaxy. But all the deductions about possible distances, spectral energy distributions, etc., are vitiated by the misidentification. So while this is a galaxy, it's way, way beyond the Sombrero Galaxy, and I doubt the claimed X-ray source association, so it's probably not an active galaxy. (Well, it could be, but we probably don't have any evidence for that.)

Apocryphon 3y ago
[flagged]
- Keysh 3y ago
  Not sure if this was addressed to me, but in case it was: I actually did my Ph.D. thesis on double-barred galaxies, and have continued to work on and off on barred galaxies over the years; here's a partial list of paper's I (Peter Erwin) have authored or co-authored on the subject: https://ui.adsabs.harvard.edu/search/fq=%7B!type%3Daqp%20v%3D%24fq_database%7D&fq=%7B!type%3Daqp%20v%3D%24fq_property%7D&fq_database=database%3A%20astronomy&fq_property=property%3A%20refereed&q=author%3A(%22erwin%2C%20p%22)%20abs%3A(barred)&sort=date%20desc%2C%20bibcode%20desc&p_=0 https://ui.adsabs.harvard.edu/search/fq=%7B!type%3Daqp%20v%3...