Spiral arms

• by Ariaiyc_goingawayn0w

  It looks to me like the arms are overlapping at 6 o'clock. Can arms even do that?

  Posted November 5, 2015 12:56 AM

• by Ariaiyc_goingawayn0w

  #help with this please? I'm just very curious about this.

  Posted November 9, 2015 7:54 PM

• by JeanTate

  It certainly looks odd, doesn't it! 😃

  Here's what it looks like in SDSS:

  

  Myself, rather than spiral arms, I think there are at least two, incomplete, rings. Or perhaps at least one ring and one or two partial arms? Perhaps a zooite with many more classifications under their belt than I have could drop by and comment? Otherwise, I suspect only a detailed, quantitative analysis of the data (images are just data) is needed to work out what's going on.

  Can arms even do that?

  As far as I know, no they can't. However, it can sometimes be very difficult to work out what an 'arm' actually is, where it starts and where it ends, let alone decide its 3D structure (we see these features in projection, which can sometimes lead our brains to quite erroneous conclusions).

  Hope this helps, and happy hunting! 😄

  Posted November 9, 2015 8:14 PM

• by Ghost_Sheep_SWR

  http://imagine.legacysurvey.org/?ra=346.49562567628385&dec=0.8704975459292545&zoom=14&layer=decals-dr1j almost looks like 1 long, disturbed arm in residuals

  Posted November 9, 2015 8:35 PM

• by Ariaiyc_goingawayn0w

  Thanks, it just looked really strange to me.
  Thanks for the opinions, I did think that my perspective might be confusing it. As JeanTate said above, translating a 2D image to a 3D idea in our heads is a funny thing.

  Posted November 10, 2015 12:25 AM