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wimvb

Faint structure around ngc 2841

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While clouded in and waiting for knee surgery, I started playing with data from the Liverpool Telescope (http://telescope.livjm.ac.uk/). I downloaded all the NSO data on NGC 2841, a very nice flocculent galaxy in Ursa Major, and started processing in PixInsight. While I couldn't get anywhere with the colour of this galaxy, the luminance created from the combined filters revealed structures that I've never seen before in an image of this galaxy.

I combined a colour image of NGC2841 with an inverted superstretch of  the combined SDSS-r, Bessell-V, and Bessell-B filters.

RGB image:

  • Red: 35 frames SDSS-r'
  • Green: 16 frames Bessell-V
  • Blue: 20 frames Bessell-B

L image:

integration of all 71 frames, approximately 100 minutes total exposure time. Field size: roughly 10 x 10 arcminutes.

ngc2841_ext2.thumb.jpg.c540867f5f2f2429953bd5cb7df0682a.jpg

The arrow points at a weak loop, and the circle shows a slight density increase in the weak structure.

ngc2841_ext.thumb.jpg.e03a18063de8b29c36c4c712f894e695.jpg

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Interesting.  Without the non inverted image though its hard to tell what these features might be.  Obviously you feel they are not the typical edges of normal galaxy features--but that is a tough one without the regular image

Rodd

 

Edit:  I see now the regular image inside the oval--it would still be good to see the normal image of teh areas in question though--definitely not the edge of the disc, though

Edited by Rodd

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I just stumbled across this article by the Dragonfly team

https://scholar.google.com/scholar?start=20&q=Ngc2841+galaxy&hl=sv&as_sdt=0,5#d=gs_qabs&u=%23p%3DWjSypV0skbIJ

It seems that the structures extend a lot further out than what is visible in the 100 minutes exposure that I processed. Cool! 

I wonder how deep amateur gear would allow one to image this object. Maybe a challenge for galaxy season? 

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