mystery bubble

• by march3258

  this galaxy has a bubble like feature in this image and i just checked the sky server and there seems to be something can anyone explain what it is? http://skyserver.sdss.org/dr8/en/tools/explore/obj.asp?id=1237658203958804612

  Posted May 19, 2015 11:19 PM

• by Budgieye moderator

  Bubble feature is partly an artifact of image compression for transmission. Looks like a moon crater in comments doesn't it.

  Original dark feature is probably

  a area of bad pixels where some of the light was not collected. Look at the straight edges that are aligned with the pixel collection direction.

  or an artifact caused when a cosmic ray hit was removed and the damaged area "repainted".

  Or there may another galaxy being overlapped, but the image is not good enough to say for sure.

  

  

  http://skyserver.sdss.org/dr8/en/tools/explore/obj.asp?id=1237658203958804612

  run 2964
  rerun 301
  camcol 2
  field 80

  ---

  In dr7

  

  http://cas.sdss.org/dr7/en/tools/explore/obj.asp?id=587732482733899934

  same image data, I believe, just processed differently

  run 2964
  rerun 40
  camcol 2
  field 80

  Posted May 20, 2015 5:29 AM