Big green dot

• by Ghost_Sheep_SWR

  The big, round green dot at three o'clock from the core, looking like a star.

  Hi CeciliaB,

  I can only see a clear green dot at 9 o'clock near nucleus, and that is visible in multiple SDSS bands and also in DSS2. To see it better in PanSTARRS deselect the z and y bands so the color image is g r i.

  But perhaps you mean the brownish thing at exactly 3 o'clock just above the small yellow star? Perhaps you can find it here. I have enlarged the image to 550 pixels, deselected y and z band and manually changed in the URL 'autoscale=99.5' to autoscale=95.0'.

  NGC 4102 PanSTARRS

  If not please let me know, maybe with coordinates?

  Posted May 25, 2017 12:08 PM

• by CeciliaB

  There it came up in the image from the link: A big star-like object to the left and close to the brownish thing and the small yellow star. Do you realise which object I mean now?

  Anybody can see that it is a star, but I can't understand why it didn't show up in the images with all the bands?

  The coordinates are: 181.57369 and 52.70884

  By the way SIMBAD labels it a galaxy. Must be wrong.

  Posted May 25, 2017 1:11 PM

• by Ghost_Sheep_SWR

  I suspect that it has to do with the standard PanSTARRS image size (240 pixels). If you put in the central galaxy coordinates in PanSTARRS and don't change the image size it will be too small and this object(s) fall outside of the image.

  Looks like two foreground stars to me, maybe binary but is always difficult to know; http://ps1images.stsci.edu/cgi-bin/ps1cutouts?pos=181.57369+52.70884&filter=color&filter=g&filter=r&filter=i&filter=z&filter=y&filetypes=stack&auxiliary=data&size=150&output_size=256&verbose=0&autoscale=99.500000&catlist=

  Posted May 25, 2017 1:38 PM

• by CeciliaB

  The problem is solved. Thank you 😃 I also think it looks like a double star.

  EDIT: I should have put the star coordinates in Pan- STARRS. Then I would have seen the star. Or changed the image size in Pan-STARRS, as you did. You learn something every day.

  Posted May 25, 2017 1:43 PM

• by Ghost_Sheep_SWR

  😃

  Posted May 25, 2017 2:40 PM

• by Budgieye moderator

  The PanSTARRS image, with double star at 3 o'clock.

  

  http://ps1images.stsci.edu/cgi-bin/fitscut.cgi?red=/data/ps1/node19/stps19.0/nebulous/03/8a/5491779789.gpc1%3ALAP.PV3.20140730.restack%3A2014%3A11%3A06%3ARINGS.V3%3Askycell.2377.017%3ARINGS.V3.skycell.2377.017.stk.3845477.unconv.fits&blue=/data/ps1/node19/stps19.0/nebulous/19/05/5456491377.gpc1%3ALAP.PV3.20140730.restack%3A2014%3A11%3A06%3ARINGS.V3%3Askycell.2377.017%3ARINGS.V3.skycell.2377.017.stk.3810732.unconv.fits&green=/data/ps1/node02/stps02.0/nebulous/b4/c3/5523893503.gpc1%3ALAP.PV3.20140730.restack%3A2014%3A11%3A06%3ARINGS.V3%3Askycell.2377.017%3ARINGS.V3.skycell.2377.017.stk.3885588.unconv.fits&x=181.573690&y=52.708840&size=1000&wcs=1&asinh=True&autoscale=99.750000&output_size=1024

  http://ps1images.stsci.edu/cgi-bin/ps1cutouts?pos=181.57369+52.70884&filter=color&filter=g&filter=r&filter=i&filter=z&filter=y&filetypes=stack&auxiliary=data&size=1000&output_size=1024&verbose=0&autoscale=99.500000&catlist=

  Posted May 26, 2017 7:13 AM

• by Budgieye moderator

  Hubble image, in a different orientation

  

  Posted May 26, 2017 7:22 AM

• by CeciliaB

  Thanks, Budgieye, for the beautiful pictures 😃 Very useful to know that one can choose such high pixels!

  Posted May 26, 2017 3:16 PM