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This is great! I love to meander thru data like this trying to understand what I am looking at. I found a couple of things that are probably processing artifac

This is great! I love to meander thru data like this trying to understand what I am looking at. I found a couple of things that are probably processing artifacts from the spectral filtering and selection of colors. One of them is a bright blue dipping segment that looks out of place. I can see blue filter artifacts on many of the starbursts. This one is very coherent but only for a short interstellar distance. I have labeled it "2" on the linked screenshots. [0] The other odd duck is the one labeled "1" on the screenshots. It is a green artifact that is brighter and dipping opposite most of the other green artifacts in the starbursts. I understand there are likely to be multiple passes of coherence filters, median filters, etc so these are probably related to signal/noise ratio enhancements in the raw data. If you would like to see them for yourself I have included a couple of screenshots that will help locate them. So much of this appears to be made up of long segments of stars that may twist through space. The individual stars look to maintain an internally consistent spacing in some cases. I think in many of these the individual stars or points of light are widely separated but from our vantage point they look related. It is in some ways like using a flashlight to look at the dark sky from the inside of a curving windshield that has a lot of bug guts on it. There's a lot going on out there. [0]https://postimg.cc/gallery/WbFww2h https://postimg.cc/gallery/WbFww2h

binarystargazer 2mo ago
Most of the artifacts you see are actually asteroids. We don't take all the colors at once when making an image. The ccds just count photons that fall on them, so we have giant glass filters that allow specific wavelengths through. We then image the fields multiple times with multiple filters and then map the wavelengths of light into color images (see other post about trying to make them as perceptually correct as possible). However, because taking multiple images over time means that things which are changing (i.e. moving asteroids) not not appear at the same places when we combine them. Most of the time these time changing effects get filtered out in the combination step, but sometimes if they are bright enough, or persistent enough the make it through. As an FYI, you can right click in the sky viewer and it will show the coordinates of the object, and there is a button to copy a shareable link that will take anyone right to where you are looking in the sky.
- doodlebugging 2mo ago
  Thank you for this useful reply. I appreciate the description of image building using the glass filters. That makes sense to me. The asteroids seem like an imaging issue that would be difficult to deal with since they are likely near-field objects that are in motion relative to far-field objects. That would also explain some of the trails that one sees if the objects along that trail are the same object imaged over a multi-step process. I figured there had to be a way to get real coordinates so that people could do research but I was not bright enough to push the buttons to find that link and had to use the tool I hate - Snip & Sketch. I have a license for SnagIt and Greenshot on another workstation, either of which is better than S&S but that installation is inaccessible due to hardware issues. Thanks for helping to make it easier to use these images!

binarystargazer 2mo ago

Most of the artifacts you see are actually asteroids. We don't take all the colors at once when making an image. The ccds just count photons that fall on them, so we have giant glass filters that allow specific wavelengths through. We then image the fields multiple times with multiple filters and then map the wavelengths of light into color images (see other post about trying to make them as perceptually correct as possible). However, because taking multiple images over time means that things which are changing (i.e. moving asteroids) not not appear at the same places when we combine them. Most of the time these time changing effects get filtered out in the combination step, but sometimes if they are bright enough, or persistent enough the make it through. As an FYI, you can right click in the sky viewer and it will show the coordinates of the object, and there is a button to copy a shareable link that will take anyone right to where you are looking in the sky.

doodlebugging 2mo ago
Thank you for this useful reply. I appreciate the description of image building using the glass filters. That makes sense to me. The asteroids seem like an imaging issue that would be difficult to deal with since they are likely near-field objects that are in motion relative to far-field objects. That would also explain some of the trails that one sees if the objects along that trail are the same object imaged over a multi-step process. I figured there had to be a way to get real coordinates so that people could do research but I was not bright enough to push the buttons to find that link and had to use the tool I hate - Snip & Sketch. I have a license for SnagIt and Greenshot on another workstation, either of which is better than S&S but that installation is inaccessible due to hardware issues. Thanks for helping to make it easier to use these images!