The image size of this camera is unbelievably huge in its coverage.
Most telescopes take pictures of objects - this one takes pictures of the entire sky. And will do so in a time-lapse fashion for 10 years.
It's simultaneously more in line with a human's experience than an obscure wavelength of tiny object not visible to the naked eye - it takes a high-resolution picture that's similar to what you'd see if you look at the sky. But it's also profoundly grand beyond a human's experience because of just how much stuff is collected.
This is tricky to navigate because most of the sky survey hasn't happened yet. You need to zoom way out and look for patches that are mostly, but not completely black. And that gives you an idea of how huge the map will be once they've filled more of it in.
Presumably it will get easier after more of the survey is done, but having a list of bookmarks instead of just one might be nice?
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.
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.
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!
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[ 3.3 ms ] story [ 20.0 ms ] threadMost telescopes take pictures of objects - this one takes pictures of the entire sky. And will do so in a time-lapse fashion for 10 years.
It's simultaneously more in line with a human's experience than an obscure wavelength of tiny object not visible to the naked eye - it takes a high-resolution picture that's similar to what you'd see if you look at the sky. But it's also profoundly grand beyond a human's experience because of just how much stuff is collected.
https://skyviewer.app/explorer
Presumably it will get easier after more of the survey is done, but having a list of bookmarks instead of just one might be nice?
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
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.
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!