Looks like objects orbiting around objects, can someone help?

Legacy Survey Sky Browser What are these?

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Welcome! I am guessing you are referring to the very white spots. They are stars that are, relatively, fairly close to Earth. As a result, the light they emit is strong enough to oversaturate the detectors, causing these very bright spots (and occasional weird colours like greens and blues). Sometimes these over-saturation patterns can have weird and wonderful patterns on them - there is a collection of smiley-faced patterns somewhere :slight_smile:.

The lines coming from them are called diffraction spikes. These are caused by light diffracting in a telescope/detector.

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What I’m confused about in this image are the darker-looking red/orange spots on the yellow background! Cross-talk?? What else makes compact, star-shaped dark spots?
cheers,
dustin

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The lack of pattern makes me think no crosstalk (maybe too much to be crosstalk as well?). The little red dots are present all over I think and they just look more dramatic on a yellow background. Seems to be more dots in the nebula area - apparently red dots in nebulae can sometimes be protostars? I can’t see any other reason for it but I am not sure.

Just looks like stars to me, only with background here, further on there are the same stars without the yellow background

But they’re darker than the background!

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Background stars extrinsically reddened by the nebula’s dust is my guess.

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A tiny distance away, the exact same image only lacking the bright yellow background

Perhaps indeed dust reddening also plays a part

https://decaps.legacysurvey.org//viewer/?ra=259.9400&dec=-36.2094&layer=decaps2&zoom=15

My point is that background stars (even highly reddened) plus yellow foreground doesn’t make orange – it makes brighter yellow! (Light adds). That is, I don’t see how you make compact (star-like) fainter spots in an image, unless it’s something point-like that’s absorbing light.

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Are you placing the points (stars) in front or behind the yellow stuff (or inside…)?

I think switching to the riY view and seeing how they change is informative.

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Agreed - reddened stars

Any consensus on what’s what here, background / foreground, darker / lighter and if it all adds up or not?

I was going to get the info but simbad is down and there’s some wifi issues happenning right now

I think its that the background stars are behind enough extinction that they’re fainter than the nebula at earlier wavelengths, but brighter than it at the redder band(s?), so they’re only visible at certain bands, and therefore are showing up as red bright point sources.

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Foreground dust is causing the reddening of these stars.

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