Whirlpool object - comet?

https://www.legacysurvey.org//viewer/?ra=153.7944&dec=-1.6833&layer=hsc-dr3&zoom=14

This must be a comet if I’m understanding the data right that it is very close. It looks like it is headed straight at us or away, because of the nice whirlpool effect.

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Nope just a galaxy sadly. I believe Tom has already posted on one of your posts that is an asteroid. There does seem to be some sort of material in concentric rings around it. This is most likely material that has been thrown around post merger or pulled outwards tidally in an interaction.

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This is an unusual example of a Shell Galaxy

Shell galaxies happen when a pair of galaxies are attracted directly toward each other (or as in this case, very nearly so)

Cores are very dense, VERY massive objects but there is still plenty of room between stars for two cores to pass through each other.

All that mass created very strong attraction which increased rapidly as they neared, creating tremendous momentum.

The large momentum kept them moving forward until it was overcome by gravitational attraction again.

Rinse & repeat with ever smaller momentums until the two nuclei merge or, as we see here, they shift to a crazy death spiral.

The point is that at every vector change the galaxies leave inertial, or centrifugal, imprints of stars left behind - thus the shells.

See Two merging galaxies are simulated as an n-body system with a total of 150,000 particles

Also, see NGC 3923
https://www.legacysurvey.org//viewer/?ra=177.7491&dec=-28.7984&layer=ls-dr10&zoom=11

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Thank you for the word, slipped my mind.

I’ve never heard of shell galaxies before. Thanks for the explanation!

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