Galaxy Zoo Talk

Extended spiral arms/tidal streams visible in the DECaLS Skyserver

  • Ghost_Sheep_SWR by Ghost_Sheep_SWR

    Really nice find! (OP by Abe_Hoekstra)

    Looks like faint interaction over a great great distance from NGC 3580 (z=0.023) with smaller galaxy (z=0.022).

    enter image description here

    http://legacysurvey.org/viewer?ra=168.3269&dec=3.6299&zoom=13&layer=decals-dr2

    Posted

  • Abe_Hoekstra by Abe_Hoekstra

    Thanks for posting the DECaLS image Ghost_Sheep_SWR 😃! I deleted my find because I didn't want to share this one yet. Anyway here is the SDSS image again:

    enter image description here

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  • Abe_Hoekstra by Abe_Hoekstra

    Also thank you to Dolorous_Edd. I contacted him and he calculated this galaxy was about 78.000 parsecs across, which would make this 254.000 lightyears across, bigger than the Andromeda galaxy but smaller than the Tadpole galaxy. I was surprised to find the very faint arms, which are huge imho.

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  • Ghost_Sheep_SWR by Ghost_Sheep_SWR

    No problem, it's easy just click anywhere in DECaLS, select 'cutout' and voila!

    Thread looks weird now, i can delete my post if you want to.

    Looks like interaction IMHO, which is incredible in itself. If it isn't that would be even more amazing!

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  • Abe_Hoekstra by Abe_Hoekstra

    You don't have to delete, I appreciate the input and advice 😃.

    NGC 3580 doesn't look disturbed at all, and neither does the nucleus of our galaxy. Still you would think this is the result of interaction between the two. It is an interesting galaxy. And the arms/streams, it looks like they are composed of gas, I don't see any starformation.

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  • Abe_Hoekstra by Abe_Hoekstra

    Getting the hang of it 😃

    enter image description here

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  • Abe_Hoekstra by Abe_Hoekstra

    By the way I have already contacted a few astronomers who might be interested in this galaxy. I am not leaving anything to chance here. If you know what I mean.

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  • Ghost_Sheep_SWR by Ghost_Sheep_SWR in response to Abe_Hoekstra's comment.

    For control of the image size, in the box where you paste the URL of the image, type =350x directly behind the pasted text. Or any other value not too big, there is a maximum I think.

    How do you know which scientists to contact, or do you know them personally?

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  • Abe_Hoekstra by Abe_Hoekstra

    OK, thanks again 😃.

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  • Abe_Hoekstra by Abe_Hoekstra

    The inverted SDSS image:

    enter image description here

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  • Abe_Hoekstra by Abe_Hoekstra

    So a few questions remain:

    1. Why do NGC 3580 and the part of the galaxy that can be seen in the visible part of the spectrum appear mainly undisturbed?

    2. What are the arms made out of? As they are mostly visible in the DECaLS Skyserver images I would suspect they consist mainly of gas.

    3. Why two arms in opposite directions? You would think there would be only one pointing in the direction of NGC 3580. But there are two, one pointing away from NGC 3580. Is the southern arm the result of a previous meeting with NGC 3580?

    4. Does the northern stream belong to our galaxy or NGC 3580?

    5. Is there still interaction going on between the two galaxies? I would say, yes.

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  • Abe_Hoekstra by Abe_Hoekstra

    Ghost_Sheep_SWR - wrt to your question: DECaLS has its own discussion page, and I posted this galaxy on their page.

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  • Ghost_Sheep_SWR by Ghost_Sheep_SWR

    Ah yes i am aware of that function, never posted there really, might be good practice.

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