APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

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Expand view Topic review: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by neufer » Sat Feb 22, 2020 3:50 pm

Click to play embedded YouTube video.
alter-ego wrote: Sat Feb 22, 2020 5:50 am
There are many catalogs that list this galaxy. Funny Simbad doesn't. Of the 20 catalogs I found identifying that galaxy, I've listed several of the maybe more familiar ones and the galaxy ID. The IDs that start with a "J" are the J2000 RADec coordinates.

USNO-A2.0 (1998) → 1125-19802822
USNO-B1.0 (2003) → 1185-0599561
NOMAD1 (2005) → 1185-0625599
2MASS Extended Sources (2003 -2006) → 23252974+2830217
ALLWISE (2013) → J232529.77+283021.3
SDSS DR12 (2015) → J232529.77+283021.0
Pan-STARRS DR1 (2016) → 142203513740877647

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Chris Peterson » Sat Feb 22, 2020 1:31 pm

alter-ego wrote: Sat Feb 22, 2020 5:50 am
hypatia wrote: Fri Feb 21, 2020 9:07 pm
Chris Peterson wrote: Thu Feb 20, 2020 10:13 pm

Based on a SIMBAD query, it appears to be uncataloged.

Thanks.
There are many catalogs that list this galaxy. Funny Simbad doesn't. Of the 20 catalogs I found identifying that galaxy, I've listed several of the maybe more familiar ones and the galaxy ID. The IDs that start with a "J" are the J2000 RADec coordinates.
USNO-A2.0 (1998) → 1125-19802822
USNO-B1.0 (2003) → 1185-0599561
NOMAD1 (2005) → 1185-0625599
2MASS Extended Sources (2003 -2006) → 23252974+2830217
ALLWISE (2013) → J232529.77+283021.3
SDSS DR12 (2015) → J232529.77+283021.0
Pan-STARRS DR1 (2016) → 142203513740877647
Yeah, I didn't do any deep search. SIMBAD is pretty reliable when it comes to consolidating catalogs. I was surprised that such an apparently prominent object wasn't there, but didn't look farther.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Ann » Sat Feb 22, 2020 6:05 am

alter-ego wrote: Sat Feb 22, 2020 5:50 am
hypatia wrote: Fri Feb 21, 2020 9:07 pm
Chris Peterson wrote: Thu Feb 20, 2020 10:13 pm

Based on a SIMBAD query, it appears to be uncataloged.

Thanks.
There are many catalogs that list this galaxy. Funny Simbad doesn't. Of the 20 catalogs I found identifying that galaxy, I've listed several of the maybe more familiar ones and the galaxy ID. The IDs that start with a "J" are the J2000 RADec coordinates.
USNO-A2.0 (1998) → 1125-19802822
USNO-B1.0 (2003) → 1185-0599561
NOMAD1 (2005) → 1185-0625599
2MASS Extended Sources (2003 -2006) → 23252974+2830217
ALLWISE (2013) → J232529.77+283021.3
SDSS DR12 (2015) → J232529.77+283021.0
Pan-STARRS DR1 (2016) → 142203513740877647
Thanks, alter-ego, I'm impressed!

Ann

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by alter-ego » Sat Feb 22, 2020 5:50 am

hypatia wrote: Fri Feb 21, 2020 9:07 pm
Chris Peterson wrote: Thu Feb 20, 2020 10:13 pm
hypatia wrote: Thu Feb 20, 2020 9:58 pm

I figured that BUT which galaxy is it?
Based on a SIMBAD query, it appears to be uncataloged.

Thanks.
There are many catalogs that list this galaxy. Funny Simbad doesn't. Of the 20 catalogs I found identifying that galaxy, I've listed several of the maybe more familiar ones and the galaxy ID. The IDs that start with a "J" are the J2000 RADec coordinates.
USNO-A2.0 (1998) → 1125-19802822
USNO-B1.0 (2003) → 1185-0599561
NOMAD1 (2005) → 1185-0625599
2MASS Extended Sources (2003 -2006) → 23252974+2830217
ALLWISE (2013) → J232529.77+283021.3
SDSS DR12 (2015) → J232529.77+283021.0
Pan-STARRS DR1 (2016) → 142203513740877647

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by hypatia » Fri Feb 21, 2020 9:07 pm

Chris Peterson wrote: Thu Feb 20, 2020 10:13 pm
hypatia wrote: Thu Feb 20, 2020 9:58 pm
Chris Peterson wrote: Thu Feb 20, 2020 12:18 am

Another galaxy.
I figured that BUT which galaxy is it?
Based on a SIMBAD query, it appears to be uncataloged.

Thanks.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Chris Peterson » Thu Feb 20, 2020 10:13 pm

hypatia wrote: Thu Feb 20, 2020 9:58 pm
Chris Peterson wrote: Thu Feb 20, 2020 12:18 am
hypatia wrote: Thu Feb 20, 2020 12:01 am What is the 'object' in the upper right?
Another galaxy.
I figured that BUT which galaxy is it?
Based on a SIMBAD query, it appears to be uncataloged.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by hypatia » Thu Feb 20, 2020 9:58 pm

Chris Peterson wrote: Thu Feb 20, 2020 12:18 am
hypatia wrote: Thu Feb 20, 2020 12:01 am What is the 'object' in the upper right?
Another galaxy.
I figured that BUT which galaxy is it?

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by sillyworm 2 » Thu Feb 20, 2020 12:50 pm

I'm going to search for the name/ designation of the large upper right galaxy.If anyone knows already please chime in.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Ann » Thu Feb 20, 2020 3:55 am

MarkBour wrote: Wed Feb 19, 2020 6:11 pm
spinlock wrote: Wed Feb 19, 2020 4:57 pm ... I was trying to make a clearer view of faint galaxies in the background as well as making the dust lanes more visible ...
Leo Shatz
You succeeded beautifully, I think. I greatly enjoyed looking around at that menagerie of surrounding galaxies.
I agree. I should have mentioned in my original comment that the background galaxies do indeed look sharper and more interesting in your image than in the original Space Telescope one.

Ann

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Chris Peterson » Thu Feb 20, 2020 12:18 am

hypatia wrote: Thu Feb 20, 2020 12:01 am What is the 'object' in the upper right?
Another galaxy.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by hypatia » Thu Feb 20, 2020 12:01 am

What is the 'object' in the upper right?

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by neufer » Wed Feb 19, 2020 7:47 pm

jeffplay wrote: Wed Feb 19, 2020 7:37 pm
What happened to the theory that dark matter held together a fast spinning galaxy?
https://en.wikipedia.org/wiki/Milky_Way wrote:
<<Stars and gases at a wide range of distances from the Milky Way's Galactic Center orbit at approximately 220 kilometers per second. The constant rotation speed contradicts the laws of Keplerian dynamics and suggests that much (about 90%) of the (0.8–1.5×1012 M) mass of the Milky Way is invisible to telescopes, neither emitting nor absorbing electromagnetic radiation. This conjectural mass has been termed "dark matter". The rotational period is about 240 million years at the radius of the Sun.>>
Gravitational Force: M/R2 = V2/R : Centrifugal "Force"

M/R = V2

For UGC 12591 to have twice the Milky Way's orbital speeds it must either be:
  • 1) 4 times as massive or
    2) 4 times as compact.
or some combination of the two.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by jeffplay » Wed Feb 19, 2020 7:37 pm

What happened to the theory that dark matter held together a fast spinning galaxy?

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Chris Peterson » Wed Feb 19, 2020 6:34 pm

spinlock wrote: Wed Feb 19, 2020 4:57 pm I acknowledge the sin of having too much of the blue color in galaxies halos, as I also thought it could be wrong in attempt to simulate "natural colors" from bi-color data. I was trying to make a clearer view of faint galaxies in the background as well as making the dust lanes more visible, while reducing the green cast of the original image. It's interesting to know that raw linear image has quite bright halo at the center of UGC 12591, which essentially hides all details of the core and some of the the galaxy's ring structure at its distant side. The APOD image brings out these details at the expense of making that central halo much dimmer
It is wise to not worry about any color absolutes when you're working with data that can't provide that. Much better to focus on the particular details you want to bring out, and base your color decisions on that... not on any vague sense of "natural".

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by MarkBour » Wed Feb 19, 2020 6:11 pm

spinlock wrote: Wed Feb 19, 2020 4:57 pm ... I was trying to make a clearer view of faint galaxies in the background as well as making the dust lanes more visible ...
Leo Shatz
You succeeded beautifully, I think. I greatly enjoyed looking around at that menagerie of surrounding galaxies.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by MarkBour » Wed Feb 19, 2020 6:07 pm

apodJona wrote: Wed Feb 19, 2020 8:34 am How can a rotation be stated as [km/s]?
Wouldn't [rad/s] be more logical?
So, here's the thing about the rotations of disk galaxies.
  • Our first expectation was Keplerian rotational motions, so that the farther a star is from the center of the galaxy, the slower its rotation in terms of km/s and even more pronounced -- an inverse square relation -- its slowing if measured in rad/s.
  • It was surprising, though, when rotational motions were measured. You might think that what was surprising was that the whole thing rotated as a solid object, so that everything in the disk rotated much more rapidly in km/s as you went out, all maintaining a roughly constant rad/s (and km/s would go up linearly with radius).
    Capture1.jpg
  • Actually, the observations are in between these two. Although the stars do not rotate with a consistent rad/s, as one goes from the center to the edge, the km/s measurements are surprisingly consistent.
    Wikipedia: Galaxy rotation curve
    Stars revolve around their galaxy's centre at equal or increasing speed over a large range of distances.
    The curves would be more informative, as @isoparix said, but as a first measure, for many galaxies, an approximate single value of km/s does give an overall characterization that is quite meaningful. Without having the actual rotational curve for UGC 12591, I suspect it looks like the image above, but with the high point on the y-axis labelled at 500 km/s instead of 200 km/s.
And that extreme value of 500 km/s is UGC 12591's claim to fame.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Psnarf » Wed Feb 19, 2020 6:02 pm

The dust lanes appear circular, not spiral, like a pebble dropped into calm waters. Gravity waves from the super-massive black hole? I don't believe in dark matter, methinks the gravitational effects of the black hole are severely underestimated, but then, my feeble understanding of such matters dismisses my blathering twaddle.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by spinlock » Wed Feb 19, 2020 4:57 pm

Ann wrote: Wed Feb 19, 2020 7:29 am It is interesting to compare today's APOD with the original image of this galaxy, published on Space Telescope's own website.

As you can see, the color balance of the APOD is much bluer, so blue that the lenticular, "red and dead" barred galaxy at upper right looks blue, even though it totally lacks any sign of star formation. The likely reason for the blue color balance of the APOD is that the original image is a two-filter image, where the filters are 606 nm (centered on orange) and 814 nm (near infrared). Presumably the 606 nm filter image has been treated as blue in the APOD, or at least a bright shade of cyan. In my opinion, there is very little "true cyan" in UGC 12591 or in any of its neighboring galaxies, which is to say that the original Space Telescope image looks much more "natural" to me.

The details in the dust lane of UGC 12591 have also been sharpened in the APOD.

...
Ann
I acknowledge the sin of having too much of the blue color in galaxies halos, as I also thought it could be wrong in attempt to simulate "natural colors" from bi-color data. I was trying to make a clearer view of faint galaxies in the background as well as making the dust lanes more visible, while reducing the green cast of the original image. It's interesting to know that raw linear image has quite bright halo at the center of UGC 12591, which essentially hides all details of the core and some of the the galaxy's ring structure at its distant side. The APOD image brings out these details at the expense of making that central halo much dimmer.

BTW, I couldn't find catalog name of the galaxy at upper right corner, and therefore no description of it.

Leo Shatz

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by sillyworm 2 » Wed Feb 19, 2020 2:22 pm

OK. There ARE Trillions of galaxies.Mind boggling.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by sillyworm 2 » Wed Feb 19, 2020 1:54 pm

I'm rather fond of the starfish looking galaxy above the prominent galaxy.Odd how one of it's arms looks distorted/aligned differently.So many galaxies! I was just wondering why there is not an even larger density of galaxies in the Universe.(Trillions instead of Billions)

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by neufer » Wed Feb 19, 2020 1:28 pm


isoparix wrote: Wed Feb 19, 2020 12:57 pm
If the claim is made that it's 'the fastest rotating', then the claim needs to be supported by data in rotational units.

These can be rad/S, or km/S at a given radius, but km/S on its own is meaningless.
It's just that spinning/rotating 'rigid body terminology' is awkward when discussing a galaxy.

Perhaps: UGC 12591: The Fastest Known Orbital Velocities would have been preferable.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by isoparix » Wed Feb 19, 2020 12:57 pm

If the claim is made that it's 'the 'fastest rotating', then the claim needs to be supported by data in rotational units. These can be rad/S, or km/S at a given radius, but km/S on its own is meanngless. But even a correclly chosen rotation unit needs to have the particular smeasurement radius defined, because it seems dynamically impossible that the entire galaxy is rotating as one soiid disk. Rotation rate curves from spectral Doppler shifts across the glaxy would make this a much more informative claim....

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by orin stepanek » Wed Feb 19, 2020 12:02 pm

👀 I guess I never paid any attention to how fast a galaxy spins before; or if any spin faster than others! 8-)

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by heehaw » Wed Feb 19, 2020 10:14 am

If I recall arightly, Earth takes about 250 million years to go around the center of our galaxy.

Re: APOD: UGC 12591: The Fastest Rotating... (2020 Feb 19)

by Marco (Milano, Italia) » Wed Feb 19, 2020 9:59 am

After stating that rotations cannot be given in linear speed units (without specifying radius), I suppose that our commonly experienced on Earth rotation rates (360° in seconds or fractions of second, in 24 hours, in 28 days, in 365 days) cannot help. A galaxy probably takes million years to make a full turn (can anybody be more more precise ? ) that's making the radiant/s unit a completely out of scale choice.
Nonetheless that's the beauty of the Universe.
Happy every day in starting my activities with APOD !

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