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M104: The Sombrero Galaxy

Explanation: The striking spiral galaxy M104 is famous for its nearly edge-on profile featuring a broad ring of obscuring dust lanes. Seen in silhouette against an extensive bulge of stars, the swath of cosmic dust lends a broad brimmed hat-like appearance to the galaxy suggesting the more popular moniker, The Sombrero Galaxy. Hubble Space Telescope and ground-based Subaru data have been reprocessed with amateur color image data to create this sharp view of the well-known galaxy. The processing results in a natural color appearance and preserves details often lost in overwhelming glare of M104's bright central bulge when viewed with smaller ground-based instruments. Also known as NGC 4594, the Sombrero galaxy can be seen across the spectrum and is thought to host a central supermassive black hole. About 50,000 light-years across and 28 million light-years away, M104 is one of the largest galaxies at the southern edge of the Virgo Galaxy Cluster.

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APOD Robot wrote:The processing results in a natural color appearance and preserves details often lost in overwhelming glare of M104's bright central bulge when viewed with smaller ground-based instruments.

That comment doesn't make sense to me. The dynamic range isn't a function of the size of the telescope. The HST has higher resolution, of course. The Subaru and amateur instrument have similar resolution for wide fields. I understand how using luminance data from the larger scopes can be combined with amateur color data to get more natural colors while preserving the higher resolution. But that's all.

It's like you guys have run out of things to show us. Is this all there is? Why are there hardly any NEW images on APOD? I've been following this site since it began, and have seen a bunch of cool pics, but I also have noticed, the same images over and over. Are there no NEW images? Has Hubble stopped working since APOD started? What gives???
It's like you have so many, then, just repeat them... Why are you not showing new images? New galaxies? You can't tell me there aren't any left to show.

Joe Nobody wrote:It's like you guys have run out of things to show us. Is this all there is? Why are there hardly any NEW images on APOD? I've been following this site since it began, and have seen a bunch of cool pics, but I also have noticed, the same images over and over. Are there no NEW images? Has Hubble stopped working since APOD started? What gives???
It's like you have so many, then, just repeat them... Why are you not showing new images? New galaxies? You can't tell me there aren't any left to show.

If you think that there are no new images, you haven't been paying very much attention. Today's is a new image of the Sombrero Galaxy. Yesterday? New image of sprites. Before that? Brand new image of 67p. And before that? Brand new, never before featured composite of Titan. It practically can't get any newer. Reruns are primarily on weekends to give the editors a break (there are only two of them doing the whole thing).

fantastic image !
Did you put attention that Sombrero is a perfect lenticular galaxy, which ended its active life !
and where this enormous quantity of dust come for?
And the central question: how this beautiful halo of stars appears?

Isn't this galaxy supposed to have a really high number of globular clusters?

If M104 is only 28 million light years away, how can it be part of the Virgo Cluster?

Joe Nobody wrote:It's like you guys have run out of things to show us. Is this all there is? Why are there hardly any NEW images on APOD?

Hey, at least we get to comment! Unlike on http://epod.usra.edu/blog/ ! ....where they do re-runs as well! I'm a professional astronomer, and I LOVE APOD!

Sombrero!?! It looks much more like a flying saucer to me.

Below the Sombrero galaxy is a group of stars that look sort of like a lensing (see green circle, or if image too small, look closely at image).
The stars' images aren't mirrored. Is this a photoshot goof, a coincidence, or something else?
http ://i.imgur.com/zwZDGOq.jpg

Hi!
Yes it is for sure a mistake I did in the assembling, not at all a coincidence.

Bests

The last statement implies that M104 is a member of the Virgo Cluster. But at the link it is clearly stated that it is a foreground galaxy, 2/3 of the way between us and Virgo.

Here's a chicken or the egg scenario-

Is it known which came first; the black hole or the galaxy? Being centrally located one might think it was there first, afterwards attracting the matter which surrounds. But then again perhaps it formed from as a result of the abundance of matter; collapsing to form a black hole which grew larger?

My first inclination was the latter. Then again, they might be: the former of galaxies. Do we know for sure?

Ron-Astro Pharmacist wrote:Is it known which came first; the black hole or the galaxy?

Unknown. There are models for both scenarios. Evidence leans towards the black holes forming very early in the life of the galaxy, however, and not being the seed of galaxy formation.

geckzilla wrote:

Joe Nobody wrote:It's like you guys have run out of things to show us. Is this all there is? Why are there hardly any NEW images on APOD? I've been following this site since it began, and have seen a bunch of cool pics, but I also have noticed, the same images over and over. Are there no NEW images? Has Hubble stopped working since APOD started? What gives???
It's like you have so many, then, just repeat them... Why are you not showing new images? New galaxies? You can't tell me there aren't any left to show.

If you think that there are no new images, you haven't been paying very much attention. Today's is a new image of the Sombrero Galaxy. Yesterday? New image of sprites. Before that? Brand new image of 67p. And before that? Brand new, never before featured composite of Titan. It practically can't get any newer. Reruns are primarily on weekends to give the editors a break (there are only two of them doing the whole thing).

It really only appears to be old images. As Geck stated, these are new Images but of the same things. M104 has been imaged countless times but each unique image is of the same thing giving the appearance of being the same image.
Since Nov 1995 a search for M104 gets 19 hits on the APDO search and although some are Sunday repeats many are new though ALL are M104.
I am certain that when CERES is fully resolved there will be a series of APODs containing images and similar for Pluto.
Repeats will forever happen on Sundays because Sunday is for them. Many astronomical images will appear to be repeats even if they are new simply because the object has been images before.

Chris Peterson wrote:

Ron-Astro Pharmacist wrote:Is it known which came first; the black hole or the galaxy?

Unknown. There are models for both scenarios. Evidence leans towards the black holes forming very early in the life of the galaxy, however, and not being the seed of galaxy formation.

What about central BHs and their surrounding galaxies growing together over time?

A thought occurred to me (I'm sure that others must have thought of this too): The most efficient way for a BH to grow is by merger with other BHs.

BDanielMayfield wrote:

Chris Peterson wrote:Unknown. There are models for both scenarios. Evidence leans towards the black holes forming very early in the life of the galaxy, however, and not being the seed of galaxy formation.

What about central BHs and their surrounding galaxies growing together over time?

A thought occurred to me (I'm sure that others must have thought of this too): The most efficient way for a BH to grow is by merger with other BHs.

Yes. Mergers are definitely one of the preferred explanations for the growth of SMBs.

The biggest theoretical problems are at the earlier stages. The energy released when black holes feed tends to push material away, which stops the feeding. It's not obvious how you get over that bump. Mergers are one solution. But it's interesting that we don't find a continuum of black holes massing from stellar to SMBs.

Joe Nobody wrote:It's like you guys have run out of things to show us. Is this all there is? Why are there hardly any NEW images on APOD? I've been following this site since it began, and have seen a bunch of cool pics, but I also have noticed, the same images over and over. Are there no NEW images? Has Hubble stopped working since APOD started? What gives???
It's like you have so many, then, just repeat them... Why are you not showing new images? New galaxies? You can't tell me there aren't any left to show.

Come on, Joe. Though your experience may be extensive, what about young ones, both in age and experience, that may be seeing this for the first time?

Also, do you get tired of your favorite foods? Do you completely appreciate all the nuances in the first experience? There is so much more to many of the APOD images we see. You yourself learn more with each day, which then helps you to see each image from a fresh perspective. Seeing other people's perspectives in the comments for that day also brings uniqueness (Ann, Geck, B Daniel Mayfield, Neufer, Chris Peterson to name a few), and with the occasional exception of disgruntled viewers or the occasional snooty remark by the Abominable Snowman (which also make me smile, I must admit), every day is a fresh day.

APOD staff and posters: thank you for all the hard work! Even "repeats" are appreciated.

-Gabe

starsurfer wrote:Isn't this galaxy supposed to have a really high number of globular clusters?

Yeah. You can see a lot of them in the image, but most people would guess that those small dots are foreground stars.

Did anyone notice or appreciate that this image of M104 is obviously from the other side of the galaxy
Or is it that the image was just mirrored from the regular orientation

There are some "filaments" in the image that look like what you would see if you scanned a picture that has a lot of dust on it. Above the Galactic disk, over tot he right 1/2 galactic radius and up one radius. They look like little filaments. I'm sure these are artifacts of some sort, but they are also all different, so it not a "camera shake" type thing.

Love the images, thanks for doing this!

Can anyone identify what appears to be a pair of interacting galaxies just below and to the right (see arrow in this picture)?
http://i.imgur.com/BAhnRIO.png

does the direction of the spin axis of these things remain forever, since birth ?

foresthillsbob wrote:Can anyone identify what appears to be a pair of interacting galaxies just below and to the right (see arrow in this picture)?
http://i.imgur.com/BAhnRIO.png

2MASX J12400754-1140015
CXOU J124007.15-114001.8

Not much to go on. They aren't studied beyond noting that one exists and the other has an x-ray source within it. Most of these small/distant galaxies are anonymous.

ta152h0 wrote:does the direction of the spin axis of these things remain forever, since birth ?

You have to consider what the spin axis even is for a non-rigid body like a galaxy. Some galaxies have no common spin axis at all- their constituent stars orbit in random inclinations (as with a globular cluster). Some have weak commonality (as with many ellipticals). Some have an apparent planar structure, although the majority of the mass in the central bulge still shares no common inclination.

That said, I'd expect the disc plane of an isolated spiral to remain pretty constant. But if it were to interact with another galaxy- even without an actual collision- the plane could be significantly altered.