APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 3582
Joined: Fri Dec 04, 2009 3:27 am

APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by APOD Robot » Tue Jan 01, 2019 5:14 am

Image The Sombrero Galaxy in Infrared

Explanation: This floating ring is the size of a galaxy. In fact, it is a galaxy -- or at least part of one: the photogenic Sombrero Galaxy, one of the largest galaxies in the nearby Virgo Cluster of Galaxies. The dark band of dust that obscures the mid-section of the Sombrero Galaxy in optical light actually glows brightly in infrared light. The featured image, digitally sharpened, shows the infrared glow, recently recorded by the orbiting Spitzer Space Telescope, superposed in false-color on an existing image taken by NASA's Hubble Space Telescope in optical light. The Sombrero Galaxy, also known as M104, spans about 50,000 light years across and lies 28 million light years away. M104 can be seen with a small telescope in the direction of the constellation Virgo.

<< Previous APOD This Day in APOD Next APOD >>

User avatar
Ann
4725 Å
Posts: 9583
Joined: Sat May 29, 2010 5:33 am

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by Ann » Tue Jan 01, 2019 8:16 am

While today's (repeat) APOD gives a fascinating 3D insight into the inner workings of the Sombrero galaxy, two other pictures may shed further enlightenment on this iconic "island universe".

The Sombrero Galaxy. R. Kennicut et al, NASA
The Sombrero Galaxy. JPL/NASA
















In the picture at left, today's APOD, we mostly see the contrast between the stars and the dust of M104. In the picture at right, we can more easily see structures in the distribution of stars. At right, the relatively bright (light blue) flat inner disk entirely made up of stars is quite obvious. It is clearly set off from the fainter, spherical halo of stars.

It has been argued that the Sombrero galaxy is two galaxies in one! And it is the red ring of dust and stars that is "the other galaxy".

(Or possibly it is the inner disk that is "the other galaxy". Don't ask me about the halo.)
Jason Major of Universe Today wrote:

Spitzer discerned that the flat disk within the galaxy is made up of two sections — an inner disk composed almost entirely of stars with no dust, and an outer ring containing both dust and stars.
...
“The Sombrero is more complex than previously thought,” said Dimitri Gadotti of the European Southern Observatory in Chile and lead author of the report. “The only way to understand all we know about this galaxy is to think of it as two galaxies, one inside the other.”
...
(I)t's thought that the Sombrero accumulated a lot of extra gas billions of years ago when the Universe was populated with large clouds of gas and dust. The extra gas fell into orbit around the galaxy, eventually spinning into a flattened disk and forming new stars.

The vigorously starforming days of M104 are long over. There exists an ultraviolet GALEX image of M104, which shows that M104 is virtually "all yellow and no blue", meaning that there are extremely few young ultraviolet-bright stars in this galaxy.


M104 GALEX.png

Ann
You do not have the required permissions to view the files attached to this post.
Color Commentator

heehaw

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by heehaw » Tue Jan 01, 2019 10:38 am

Beautiful!

BDanielMayfield
Don't bring me down
Posts: 1991
Joined: Thu Aug 02, 2012 11:24 am
AKA: Bruce
Location: East Idaho

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by BDanielMayfield » Tue Jan 01, 2019 3:21 pm

I was a bit surprised by these two statements in today's Explanation:
the photogenic Sombrero Galaxy, one of the largest galaxies in the nearby Virgo Cluster of Galaxies.
The Sombrero Galaxy, also known as M104, spans about 50,000 light years across
50,000 ly is less than half the size of our Milky Way, while our neighbor Andromeda is larger still, and yet the smallish Sombrero is 'one of the largest galaxies in Virgo' :?:

An earlier APOD's Explanation said this about the Virgo Cluster:
The Virgo Cluster of Galaxies is the closest cluster of galaxies to our Milky Way Galaxy. The Virgo Cluster is so close that it spans more than 5 degrees on the sky - about 10 times the angle made by a full Moon. It contains over 100 galaxies of many types - including spiral, elliptical, and irregular galaxies. The Virgo Cluster is so massive that it is noticeably pulling our Galaxy toward it.
More reasons for Local Group pride I guess. Our galaxies are behemoths :!:

Bruce
"Happy are the peaceable ... "

sillyworm 2

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by sillyworm 2 » Tue Jan 01, 2019 3:52 pm

It has been decided that a galaxy could not have traveled through leaving the distinct outer ring & gas? Hard to tell from the angle..are there any spiral formations at all within the inner disc? Reminds me of a pancake elliptical.

DL MARTIN

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by DL MARTIN » Tue Jan 01, 2019 3:55 pm

Shouldn't the Milky Way be tugging at Virgo?

BDanielMayfield
Don't bring me down
Posts: 1991
Joined: Thu Aug 02, 2012 11:24 am
AKA: Bruce
Location: East Idaho

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by BDanielMayfield » Tue Jan 01, 2019 4:07 pm

sillyworm 2 wrote:
Tue Jan 01, 2019 3:52 pm
It has been decided that a galaxy could not have traveled through leaving the distinct outer ring & gas?
The lack of any tidal distortion suggests not, and very strongly I would think.
Hard to tell from the angle..are there any spiral formations at all within the inner disc? Reminds me of a pancake elliptical.
No, there aren't. It's a ring and an elliptical.
"Happy are the peaceable ... "

User avatar
Ann
4725 Å
Posts: 9583
Joined: Sat May 29, 2010 5:33 am

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by Ann » Tue Jan 01, 2019 4:12 pm

BDanielMayfield wrote:
Tue Jan 01, 2019 3:21 pm
I was a bit surprised by these two statements in today's Explanation:
the photogenic Sombrero Galaxy, one of the largest galaxies in the nearby Virgo Cluster of Galaxies.
The Sombrero Galaxy, also known as M104, spans about 50,000 light years across
50,000 ly is less than half the size of our Milky Way, while our neighbor Andromeda is larger still, and yet the smallish Sombrero is 'one of the largest galaxies in Virgo' :?:

An earlier APOD's Explanation said this about the Virgo Cluster:
The Virgo Cluster of Galaxies is the closest cluster of galaxies to our Milky Way Galaxy. The Virgo Cluster is so close that it spans more than 5 degrees on the sky - about 10 times the angle made by a full Moon. It contains over 100 galaxies of many types - including spiral, elliptical, and irregular galaxies. The Virgo Cluster is so massive that it is noticeably pulling our Galaxy toward it.
More reasons for Local Group pride I guess. Our galaxies are behemoths :!:

Bruce
Well, 50,000 ly in diameter for M104 is sort of tiny. Then again, you must remember that M104 has this huge halo of stars. And the halo presumably contains a lot of dark matter, too.

I read somewhere that giant elliptical galaxy M87 is about the same size in diameter as the Milky Way. But because of the spherical shape of M87 and the fact that many of its stars are quite closely packed together, it contains way, way more mass than the Milky Way.

Ann
Color Commentator

User avatar
Ann
4725 Å
Posts: 9583
Joined: Sat May 29, 2010 5:33 am

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by Ann » Tue Jan 01, 2019 4:14 pm

BDanielMayfield wrote:
Tue Jan 01, 2019 4:07 pm
sillyworm 2 wrote:
Tue Jan 01, 2019 3:52 pm
It has been decided that a galaxy could not have traveled through leaving the distinct outer ring & gas?
The lack of any tidal distortion suggests not, and very strongly I would think.
Hard to tell from the angle..are there any spiral formations at all within the inner disc? Reminds me of a pancake elliptical.
No, there aren't. It's a ring and an elliptical.
To me it looks like a 3-component galaxy: A flat non-starforming disk, a ring of dust and stars and an elliptical-type halo.

Ann
Color Commentator

sillyworm 2

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by sillyworm 2 » Tue Jan 01, 2019 4:20 pm

An enigma for sure! A quite fascinating galaxy.Would someone please tilt so we could get a different perspective?

BDanielMayfield
Don't bring me down
Posts: 1991
Joined: Thu Aug 02, 2012 11:24 am
AKA: Bruce
Location: East Idaho

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by BDanielMayfield » Tue Jan 01, 2019 4:22 pm

DL MARTIN wrote:
Tue Jan 01, 2019 3:55 pm
Shouldn't the Milky Way be tugging at Virgo?
(1) It does. For every action ...
(2) Yeah, we're bigger. But all those little munchkin galaxies add up.
"Happy are the peaceable ... "

User avatar
neufer
Vacationer at Tralfamadore
Posts: 16026
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by neufer » Tue Jan 01, 2019 4:51 pm

BDanielMayfield wrote:
Tue Jan 01, 2019 4:22 pm
DL MARTIN wrote:
Tue Jan 01, 2019 3:55 pm

Shouldn't the Milky Way be tugging at Virgo?
(1) It does. For every action ...
(2) Yeah, we're bigger. But all those little munchkin galaxies add up.
  • They aren't all munchkin galaxies:
https://en.wikipedia.org/wiki/Messier_87 wrote:
<<Messier 87 (also known as Virgo A or NGC 44867) is a supergiant elliptical galaxy in the constellation Virgo. M87 is one of the most massive galaxies in the local Universe. It spans a diameter of 120 thousand light-years, which is slightly lower than that of the Milky Way, but M87 is a spheroid, not a flat spiral. M87 has an estimated mass to luminosity ratio of 6.3 ± 0.8; that is, about one part in six of the galaxy's mass is in the form of stars that radiate energy. The total mass of M87 may be 200 times that of the Milky Way.>>
Art Neuendorffer

BDanielMayfield
Don't bring me down
Posts: 1991
Joined: Thu Aug 02, 2012 11:24 am
AKA: Bruce
Location: East Idaho

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by BDanielMayfield » Tue Jan 01, 2019 6:28 pm

neufer wrote:
Tue Jan 01, 2019 4:51 pm
BDanielMayfield wrote:
Tue Jan 01, 2019 4:22 pm
DL MARTIN wrote:
Tue Jan 01, 2019 3:55 pm

Shouldn't the Milky Way be tugging at Virgo?
(1) It does. For every action ...
(2) Yeah, we're bigger. But all those little munchkin galaxies add up.
  • They aren't all munchkin galaxies:
https://en.wikipedia.org/wiki/Messier_87 wrote:
<<Messier 87 (also known as Virgo A or NGC 44867) is a supergiant elliptical galaxy in the constellation Virgo. M87 is one of the most massive galaxies in the local Universe. It spans a diameter of 120 thousand light-years, which is slightly lower than that of the Milky Way, but M87 is a spheroid, not a flat spiral. M87 has an estimated mass to luminosity ratio of 6.3 ± 0.8; that is, about one part in six of the galaxy's mass is in the form of stars that radiate energy. The total mass of M87 may be 200 times that of the Milky Way.>>
Nice to know Art. Thanks
"Happy are the peaceable ... "

BDanielMayfield
Don't bring me down
Posts: 1991
Joined: Thu Aug 02, 2012 11:24 am
AKA: Bruce
Location: East Idaho

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by BDanielMayfield » Tue Jan 01, 2019 6:46 pm

So, the Local group is being pulled toward the Virgo Cluster, and yet I read this about M104 aka The Sombrero:
This galaxy was the first one with a large redshift found, by Vesto M. Slipher at Lowell Observatory in 1912. Its redshift corresponds to a recession velocity of about 1,000 km/sec (it is caused by the Hubble effect, i.e. the cosmic expansion).
If we're being pulled toward Virgo, how could a member of Virgo have such a large recessional redshift?
"Happy are the peaceable ... "

User avatar
neufer
Vacationer at Tralfamadore
Posts: 16026
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by neufer » Tue Jan 01, 2019 10:35 pm

BDanielMayfield wrote:
Tue Jan 01, 2019 6:46 pm

So, the Local group is being pulled toward the Virgo Cluster, and yet I read this about M104 aka The Sombrero:
This galaxy was the first one with a large redshift found, by Vesto M. Slipher at Lowell Observatory in 1912. Its redshift corresponds to a recession velocity of about 1,000 km/sec (it is caused by the Hubble effect, i.e. the cosmic expansion).
If we're being pulled toward Virgo, how could a member of Virgo have such a large recessional redshift?
Because the Virgocentric flow (VCF) of Local Group galaxies towards the Virgo cluster amounts to only about 100 to 400 km/s.

[Also, 120 km/s of the observed recession velocity of the Sombrero Galaxy is due to the Earth's rotation around the Milky Way.]
https://en.wikipedia.org/wiki/Virgocentric_flow wrote:
<<The Virgocentric flow (VCF) is the preferred movement of Local Group galaxies towards the Virgo cluster caused by its overwhelming gravity, which separates bound objects from the Hubble flow of cosmic expansion. The VCF can refer to the Local Group's movement towards the Virgo Supercluster, since its center is considered synonymous with the Virgo cluster, but more tedious to ascertain due to its much larger volume. The excess velocity of Local Group galaxies towards, and with respect to, the Virgo Cluster are 100 to 400 km/s. This excess velocity is referred to as each galaxy's peculiar velocity.>>
Art Neuendorffer

hypersonic
Asternaut
Posts: 1
Joined: Sun Feb 13, 2011 1:41 pm

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by hypersonic » Wed Jan 02, 2019 1:47 pm

Errr,
Great daily entry as ever, but is this not in fact a copy of THIS entry from 4th October 2014?
https://apod.nasa.gov/apod/ap151004.html

Even the wording seems identical?
Just asking......

User avatar
neufer
Vacationer at Tralfamadore
Posts: 16026
Joined: Mon Jan 21, 2008 1:57 pm
Location: Alexandria, Virginia

Re: APOD: The Sombrero Galaxy in Infrared (2019 Jan 01)

Post by neufer » Wed Jan 02, 2019 2:15 pm

Click to play embedded YouTube video.
hypersonic wrote:
Wed Jan 02, 2019 1:47 pm

Errr, Great daily entry as ever, but is this not in fact a copy of THIS entry from 4th October 2014?
https://apod.nasa.gov/apod/ap151004.html

Even the wording seems identical?
Just asking......
It's a Federally holiday ... plus: NASA is part of the Trump shutdown.

What did you expect?
Art Neuendorffer