APOD: Spiral Galaxy M74: A Sharper View (2022 Jul 22)

[APOD Robot]

Spiral Galaxy M74: A Sharper View

Explanation: Beautiful spiral galaxy Messier 74 (also known as NGC 628) lies some 32 million light-years away toward the constellation Pisces. An island universe of about 100 billion stars with two prominent spiral arms, M74 has long been admired by astronomers as a perfect example of a grand-design spiral galaxy. M74's central region is brought into a stunning, sharp focus in this recently processed image using publicly available data from the James Webb Space Telescope. The colorized combination of image data sets is from two of Webb's instruments NIRcam and MIRI, operating at near- and mid-infrared wavelengths. It reveals cooler stars and dusty structures in the grand-design spiral galaxy only hinted at in previous space-based views.

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[Ann]

M74 is regarded as the perfect spiral galaxy. Not only that, but it is regarded as the quintessential spiral galaxy without a bar.

M74 in visible and very near infrared light. Credits: NASA, ESA and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration; Acknowledgment: R. Chandar (University of Toledo) and J. Miller (University of Michigan)

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JWST_NGC628_Robert_Eder_V2600h[1].jpg

M74 by NIRcam and MIRI. Image Credit:
NASA, ESA, CSA, STScI; Processing Copyright: Robert Eder

But JWST has revealed that M74 has an incipient bar structure with bar-end enhancements. Bar-end enhancements are regions at the ends of the bar where gas and dust gathers in large quantities, and where barred galaxies display enhanced star formation.

APOD 22 July 2022 M74 NIRcam MIRI Robert Eder annotated.png

Barred galaxy NGC 1300. Image: NASA/ESA/Hubble Team/Kevin M. Gill

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So, who knows? M74 may just be on its way to slowly transforming into another version of NGC 1300! Well, not quite, because NGC 1300 really has an extremely prominent bar, and few galaxies can compete with it.

Ann

[bystander]

M74 Like You’ve Never Seen it Before
Universe Today | 2022 Jul 21

The JWST recently imaged NGC628, also knows an M74. Well-known astronomy image processor Judy Schmidt reworked the image to show more detail. Image Credit: NASA/ESA/CSA/STSCI/Judy Schmidt CC BY 2.0

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The JWST is grabbing headlines and eyeballs as its mission gains momentum. The telescope recently imaged M74 (NGC 628) with its Mid-Infrared Instrument (MIRI). Judy Schmidt, a well-known amateur astronomy image processor, has worked on the image to bring out more detail.

M74 is a large spiral galaxy that holds somewhere in the neighbourhood of 100 billion stars. It’s about 32 million light-years away from us and is a great example of a Grand Design Spiral Galaxy. The JWST imaged the galaxy as part of the PHANGS Survey. PHANGS (Physics at High Angular resolution in Nearby GalaxieS) studies nearby galaxies in high resolution and is intended to “… understand the interplay of the small-scale physics of gas and star formation with galactic structure and galaxy evolution,” according to the PHANGS website.

The survey uses several telescopes to study galaxies, but now that the JWST is operating, it’s making a huge contribution to the effort. ...

[AVAO]

Is there an explanation for the formation of this mesh-like structure, which becomes visible in the IR?


https://live.staticflickr.com/65535/522 ... 8e10_k.jpg
jac berne (flickr) Original data: core: NASA, ESA, CSA, STScI (JWST) arms: NASA, ESA (SST:IRAC)

[Ann]

M74 Like You’ve Never Seen it Before
Universe Today | 2022 Jul 21

The JWST recently imaged NGC628, also knows an M74. Well-known astronomy image processor Judy Schmidt reworked the image to show more detail. Image Credit: NASA/ESA/CSA/STSCI/Judy Schmidt CC BY 2.0

---

The JWST is grabbing headlines and eyeballs as its mission gains momentum. The telescope recently imaged M74 (NGC 628) with its Mid-Infrared Instrument (MIRI). Judy Schmidt, a well-known amateur astronomy image processor, has worked on the image to bring out more detail.

M74 is a large spiral galaxy that holds somewhere in the neighbourhood of 100 billion stars. It’s about 32 million light-years away from us and is a great example of a Grand Design Spiral Galaxy. The JWST imaged the galaxy as part of the PHANGS Survey. PHANGS (Physics at High Angular resolution in Nearby GalaxieS) studies nearby galaxies in high resolution and is intended to “… understand the interplay of the small-scale physics of gas and star formation with galactic structure and galaxy evolution,” according to the PHANGS website.

The survey uses several telescopes to study galaxies, but now that the JWST is operating, it’s making a huge contribution to the effort. ...

I love Geck's (and MIRI's) image!

Ann

[VictorBorun]

little transparent bar and small central BH (10 000 suns), can it be correlated?

[Isotropic Metric]

Look at this JWST image! A lens in a lens in a lens!
https://www.flickr.com/photos/nasawebbt ... 060832052/
The inset image is lensed by a giant elliptical. The big galaxy in the middle of that inset lenses a galaxy above it, which in turn has an Einstein ring around it. ...And that image of the inset looks a lot like another image below a yellow galaxy in the original image, so there may be a fourth level of lensing. How far back are we looking in the Einstein ring?

[orin stepanek]

sig06-018c.jpg

The perfect spiral!

[daddyo]

Is there an explanation for the formation of this mesh-like structure, which becomes visible in the IR?

Maybe since you now get to see to the inner cores of dense material, your looking at the condensed bars that are driving the formation of all visible material in the galaxy?

[AVAO]

Is there an explanation for the formation of this mesh-like structure, which becomes visible in the IR?

Maybe since you now get to see to the inner cores of dense material, your looking at the condensed bars that are driving the formation of all visible material in the galaxy?

ThanX for your explanations. Unfortunately, I don't really understand the concept you describe.

I know the density wave model ( https://www.youtube.com/watch?v=c5Us-jonCLA&t=5s ), but I'm not really convinced by this one considering the detailed and complex structures see that WEBB reveals to us. Magnetic forces can create complex structures, but there is still a lot of research to be done. https://www.universetoday.com/144342/ho ... ir-shape/

[VictorBorun]

Robert Eder writes:

NIRCam
F200W - yellow
F300M - blue
F335M - cyan
F360M - red

MIRI
F770W - blue
F1000W - orange
F1130W - green
F2100W - red

hubblesite writes
Blue: F435W (B) Green: F555W (V) Red: F656N (Halpha + [N II]) + F814 (I)

[VictorBorun]

for a classic barred galaxy NGC 1300
hubblesite has a H-alpha + IR image too
Blue: F435W (B) Green: F555W (V) Red: F814W (I) + F658N (H-alpha) [N II]

[VictorBorun]

M74 is regarded as the perfect spiral galaxy. Not only that, but it is regarded as the quintessential spiral galaxy without a bar.
Ann

to switch between Hubble and Robert Eder's Webb, I fitted and cropped

M74 h.jpg

Blue 0.435 μm, Green 0.555 μm, Red 0.656 μm narrow (H-alpha) + 0.814 μm

M74 w.jpg

Blue: 3 μm + 7.7 μm, Cyan 3.35 μm, Green: 11.3 μm, Yellow 2 μm, Orange 10 μm, Red 3.6 μm + 21 μm

Click to view full size image 1 or image 2

[Ann]

M74 is regarded as the perfect spiral galaxy. Not only that, but it is regarded as the quintessential spiral galaxy without a bar.
Ann

to switch between Hubble and Robert Eder's Webb, I fitted and cropped
M74 h.jpg Blue 0.435 μm, Green 0.555 μm, Red 0.656 μm narrow (H-alpha) + 0.814 μm
M74 w.jpg Blue: 3 μm + 7.7 μm, Cyan 3.35 μm, Green: 11.3 μm, Yellow 2 μm, Orange 10 μm, Red 3.6 μm + 21 μm

Click to view full size image 1 or image 2

Thanks, Victor, very nice!

Ann

[VictorBorun]

Thanks, Victor, very nice!
Ann

Here's a fitting of Judy Schmidt's Webb MIR (Red 21 μm, Orange 11.3 μm, Gray 10 μm, Cyan 7.7 μm)
to Hubble.
I failed to post a hangover pair

M74 w2.jpg

M74 h2.jpg

[VictorBorun]

2nd try to hang a pic over a pic

Click to view full size image 1 or image 2

[VictorBorun]

I wonder what the bright red dots are (21 μm).
They can't be brown dwarfs, that would be too faint to loom from another galaxy 30 million ly away.
Are they giant proto-stars in thick dust cloud of 20 μm particles, blocking all the shorter wavelengths?
A passing phase that lasts for, say, 10-100 years so we have never seen the like in Milky Way or Magellanic Cloud?

[Chris Peterson]

I wonder what the bright red dots are (21 μm).
They can't be brown dwarfs, that would be too faint to loom from another galaxy 30 million ly away.
Are they giant proto-stars in thick dust cloud of 20 μm particles, blocking all the shorter wavelengths?
A passing phase that lasts for, say, 10-100 years so we have never seen the like in Milky Way or Magellanic Cloud?

The bright red dots can't be isolated to the light from the 21 μm broad filter. Red is also made up of light from the 10 μm broad filter, the 3.6 μm medium filter (use: brown dwarfs, planets, continuum), and the 2 μm broad filter. So those red dots are a complex mix. To have a better idea what they represent, you'd need to examine the four separate channels that contribute to them.

[VictorBorun]

I wonder what the bright red dots are (21 μm).
They can't be brown dwarfs, that would be too faint to loom from another galaxy 30 million ly away.
Are they giant proto-stars in thick dust cloud of 20 μm particles, blocking all the shorter wavelengths?
A passing phase that lasts for, say, 10-100 years so we have never seen the like in Milky Way or Magellanic Cloud?

The bright red dots can't be isolated to the light from the 21 μm broad filter. Red is also made up of light from the 10 μm broad filter, the 3.6 μm medium filter (use: brown dwarfs, planets, continuum), and the 2 μm broad filter. So those red dots are a complex mix. To have a better idea what they represent, you'd need to examine the four separate channels that contribute to them.

But there are acid-red dots with no feed from other filters than «21 μm» wide filter

[Chris Peterson]

I wonder what the bright red dots are (21 μm).
They can't be brown dwarfs, that would be too faint to loom from another galaxy 30 million ly away.
Are they giant proto-stars in thick dust cloud of 20 μm particles, blocking all the shorter wavelengths?
A passing phase that lasts for, say, 10-100 years so we have never seen the like in Milky Way or Magellanic Cloud?

The bright red dots can't be isolated to the light from the 21 μm broad filter. Red is also made up of light from the 10 μm broad filter, the 3.6 μm medium filter (use: brown dwarfs, planets, continuum), and the 2 μm broad filter. So those red dots are a complex mix. To have a better idea what they represent, you'd need to examine the four separate channels that contribute to them.

But there are acid-red dots with no feed from other filters than «21 μm» wide filter

You determined that by looking at all four of those channels in grayscale?

[VictorBorun]

But there are acid-red dots with no feed from other filters than «21 μm» wide filter

You determined that by looking at all four of those channels in grayscale?

Here a few of red dots so purely red that they disappear if we remove red from RGB
(to please the eye I added a red channel = halfsum of green and blue)
And they have no counterpart in Hubble's pic

M74 w2 arrows at red dots.jpg

M74 w2 arrows.jpg

M74 h2 arrows.jpg

[Chris Peterson]

But there are acid-red dots with no feed from other filters than «21 μm» wide filter

You determined that by looking at all four of those channels in grayscale?

Here a few of red dots so purely red that they disappear if we remove red from RGB
(to please the eye I added a red channel = halfsum of green and blue)
And they have no counterpart in Hubble's pic
M74 w2 arrows at red dots.jpg
M74 w2 arrows.jpg
M74 h2 arrows.jpg

I would not attempt to draw any such conclusions from examining the color image.