APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Comments and questions about the APOD on the main view screen.
User avatar
APOD Robot
Otto Posterman
Posts: 5453
Joined: Fri Dec 04, 2009 3:27 am

APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by APOD Robot » Thu Apr 25, 2024 4:06 am

Image NGC 604: Giant Stellar Nursery

Explanation: Located some 3 million light-years away in the arms of nearby spiral galaxy M33, giant stellar nursery NGC 604 is about 1,300 light-years across. That's nearly 100 times the size of the Milky Way's Orion Nebula, the closest large star forming region to planet Earth. In fact, among the star forming regions within the Local Group of galaxies, NGC 604 is second in size only to 30 Doradus, also known as the Tarantula Nebula in the Large Magellanic Cloud. Cavernous bubbles and cavities in NGC 604 fill this stunning infrared image from the James Webb Space Telescope's NIRCam. They are carved out by energetic stellar winds from the region's more than 200 hot, massive, young stars, all still in early stages of their lives.

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

User avatar
Ann
4725 Å
Posts: 13597
Joined: Sat May 29, 2010 5:33 am

Re: APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by Ann » Thu Apr 25, 2024 5:07 am

I have two favorite images of NGC 604. Today's APOD is not one of them.

Let's start with the Chandra portrait of NGC 604:


APOD 25 April 2024 annotated.png
Possible location of the Chandra bubbles in the APOD.
Maybe it's just the right-hand bubble that is seen in the Chandra image.
Chandra X-ray Observatory wrote:

This composite image from Chandra X-ray Observatory data (colored blue), combined with optical light data from the Hubble Space Telescope (red and green), shows a divided neighborhood where some 200 hot, young, massive stars reside.
However, there is a difference between the two sides of this bifurcated stellar city. On the western (right) side, the amount of hot gas found in the bubbles corresponds to about 4300 times the mass of the sun. This value and the brightness of the gas in X-rays imply that the western part of NGC 604 is entirely powered by winds from the 200 hot massive stars.
The situation is different on the eastern (left) side of NGC 604. On this side, the X-ray gas contains 1750 times the mass of the sun and winds from young stars cannot explain the brightness of the X-ray emission. The bubbles on this side appear to be much older and were likely created and powered by young stars and supernovas in the past.
Wow! We are witnessing how star formation is progressing from one part of a giant molecular cloud to another.


All right! My second favorite picture of NGC 604 is one by Hubble:


I was disappointed when I first saw the Hubble portrait of M33, because I thought that the picture was so overwhelmingly yellow and monotonous. I was used to seeing M33 with a lot of blue stars and pink nebulas, the way it looks in the picture by Adam Block... wait... what's that tiny blue object at upper right in the Hubble image?

NGC 604 Hubble.png

It's NGC 604! It is! :D

The Hubble picture really puts NGC 604 in its place. It is so small compared with M33 itself, but it stands out incredibly.

Ann
You do not have the required permissions to view the files attached to this post.
Last edited by Ann on Fri Apr 26, 2024 4:19 am, edited 1 time in total.
Color Commentator

Christian G.
Science Officer
Posts: 186
Joined: Sat Apr 08, 2023 10:37 pm

Re: APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by Christian G. » Thu Apr 25, 2024 2:37 pm

I'm still somewhat puzzled by JWST colour choices. Is there a scientific reason why they chose pink/red for NGC 604 but a kind of rusty brownish not-really-red for the Tarantula Nebula? Is it to reflect different molecular properties or are these different colours for no real reason?

604.png
2070.jpg
You do not have the required permissions to view the files attached to this post.

User avatar
Chris Peterson
Abominable Snowman
Posts: 18387
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by Chris Peterson » Thu Apr 25, 2024 2:54 pm

Christian G. wrote: Thu Apr 25, 2024 2:37 pm I'm still somewhat puzzled by JWST colour choices. Is there a scientific reason why they chose pink/red for NGC 604 but a kind of rusty brownish not-really-red for the Tarantula Nebula? Is it to reflect different molecular properties or are these different colours for no real reason?


604.png
2070.jpg
Where did you find the Tarantula image? (And to me, it looks like both the images you provided are using the same palette.)
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com

Christian G.
Science Officer
Posts: 186
Joined: Sat Apr 08, 2023 10:37 pm

Re: APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by Christian G. » Thu Apr 25, 2024 3:19 pm

Chris Peterson wrote: Thu Apr 25, 2024 2:54 pm
Christian G. wrote: Thu Apr 25, 2024 2:37 pm I'm still somewhat puzzled by JWST colour choices. Is there a scientific reason why they chose pink/red for NGC 604 but a kind of rusty brownish not-really-red for the Tarantula Nebula? Is it to reflect different molecular properties or are these different colours for no real reason?


604.png
2070.jpg
Where did you find the Tarantula image? (And to me, it looks like both the images you provided are using the same palette.)
I found it here: https://www.nasa.gov/universe/a-cosmic- ... asas-webb/

User avatar
Chris Peterson
Abominable Snowman
Posts: 18387
Joined: Wed Jan 31, 2007 11:13 pm
Location: Guffey, Colorado, USA

Re: APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by Chris Peterson » Thu Apr 25, 2024 3:55 pm

Christian G. wrote: Thu Apr 25, 2024 3:19 pm
Chris Peterson wrote: Thu Apr 25, 2024 2:54 pm
Christian G. wrote: Thu Apr 25, 2024 2:37 pm I'm still somewhat puzzled by JWST colour choices. Is there a scientific reason why they chose pink/red for NGC 604 but a kind of rusty brownish not-really-red for the Tarantula Nebula? Is it to reflect different molecular properties or are these different colours for no real reason?


604.png
2070.jpg
Where did you find the Tarantula image? (And to me, it looks like both the images you provided are using the same palette.)
I found it here: https://www.nasa.gov/universe/a-cosmic- ... asas-webb/
It's unclear what mapping was used in either image, or indeed, which filters. As a rule, color images have little scientific value. They are created for press releases and education, not science. So the choice of colors is often aesthetic, or intended to emphasize particular structure. This is particularly true where some or all of the data is completely outside the human visual spectrum, and where more than three filters are used.
Chris

*****************************************
Chris L Peterson
Cloudbait Observatory
https://www.cloudbait.com

User avatar
AVAO
Commander
Posts: 615
Joined: Tue May 28, 2019 12:24 pm
AKA: multiwavelength traveller
Location: Zurich, Switzerland

Re: APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by AVAO » Thu Apr 25, 2024 5:19 pm

Chris Peterson wrote: Thu Apr 25, 2024 3:55 pm
Christian G. wrote: Thu Apr 25, 2024 3:19 pm
Chris Peterson wrote: Thu Apr 25, 2024 2:54 pm

Where did you find the Tarantula image? (And to me, it looks like both the images you provided are using the same palette.)
I found it here: https://www.nasa.gov/universe/a-cosmic- ... asas-webb/
It's unclear what mapping was used in either image, or indeed, which filters. As a rule, color images have little scientific value. They are created for press releases and education, not science. So the choice of colors is often aesthetic, or intended to emphasize particular structure. This is particularly true where some or all of the data is completely outside the human visual spectrum, and where more than three filters are used.
Chris' comments are certainly correct.

In addition, simply add the following information:
The filters F090W, F200W, F335M, F444W were used for both images.
In the image of NGC 604, F187N (cyan) and F470N (intense red) were also used,
which is why the inner clouds turn into white-blue and the outer clouds turn into intense red.

In fact, the pictures are not really comparable...




...I love this treasure chest far away... jac berne (flickr) artistic composit, mixed sources
Last edited by AVAO on Fri Apr 26, 2024 10:25 am, edited 2 times in total.

User avatar
VictorBorun
Captain
Posts: 1082
Joined: Fri Oct 16, 2020 10:25 pm

Re: APOD: NGC 604: Giant Stellar Nursery (2024 Apr 25)

Post by VictorBorun » Thu Apr 25, 2024 7:04 pm

Ann wrote: Thu Apr 25, 2024 5:07 am Let's start with my Chandra portrait of NGC 604:
APOD 25 April 2024 annotated.png
Possible location of the Chandra bubbles in the APOD.
Maybe it's just the right-hand bubble that is seen in the Chandra image.
Chandra X-ray Observatory wrote:

This composite image from Chandra X-ray Observatory data (colored blue), combined with optical light data from the Hubble Space Telescope (red and green), shows a divided neighborhood where some 200 hot, young, massive stars reside.
However, there is a difference between the two sides of this bifurcated stellar city. On the western (right) side, the amount of hot gas found in the bubbles corresponds to about 4300 times the mass of the sun. This value and the brightness of the gas in X-rays imply that the western part of NGC 604 is entirely powered by winds from the 200 hot massive stars.
The situation is different on the eastern (left) side of NGC 604. On this side, the X-ray gas contains 1750 times the mass of the sun and winds from young stars cannot explain the brightness of the X-ray emission. The bubbles on this side appear to be much older and were likely created and powered by young stars and supernovas in the past.
Wow! We are witnessing how star formation is progressing from one part of a giant molecular cloud to another.


Ann
NGC 604-Giant Stellar Nursery (2024 Apr 25)..jpg
Click to view full size image 1 or image 2
your Possible location of the Chandra bubbles in the APOD fits just fine
You do not have the required permissions to view the files attached to this post.