WEBB: JWST peers into the extreme outer galaxy

[AVAO]

NASA’s Webb Peers Into Digel Cloud 1/2 in the Extreme Outer Galaxy
universetoday.com | Original release 2024 September 13

This JWST image shows a region of rapid star formation in the Extreme Outer Galaxy. It's part of what's called Digel Cloud 2, one of two clouds that each hold multiple regions of rapid star formation. This area is called Digel Cloud 2S and contains a luminous main cluster full of bright young stars. Image Credit: NASA, ESA, CSA, STScI, M. Ressler (NASA-JPL)

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The Milky Way’s outer reaches are coming into view thanks to the JWST. Astronomers pointed the powerful space telescope to a region over 58,000 light-years away called the Extreme Outer Galaxy (EOG). They found star clusters exhibiting extremely high rates of star formation.T

A team of astronomers used the JWST’s powerful NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to examine star formation in two specific regions of the EOG. They’re molecular clouds named Digel Cloud 1 and Digel Cloud 2. They’re named after the astronomer Seth Digel, who discovered them in 1994.
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“What was fascinating and astounding to me from the Webb data is that there are multiple jets shooting out in all different directions from this cluster of stars.” Mike Ressler, NASA’s Jet Propulsion Laboratory

...more...

The image above shows Digel Cloud 2S

Click to view full size image

This image from the research gives the overall context of the Digel Clouds in galactic coordinates. Star formation in Cloud 2N was likely triggered by a nearby huge supernova remnant, according to the authors. Izumi et al. 2024.

BSN4Y Jac

[Ann]

NASA’s Webb Peers Into Digel Cloud 1/2 in the Extreme Outer Galaxy
universetoday.com | Original release 2024 September 13

This JWST image shows a region of rapid star formation in the Extreme Outer Galaxy. It's part of what's called Digel Cloud 2, one of two clouds that each hold multiple regions of rapid star formation. This area is called Digel Cloud 2S and contains a luminous main cluster full of bright young stars. Image Credit: NASA, ESA, CSA, STScI, M. Ressler (NASA-JPL)

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The Milky Way’s outer reaches are coming into view thanks to the JWST. Astronomers pointed the powerful space telescope to a region over 58,000 light-years away called the Extreme Outer Galaxy (EOG). They found star clusters exhibiting extremely high rates of star formation.T

A team of astronomers used the JWST’s powerful NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to examine star formation in two specific regions of the EOG. They’re molecular clouds named Digel Cloud 1 and Digel Cloud 2. They’re named after the astronomer Seth Digel, who discovered them in 1994.
[...]

“What was fascinating and astounding to me from the Webb data is that there are multiple jets shooting out in all different directions from this cluster of stars.” Mike Ressler, NASA’s Jet Propulsion Laboratory

...more...

The image above shows Digel Cloud 2S

Click to view full size image

This image from the research gives the overall context of the Digel Clouds in galactic coordinates. Star formation in Cloud 2N was likely triggered by a nearby huge supernova remnant, according to the authors. Izumi et al. 2024.

BSN4Y Jac

I was thrilled that Webb has found fresh star formation in the outer reaches of our galaxy, probably pretty far from the "visible edge of the disk"! (And I know that there is a definition of "the visible edge of a galactic disk", but I'm too lazy to google it.)

In any case, I just love it when galaxies form fresh new blue stars far from the visible galactic disk. The perfect example of this is NGC 1512:

NGC 1512 and its satellite galaxy NGC 1510 in visible light. Credit: NASA, ESA, Hubble.

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NGC 1512 and its satellite galaxy NGC 1510 in ultraviolet light. Credit: NASA/Caltech-JPL

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The ultraviolet light of the outer arms of NGC 1512 comes from stars of spectral classes O, B and also early A, like Vega. I love the idea that our own galaxy might have, if not proper ultraviolet arms, at least "outlying clusters" of hot stars that would stand out in ultraviolet light.

So my question is, does Digel Cloud 25 contain stars of at least spectral class A0, like Vega? Or is Digel Cloud 25 home to nothing but clusters made of faint little low-mass stars typically no more massive than the Sun?

Consider IC 4603 in Ophiuchus. This is a new Webb picture of the are and a caption from Wikipedia:

Two stars are visible in IC 4603 (the brightest part of this picture). I guess that the brightest one is the star S1 of IC 4603. I would guess that it is at least spectral class A0, with a mass at least similar to Vega. Credit: Bob Franke.

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The Rho Ophiuchi cloud complex with star formation in IC 4603. Wikipedia wrote: 'The young stars at the centre of many of these discs are similar in mass to the Sun or smaller. The heftiest in this image is the star S1, which appears amid a glowing cave it is carving out with its stellar winds in the lower half of the image.' Credit: NASA, ESA, CSA, STScI, K. Pontoppidan (STScI), A. Pagan (STScI)

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I guess the orientation of the two IC 4603 images is not the same!

But in any case, I think it is hard to find a young cluster consisting of solar mass and still lower mass stars only. Practically all young clusters appear to contain at least one star of at least spectral class A0, like Vega.

I hope the newly discovered extreme outer galaxy clusters do too!

Ann

[AVAO]

NASA’s Webb Peers Into Digel Cloud 1/2 in the Extreme Outer Galaxy
universetoday.com | Original release 2024 September 13

This JWST image shows a region of rapid star formation in the Extreme Outer Galaxy. It's part of what's called Digel Cloud 2, one of two clouds that each hold multiple regions of rapid star formation. This area is called Digel Cloud 2S and contains a luminous main cluster full of bright young stars. Image Credit: NASA, ESA, CSA, STScI, M. Ressler (NASA-JPL)

---

The Milky Way’s outer reaches are coming into view thanks to the JWST. Astronomers pointed the powerful space telescope to a region over 58,000 light-years away called the Extreme Outer Galaxy (EOG). They found star clusters exhibiting extremely high rates of star formation.T

A team of astronomers used the JWST’s powerful NIRCam (Near-Infrared Camera) and MIRI (Mid-Infrared Instrument) to examine star formation in two specific regions of the EOG. They’re molecular clouds named Digel Cloud 1 and Digel Cloud 2. They’re named after the astronomer Seth Digel, who discovered them in 1994.
[...]

“What was fascinating and astounding to me from the Webb data is that there are multiple jets shooting out in all different directions from this cluster of stars.” Mike Ressler, NASA’s Jet Propulsion Laboratory

...more...

The image above shows Digel Cloud 2S

Click to view full size image

This image from the research gives the overall context of the Digel Clouds in galactic coordinates. Star formation in Cloud 2N was likely triggered by a nearby huge supernova remnant, according to the authors. Izumi et al. 2024.

BSN4Y Jac

I was thrilled that Webb has found fresh star in the outer reaches of our galaxy, probably pretty far from the "visible edge of the disk"! (And I know that there is a definition of that, but I'm too lazy to google it.)

[...]

I hope the newly discovered extreme outer galaxy clusters do too!

Ann

very cool Ann

A cosmic kindergarten in the Milky Way: The Digel Cloud 2 is located in the outer regions of our Milky Way, more than 58,000 light years from the galactic center. This means that the light we receive today from this star-forming region left this region more than 58,000 years ago.
(verified by gemini)

Jac

[Christian G.]

A pretty cluster image! And upon seeing it, I thought of the opposite, an innermost cluster, the Quintuplet, I hope JWST peers into this one too! Before it gets ripped apart.

Hubble

[AVAO]

A pretty cluster image! And upon seeing it, I thought of the opposite, an innermost cluster, the Quintuplet, I hope JWST peers into this one too! Before it gets ripped apart. weic2422a-2000x1200-1.jpgQ.jpg
Hubble

Interesting comparison. Thanks.

Click to view full size image

Image of the Quintuplet cluster's brightest stars; V4998 Sagittarii, The Pistol star, and qF362

Hubble Space Telescope image of the Quintuplet Cluster region. The Pistol Star is seen in the middle, surrounded by its ejection nebula. The luminous blue variable (LBV) star G0.120−0.048 is at the upper right, surrounded by a spherical nebula, believed to have been ejected by that star. LBV qF362 to the left of the Pistol Star also seems to be surrounded by a low-level nebular emission.

Click to view full size image

One of the intrinsically brightest stars in our galaxy appears as the bright white dot in the center of this image taken with NASA's Hubble Space Telescope. Hubble's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) was needed to take the picture, because the star is hidden at the galactic center, behind obscuring dust. NICMOS' infrared vision penetrated the dust to reveal the star, which is glowing with the radiance of 10 million suns. The image also shows one of the most massive stellar eruptions ever seen in space. The radiant star has enough raw power to blow off two expanding shells (magenta) of gas equal to the mass of several of our suns. The largest shell is so big (4 light-years) it would stretch nearly all the way from our Sun to the next nearest star. The outbursts seen by Hubble are estimated to be only 4,000 and 6,000 years old, respectively. Despite such a tremendous mass loss, astronomers estimate the extraordinary star may presently be 100 times more massive than our Sun, and may have started with as much as 200 solar masses of material, but it is violently shedding much of its mass. The star is 25,000 light-years away in the direction of the constellation Sagittarius. Despite its great distance, the star would be visible to the naked eye as a modest 4th magnitude object if it were not for the dust between it and the Earth. This false-colored image is a composite of two separately filtered images taken with the NICMOS, on September 13,1997. The field of view is 4.8 light-years across, at the star's distance of 25,000 light-years. Resolution is 0.075 arc seconds per pixel (picture element).