James Webb Space Telescope zeroes in on the Cartwheel Galaxy

Shawn Knight

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What just happened? It's been less than a month since NASA released the first science data from the James Webb Space Telescope. Now that we've had time to soak in that incredible imagery, NASA has hit us with a new image set that again highlights how advanced Webb is compared to its predecessor.

The above image is a composite of the Cartwheel Galaxy from Webb's Near-Infrared Camera (NIRCam) and Mid-Infrared Instrument (MIRI). The galaxy is located around 500 million light-years away in the Sculptor constellation and is the result of a collision between a large spiral galaxy and a smaller galaxy. Here, it is flanked by two smaller companion galaxies against a backdrop of many others.

NASA said the bright center contains an enormous amount hot dust, and that the brightest areas are young star clusters. The outer ring of the galaxy has been expanding for about 440 million years and is roughly 1.5 times the size of our own Milky Way galaxy. As the ring swells, it collides with surrounding gas which triggers additional star formation.

NASA and the European Space Agency (ESA) previously imaged the Cartwheel Galaxy using the Hubble Space Telescope. Data from that observation was reprocessed in 2010 to bring out more detail in the image, but it still pales in comparison to what Webb was able to see using its cutting-edge instruments.

The blue, orange and yellow colors in the composite are elements from the NIRCam. NASA said the individual blue dots are stars or pockets of star formation. The shades of red from the MIRI reveal areas that are rich in hydrocarbons and other chemical compounds like silicate dust. It is these regions that make up the spiraling "skeleton" spokes of the galaxy.

The first batch of images from Webb included a look at the Southern Ring Nebula, Stephan's Quintet, the Carina Nebula, spectrum data from a giant exoplanet, and a stunning deep field observation.

Webb's latest observation is further evidence that the galaxy is in a transitory stage and will continue to evolve in the future.

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I like many of the images but I can't help but wonder how many of these would look without being colorized by NASA ..... or at least give us a side by side comparison ....
 
The images are not "colored" per se. These colors are created with the mix of images taken with different filters of the electromagnetic spectrum, in this case infrared, which is what the JWST instruments capture.

These procedures are to highlight relationships between the components of the observed objects.

on the nasa JWST storage site are the images of each filter and instrument, as public and open data. together with specialized software they can be integrated, mixed and processed. the images and the software are free and free, if you know how (and what) you can try making your own images.
 
Considering the sheer vastness of the universe, even if you accept the premise that we're the only intelligent life in this galaxy, there are over 200 *billion galaxies,* probably, just that we've observed so far. Even assuming the chance of life existing elsewhere is infinitesimally small, in such a vast universe, it's not a question of if it exists, just where.
 
I like many of the images but I can't help but wonder how many of these would look without being colorized by NASA ..... or at least give us a side by side comparison ....

They would be black.

Webb is an infrared telescope and can't deliver color pictures in the human visual range (maybe it can extend into the far red?). It's not going to deliver as many pretty pictures like the Hubble did, instead it's optimized for looking through dust in the IR to deliver more science in those under-researched wavelengths.

BTW the Hubble also frequently used false color, but the color shifts were within different parts of the human visual range so maybe that's why those look less "altered" to some people's eyes? They are less altered, but still not true color.

Even this from Hubble:


is false color though I thought galaxy pics might be true color. Nebula pics will always be false color as you're always trying to pick out certain emission lines in specific narrow wavelengths. You then map those to R G B or even one of the secondaries if they want.
 
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Considering the sheer vastness of the universe, even if you accept the premise that we're the only intelligent life in this galaxy, there are over 200 *billion galaxies,* probably, just that we've observed so far. Even assuming the chance of life existing elsewhere is infinitesimally small, in such a vast universe, it's not a question of if it exists, just where.
Yes, but it also means there's a big chance we'll never be able to find it.
 
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They would be black.

Webb is an infrared telescope and can't deliver color pictures in the human visual range (maybe it can extend into the far red?). It's not going to deliver as many pretty pictures like the Hubble did, instead it's optimized for looking through dust in the IR to deliver more science in those under-researched wavelengths.

BTW the Hubble also frequently used false color, but the color shifts were within different parts of the human visual range so maybe that's why those look less "altered" to some people's eyes? They are less altered, but still not true color.

Even this from Hubble:


is false color though I thought galaxy pics might be true color. Nebula pics will always be false color as you're always trying to pick out certain emission lines in specific narrow wavelengths. You then map those to R G B or even one of the secondaries if they want.
The webb can take color images but it's mainly designed to look in the infrared.
 
The images from Hubble, side by side with the James Webb, look a lot like most people
would see, setting their phones at 90 Hz, versus 120 Hz.
 
The webb can take color images but it's mainly designed to look in the infrared.
Webb can see orange and red visible light, but as you stated, Webb was designed to "see" primarily in the 750nm and longer region of the EM spectrum which is infrared and not visible to the human eye. It does not have the capabilities to see all the colors that the human eye does ~ 380nm - 750nm. https://jwst.nasa.gov/content/about/faqs/faqLite.html
Although Webb images will be infrared, this can be translated by computer into a visible picture (just like we have done with Spitzer, which has produced beautiful pictures as well). Additionally Webb can see orange and red visible light.
Lots of things in the universe are obscured by dust. Webb was designed to see through that dust by using infrared wavelengths.
 
And the funny thing about that obscuring dust: Why don't we just have big observatories on Earth looking in IR? Well there are a few but they're inefficient because:

Water absorbs at IR wavelengths. Dammit! Stupid atmosphere.
 
Stupid question, but does anything we’re looking at with this thing even exist anymore? Is there something out there only 1 light year away that I should be concerned about? Am I thinking about this correctly or am I just an *****?
 
Stupid question, but does anything we’re looking at with this thing even exist anymore? Is there something out there only 1 light year away that I should be concerned about? Am I thinking about this correctly or am I just an *****?

The Milky Way is over 10 billion years old (conservative estimate) and with the universe being less than 14 billion years old, it's an easy assumption that all these galaxies are still around doing their gravitationally-driven thing. How relevant is that to day to day life....? Not much? But it's cool to know what's out there.

Is something unknown a light year away of concern, yeah certainly could be. Not so much concern itself, but if it has a lot of mass, it could be gravitationally diverting other things every which way and one of those ways could be towards us.

I haven't looked this up but since JWST is an IR telescope it could be well suited to doing some sort of targeted scan for large but dim objects that retain some of their warmth (even tiny Pluto has some warmth), thus be visible in the IR range. The problem is that All-Sky scans usually use a telescope that can image a decent area of sky at a time and I don't know how "wide" JWST can go. All the images so far have been pretty narrow but if it can take pics quickly, it can then take a big set of them to cover the area of interest.
 
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Ye
Webb can see orange and red visible light, but as you stated, Webb was designed to "see" primarily in the 750nm and longer region of the EM spectrum which is infrared and not visible to the human eye. It does not have the capabilities to see all the colors that the human eye does ~ 380nm - 750nm. https://jwst.nasa.gov/content/about/faqs/faqLite.html
Lots of things in the universe are obscured by dust. Webb was designed to see through that dust by using infrared wavelengths.
 
Yet more pretty space pictures. How does this bode for scientific advancement?

Don't tell us all that money were spent to make posters for space aficionados.
 
since JWST is an IR telescope it could be well suited to doing some sort of targeted scan for large but dim objects that retain some of their warmth (even tiny Pluto has some warmth), thus be visible in the IR range
JWST doesn't see in LWIR. Its near-infrared instruments see down to about 2500nm. According to my blackbody calculator, that's a temperature of about 900C (though obviously cooler objects would still radiate somewhat in that spectrum).
 
Pluto's average temperature of 44K has a peak blackbody radiation at about 66,000nm which is outside that of the MIR instrument and is down by an order of magnitude at 28,500nm unfortunately. I didn't realize that searching for relatively cold (but not 4K background cold!) objects was outside the Webb's design.
 
Yet more pretty space pictures. How does this bode for scientific advancement?

Don't tell us all that money were spent to make posters for space aficionados.
Can you please just go live in a cave somewhere and leave the rest of the scientific and tech world alone? As that otherwise seems the limit of your ambitions for our species.
 
Pluto's average temperature of 44K has a peak blackbody radiation at about 66,000nm which is outside that of the MIR instrument and is down by an order of magnitude at 28,500nm unfortunately. I didn't realize that searching for relatively cold (but not 4K background cold!) objects was outside the Webb's design.
Unless there is something that we are missing with JWST, or the author of this article just does not know what they are talking about https://www.space.com/james-webb-space-telescope-kuiper-belt-objects There are, apparently, plans for scientific study of Kuiper belt objects - including Pluto. Based on your analysis of the Black Body Spectrum of Pluto, one would think that Pluto and other Kuiper belt objects would be outside of the range of JWST's instrumentation. To sort of answer my own question with an old article - https://asd.gsfc.nasa.gov/blueshift/index.php/2015/07/08/pluto/
The James Webb Space Telescope will offer further insight and follow-up for the New Horizons findings. While imaging Pluto with JWST is not nearly as defined, offering only a few pixels across, the unprecedented spectral sensitivity and factor of ~6 in spectral resolution will allow for the detection of new species, determine isotope ratios, and routinely measure the water and methane temperatures on the planet. Regular observations of these volatiles and ices will provide details on seasonal variation in the composition. Pluto experiences solstice in 2029, and may express significant changes in abundance and perhaps composition as that time approaches.
So it is not only the emission of a body as a black body radiator, but the spectroscopic emissions, and, perhaps, absorbtion of various elements that can also be studied.

Personally, I have not dug deeply into the question, however, the spectroscopy of other elements will also come into play in the study of these cold bodies.
 
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Outside of MIRI, but just about within NIRcam (and NIRspec), and while the peak is at 66 microns, there's still a substantial emission beyond that:
View attachment 88404

Thanks for this! Because I could swear that I'd heard long ago that JWST could search for slightly warm bodies like Planet 9 and other maybe-largish things hanging about in the Oort Cloud or farther but I frequently have trouble keeping the wavelengths straight that all the instruments cover.
 
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