APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

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Expand view Topic review: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by VictorBorun » Fri Aug 26, 2022 1:14 am

Chris Peterson wrote: Thu Jul 28, 2022 6:24 pm
There are four wheels, two each for the long wavelength channel and the short wavelength channel (which have different optical paths). They are often used in combination. For instance, when the F323N filter (long wavelength pupil wheel) is used, it is typically paired with the F322W2 filter (long wavelength filter wheel) for blocking purposes.

This image was constructed from two data channels, one imaged through the F323N/F322W2 pair, and the other through the F212N filter (short wavelength filter wheel).
I finally got what you were saying all along: one of the 2 near-IR wheels has no clear filter and must be positioned as to let the light pass one of the wide filter surrogate
two wheels.jpg

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Wed Aug 03, 2022 2:53 pm

bystander wrote: Wed Aug 03, 2022 2:31 pm
Chris Peterson wrote: Wed Aug 03, 2022 2:05 pm Well, if you have three or less channels going in, and you map them directly to some combination of red, green, and blue, nothing is lost. But, as you say, details will be more or less visible to our eyes depending on the order of the mapping. If you have more than three input channels, or channels that are mapped to mixes of RGB (e.g. a channel mapped to yellow) then you lose information in the final image.
I know it probably doesn't come up much, but what about CMY (or CMYK)? Would you have information loss with that?
I don't know of any display devices that use CMY. Subtractive color schemes like CMY are used in printing. They also have a smaller gamut, so there is more possibility for information loss. But in principle, the same thing applies to any mapping. The main point for not losing information is that the input channels be mapped to native output channels, not to mixes of those channels.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by bystander » Wed Aug 03, 2022 2:31 pm

Chris Peterson wrote: Wed Aug 03, 2022 2:05 pm Well, if you have three or less channels going in, and you map them directly to some combination of red, green, and blue, nothing is lost. But, as you say, details will be more or less visible to our eyes depending on the order of the mapping. If you have more than three input channels, or channels that are mapped to mixes of RGB (e.g. a channel mapped to yellow) then you lose information in the final image.
I know it probably doesn't come up much, but what about CMY (or CMYK)? Would you have information loss with that?

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by johnnydeep » Wed Aug 03, 2022 2:23 pm

Chris Peterson wrote: Wed Aug 03, 2022 2:05 pm
johnnydeep wrote: Wed Aug 03, 2022 1:54 pm
Chris Peterson wrote: Wed Aug 03, 2022 1:09 pm

I just mean a mapping where longer wavelengths in the source correspond to longer ones in the final image. And that does not necessarily result in the clearest image.
Alright. So the details are still present (i.e., not totally lost), just obscured to our eyes due to the mapping choice.
Well, if you have three or less channels going in, and you map them directly to some combination of red, green, and blue, nothing is lost. But, as you say, details will be more or less visible to our eyes depending on the order of the mapping. If you have more than three input channels, or channels that are mapped to mixes of RGB (e.g. a channel mapped to yellow) then you lose information in the final image.
Ok, got it.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Wed Aug 03, 2022 2:05 pm

johnnydeep wrote: Wed Aug 03, 2022 1:54 pm
Chris Peterson wrote: Wed Aug 03, 2022 1:09 pm
johnnydeep wrote: Wed Aug 03, 2022 1:00 pm

I would think any true one-to-one mapping of input to output wavelengths would preserve all detail, though it could be less visible if the output range is compressed versus the input range. And on the other hand a many to one mapping would clearly lose info/detail, and a one to many mapping might show false details that don't exist in reality. Or am I misunderstanding yet again?
I just mean a mapping where longer wavelengths in the source correspond to longer ones in the final image. And that does not necessarily result in the clearest image.
Alright. So the details are still present (i.e., not totally lost), just obscured to our eyes due to the mapping choice.
Well, if you have three or less channels going in, and you map them directly to some combination of red, green, and blue, nothing is lost. But, as you say, details will be more or less visible to our eyes depending on the order of the mapping. If you have more than three input channels, or channels that are mapped to mixes of RGB (e.g. a channel mapped to yellow) then you lose information in the final image.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by johnnydeep » Wed Aug 03, 2022 1:54 pm

Chris Peterson wrote: Wed Aug 03, 2022 1:09 pm
johnnydeep wrote: Wed Aug 03, 2022 1:00 pm
Chris Peterson wrote: Tue Aug 02, 2022 7:22 pm
Yes. Not the best word choice, but a hard thing to describe without a lot of words. We have been somewhat consistently using it in several discussions to refer to a mapping where there is a one-to-one correspondence between the input and output wavelengths. (Still not great wording, but hopefully you get the drift.)
I would think any true one-to-one mapping of input to output wavelengths would preserve all detail, though it could be less visible if the output range is compressed versus the input range. And on the other hand a many to one mapping would clearly lose info/detail, and a one to many mapping might show false details that don't exist in reality. Or am I misunderstanding yet again?
I just mean a mapping where longer wavelengths in the source correspond to longer ones in the final image. And that does not necessarily result in the clearest image.
Alright. So the details are still present (i.e., not totally lost), just obscured to our eyes due to the mapping choice.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Wed Aug 03, 2022 1:09 pm

johnnydeep wrote: Wed Aug 03, 2022 1:00 pm
Chris Peterson wrote: Tue Aug 02, 2022 7:22 pm
johnnydeep wrote: Tue Aug 02, 2022 7:00 pm

I'm probably showing my ignorance again, but isn't the second encoding still monotonic, just opposite in direction to the first?
Yes. Not the best word choice, but a hard thing to describe without a lot of words. We have been somewhat consistently using it in several discussions to refer to a mapping where there is a one-to-one correspondence between the input and output wavelengths. (Still not great wording, but hopefully you get the drift.)
I would think any true one-to-one mapping of input to output wavelengths would preserve all detail, though it could be less visible if the output range is compressed versus the input range. And on the other hand a many to one mapping would clearly lose info/detail, and a one to many mapping might show false details that don't exist in reality. Or am I misunderstanding yet again?
I just mean a mapping where longer wavelengths in the source correspond to longer ones in the final image. And that does not necessarily result in the clearest image.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by johnnydeep » Wed Aug 03, 2022 1:00 pm

Chris Peterson wrote: Tue Aug 02, 2022 7:22 pm
johnnydeep wrote: Tue Aug 02, 2022 7:00 pm
Chris Peterson wrote: Tue Aug 02, 2022 4:45 pm

Which demonstrates exactly why monotonic coding can be a very bad idea. The first mapping shows MUCH more detail than the second.
I'm probably showing my ignorance again, but isn't the second encoding still monotonic, just opposite in direction to the first?
Yes. Not the best word choice, but a hard thing to describe without a lot of words. We have been somewhat consistently using it in several discussions to refer to a mapping where there is a one-to-one correspondence between the input and output wavelengths. (Still not great wording, but hopefully you get the drift.)
I would think any true one-to-one mapping of input to output wavelengths would preserve all detail, though it could be less visible if the output range is compressed versus the input range. And on the other hand a many to one mapping would clearly lose info/detail, and a one to many mapping might show false details that don't exist in reality. Or am I misunderstanding yet again?

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Tue Aug 02, 2022 7:22 pm

johnnydeep wrote: Tue Aug 02, 2022 7:00 pm
Chris Peterson wrote: Tue Aug 02, 2022 4:45 pm
VictorBorun wrote: Tue Aug 02, 2022 4:32 pm

the rgb coding is inverse:
2.0 μm ↦ red
2.14 μm ↦ green
2.16 μm ↦ blue


If we change the coding to
2.0 μm ↦ blue
2.14 μm ↦ green
2.16 μm ↦ red
Sharpening up Jupiter.jpg
Which demonstrates exactly why monotonic coding can be a very bad idea. The first mapping shows MUCH more detail than the second.
I'm probably showing my ignorance again, but isn't the second encoding still monotonic, just opposite in direction to the first?
Yes. Not the best word choice, but a hard thing to describe without a lot of words. We have been somewhat consistently using it in several discussions to refer to a mapping where there is a one-to-one correspondence between the input and output wavelengths. (Still not great wording, but hopefully you get the drift.)

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by johnnydeep » Tue Aug 02, 2022 7:00 pm

Chris Peterson wrote: Tue Aug 02, 2022 4:45 pm
VictorBorun wrote: Tue Aug 02, 2022 4:32 pm
sallyseaver wrote: Sat Jul 30, 2022 11:33 am
the rgb coding is inverse:
2.0 μm ↦ red
2.14 μm ↦ green
2.16 μm ↦ blue


If we change the coding to
2.0 μm ↦ blue
2.14 μm ↦ green
2.16 μm ↦ red
Sharpening up Jupiter.jpg
Which demonstrates exactly why monotonic coding can be a very bad idea. The first mapping shows MUCH more detail than the second.
I'm probably showing my ignorance again, but isn't the second encoding still monotonic, just opposite in direction to the first?

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Tue Aug 02, 2022 4:45 pm

VictorBorun wrote: Tue Aug 02, 2022 4:32 pm
sallyseaver wrote: Sat Jul 30, 2022 11:33 am
the rgb coding is inverse:
2.0 μm ↦ red
2.14 μm ↦ green
2.16 μm ↦ blue


If we change the coding to
2.0 μm ↦ blue
2.14 μm ↦ green
2.16 μm ↦ red
Sharpening up Jupiter.jpg
Which demonstrates exactly why monotonic coding can be a very bad idea. The first mapping shows MUCH more detail than the second.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by VictorBorun » Tue Aug 02, 2022 4:32 pm

sallyseaver wrote: Sat Jul 30, 2022 11:33 am
the rgb coding is inverse:
2.0 μm ↦ red
2.14 μm ↦ green
2.16 μm ↦ blue


If we change the coding to
2.0 μm ↦ blue
2.14 μm ↦ green
2.16 μm ↦ red
Sharpening up Jupiter.jpg

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by sallyseaver » Mon Aug 01, 2022 3:01 pm

The dog image is single channel (that is, grayscale data) mapped to a pseudocolor palette. It is in a wavelength band that represents energy being emitted from the dog, not reflected in any way. Intensity has been mapped to color, so whether brighter is hotter is purely dependent upon the chosen palette.

The Jupiter image is constructed from multichannel data assigned to a false color palette. Again, we are not seeing reflected IR but emitted IR. In general, for any single channel, the signal strength is proportional to temperature. But a longer wavelength will show cooler temperatures, so as soon as you combine two or more wavelength channels, you can no longer assume that what is brightest in the image is also the warmest. You need to consider the intensity in each channel separately to make any unambiguous assessment of temperature.
Chris, Thank you for straightening me out about the temperature interpretation of the IR imaging. I know about black body radiation, of course, but I obviously need more understanding about how this meshes with the usual absorption and refraction of incident EM waves in the IR range.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Sat Jul 30, 2022 1:22 pm

sallyseaver wrote: Sat Jul 30, 2022 11:33 am Judy/Geckzilla, who processed the JWST data, confirmed the following on https://geckzilla.com/:
Red (screen): NIRCam F322W2-F323N (this is not a subtraction function, both filters were used at the same time)
Blue: NIRCam F212N
Background is a grayscale combination of both filters. There were gaps in the data that had to be filled in using either filter to complete the other.
This page, https://jwst-docs.stsci.edu/jwst-near-i ... am-filters, shows the wavelengths involved for these filters:
F322W-F323N: 2.5 to 4.1 microns
F212N: 2.1 to 2.15 microns

This page from NASA, https://science.nasa.gov/ems/07_infraredwaves, has an interesting discussion related to interpreting infrared [IR] imaging.

It has some images showing a calibration between temp and colors in a dog image. This Jupiter image is not calibrated to specific temperatures but we can get a sense of hot and cold. Here is my reasoning.

Consider the image of the dog at the NASA page noted above.
Image
Consider that the light areas of the IR image go with areas of the dog where the temp is high and IR energy is reflected (not absorbed). Dark areas of the IR image go with areas of the dog where temp is not high and IR energy is absorbed.
The dog image is single channel (that is, grayscale data) mapped to a pseudocolor palette. It is in a wavelength band that represents energy being emitted from the dog, not reflected in any way. Intensity has been mapped to color, so whether brighter is hotter is purely dependent upon the chosen palette.

The Jupiter image is constructed from multichannel data assigned to a false color palette. Again, we are not seeing reflected IR but emitted IR. In general, for any single channel, the signal strength is proportional to temperature. But a longer wavelength will show cooler temperatures, so as soon as you combine two or more wavelength channels, you can no longer assume that what is brightest in the image is also the warmest. You need to consider the intensity in each channel separately to make any unambiguous assessment of temperature.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by sallyseaver » Sat Jul 30, 2022 11:33 am

Judy/Geckzilla, who processed the JWST data, confirmed the following on https://geckzilla.com/:
Red (screen): NIRCam F322W2-F323N (this is not a subtraction function, both filters were used at the same time)
Blue: NIRCam F212N
Background is a grayscale combination of both filters. There were gaps in the data that had to be filled in using either filter to complete the other.
This page, https://jwst-docs.stsci.edu/jwst-near-i ... am-filters, shows the wavelengths involved for these filters:
F322W-F323N: 2.5 to 4.1 microns
F212N: 2.1 to 2.15 microns

This page from NASA, https://science.nasa.gov/ems/07_infraredwaves, has an interesting discussion related to interpreting infrared [IR] imaging.

It has some images showing a calibration between temp and colors in a dog image. This Jupiter image is not calibrated to specific temperatures but we can get a sense of hot and cold. Here is my reasoning.

Consider the image of the dog at the NASA page noted above.
Image
Consider that the light areas of the IR image go with areas of the dog where the temp is high and IR energy is reflected (not absorbed). Dark areas of the IR image go with areas of the dog where temp is not high and IR energy is absorbed.

Quoted from the above NASA page,
Infrared waves have longer wavelengths than visible light and can pass through dense regions of gas and dust in space with less scattering and absorption.


In the JWST image of Jupiter processed by Geckzilla, we can see that the horizontal bands, or zonal flows, have different temps. (Jupiter is characterized by bands that alternately have rotational momentum in opposite directions.) The JWST/Geckzilla image shows cold temps at the poles and interestingly, the Great Red Spot [GRS] is cold at the depth to which the IR rays penetrate.

Additional temp data for the GRS comes from Juno's Microwave Radiometer, which penetrates to about 350 km. Here is a slide from a presentation at the 2019 AGU Fall Meeting which shows a range of temps with depth - and even a range of temps within the same depth. In this case, with microwave EM as imaged by Galanti et.al., darker colors indicate cooler temps and lighter colors indicate warmer temps. Note that at 0 km, the temp is mostly cooler. At 50 km, it is mostly warmer. At 350 km, about 25% to 33% of the depth range is cooler with the remaining 66% to 75% being warmer.

VictorBorun asked:
Why evening clouds gap, 670 km at the equator?
Why bright polar cups?
It seems to me that the gap that is noted on the right side of the image is due to IR waves passing through the dust and gases that are present so that they are not being scattered/reflected or absorbed. The gap probably does not exist in visible light.

The reason for the bright polar caps and bright GRS, according to the model I submit in my published poster at AGU Fall Meeting 2020, https://agu2020fallmeeting-agu.iposters ... 5-8F-8C-6A is that Jupiter has gaseous debris on top of an ice shell. Gases on a rotating body accumulate at the equator, and are sparse at the poles. Evidently, the gases and other debris are about 3750 km thick at the equator; because, T. Guillot et. al. report in a paper that the gravity data from Juno reveals rigid-body rotation under 3500 km - 3750 km of equatorial gases. Guillot, T., Miguel, Y., Militzer, B. et al. A suppression of differential rotation in Jupiter’s deep interior. Nature 555, 227–230 (2018). https://doi.org/10.1038/nature25775. (To be clear the authors of the paper attribute the rigid-body rotation to electromagnetic effects, NOT an ice layer.)

My research uses UV data from Juno to reveal that Jupiter's poles exhibit complete absorption of UV in a characteristic wavelength range for UV absorption by ice in space (vacuum UV [VUV]). Brightness for water ice in space goes to zero for VUV at 165 nm to 180 nm. I show this in the 6th evidence section in the "Evidence from Juno, Cassini and Other" part of my poster. This is true for UV brightness readings from latitudes +90 deg to -74.5 deg and -90 deg to -74.5 deg. I found it to be true even in the area of the auroras.

A UV loss cone was reported by Allegrini et. al. 2020, "Energy flux and characteristic energy of electrons over Jupiter's main auroral emission." Journal of Geophysical Research; Space Physics, 125, e2019JA027693. The Allegrini team was focused on the aurora activity and did not track UV at specific wavelengths. I believe that this is why they did not see the UV loss at wavelengths 165 nm to 180 nm in the regions of the aurorae.

Jupiter's temperature story involves heat due to friction with the differential flows of debris on top of the ice shell. This heat maintains a thin water layer between the ice shell and the outer swirling debris... according to the model I assert.

To be clear, the trusted professors of space science do not even entertain the idea that Jupiter could have an ice shell. Even though Scott Bolton, the lead investigator of the Juno mission said that Jupiter is a whole new planet from what we thought, the team is still, for the most part, using the same models that they were prior to Juno's insertion into its planetary orbits.

Anyway, I thought that some of my fellow Asterisk participants might be interested in some of this info, Please forgive me if I have stepped out of bounds to bring up a nonstandard interpretation of data observations.

I sign off with my favorite image of Jupiter in infrared light, from the far side of Jupiter.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Thu Jul 28, 2022 6:24 pm

There are four wheels, two each for the long wavelength channel and the short wavelength channel (which have different optical paths). They are often used in combination. For instance, when the F323N filter (long wavelength pupil wheel) is used, it is typically paired with the F322W2 filter (long wavelength filter wheel) for blocking purposes.

This image was constructed from two data channels, one imaged through the F323N/F322W2 pair, and the other through the F212N filter (short wavelength filter wheel).

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by VictorBorun » Thu Jul 28, 2022 6:01 pm

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Mel » Sun Jul 24, 2022 7:14 pm

Sorry. The Fits-header shows filter: F322W2 and pupil: F323N. I think both were used.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Mel » Sun Jul 24, 2022 7:11 pm

Ok, I did an extra check.
The NIRCam Filters are listed here: https://jwst-docs.stsci.edu/jwst-near-i ... am-filters

F322W2 is an extra-wide filter, covering the 2.4-4.0 Micron range and the F212N has H2 (hydrogen) listed as "use". The list does not include NH3, so I think it is still possible that F212N covers NH3.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Mel » Sun Jul 24, 2022 6:36 pm

VictorBorun wrote: Wed Jul 20, 2022 4:37 am Europa must be easier to warm in the sun than Jupiter

A second Metis? Adrastea?
Why evening clouds gap, 670 km at the equator?
Why bright polar cups?
Metis.jpg
Yes, I think it is Adrastea. It moves once you align the images that were taken at different times and appears in both filters.
First image start time: 2022-06-28 01:50:28
Second image start time: 2022-06-28 02:10:49
https://media.giphy.com/media/rGphGWET9 ... /giphy.gif

Image noise created by the telescope only appears in one filter (blue blob in the lower right, moving in the zoomed-out gif). Something like a lens flare caused by the bright Jupiter.
https://media.giphy.com/media/lwLRGuOZW ... /giphy.gif

---

Response to comments about the colors:
Filters are F322W2 (colored in red) and F212N (colored in blue). I can't tell you much about the F322W2 filter, but here is my interpretation of F212N:

I suspect the F212N filter (N="narrow" at wavelength=2.12 Micron) does cover an absorption line. The F212N could be located over an ammonia (NH3) absorption band.
Source: Figure 3 top of https://ui.adsabs.harvard.edu/abs/2022A ... M/abstract. A paper about Y-dwarfs, basically free-floating jupiter-temperature planets. Logarythmic x-axis in the figure, so I had problems to interpret where the absoption bands appear.

But in general: If you see a one-filter image of Jupiter and the Great-Red-Spot (GRS) is unusually bright, then you can assume at it is a molecular feature with a narrow filter.

Example with ESO VLT MUSE:
Observation: http://archive.eso.org/dataset/ADP.2019 ... :26:39.587
File size ~3GB
Software: QFitsView
Feature: H2O (water-vapor) between 0.88 and 0.9 Micron (x-axis bottom graph: 8800 to 9000 Angstrom)
Left I show an image outside the absorption-band and on the right I show an image inside the absorption-band, which appears as this deep valley in the spectrum (bottom). See the similarities between the H2O VLT MUSE image and the JWST image: GRS and the band at the equator appear bright.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Ann » Thu Jul 21, 2022 5:03 am

Chris Peterson wrote: Wed Jul 20, 2022 1:04 pm
Ann wrote: Wed Jul 20, 2022 5:38 am
RocketRon wrote: Wed Jul 20, 2022 5:29 am The colouring process is not yet well explained (?) for Webb infrared images, but bright white is colder ?
Thus the poles ?
And, it seems, the Great Red Spot ...
I think whiter means warmer in this image.

Ann
Again, this is why we generally need to look at the individual images to more fully understand what's going on. These are narrowband images, which are usually made to isolate emission bands. If the light is coming from such emissions, then we can't understand it in terms of temperature. But if the light is a slice of continuum glow, then we can look at the 2.12 um data where the peak temperature is 1400 K, and the 3.23 um data where the peak temperature is 900 K, and learn at least something about relative temperatures.
Exactly so, of course, Chris.

And it seems I was wrong about whiter being warmer on Jupiter. The opposite would appear to be true.

23_candy_7[1].png
Jupiter's south tropical zone observed by the Juno spacecraft, May 19, 2017.
The small white clouds are composed of water and ammonia ice
and form towers 50 km (30 miles) wide and 50 km high.
Image: NASA/SWRI/MSSS/Gerald Eichstadt/Sean Doran
Britannica wrote:

Jupiter’s clouds are formed at different altitudes in the planet’s atmosphere. Except for the top of the Great Red Spot, the white clouds are the highest, with cloud-top temperatures of about 120 kelvins (K; −240 °F, or −150 °C).
...
The tawny clouds that are widely distributed over the planet occur at lower levels. They appear to form at a temperature of about 200 K (−100 °F, −70 °C)
...
Sulfur compounds have also been proposed to explain the dark brown coloration of the ammonia clouds detected at still lower levels, where the measured temperature is 260 K (8 °F, −13 °C).
...
Dark regions occur near the heads of white plume clouds near the planet’s equator, where temperatures as high as 300 K (80 °F, 27 °C) have been measured.
What about the Great Red Spot?

N2ShUzQRtFuvTP8iqrbgrj-1200-80[1].png
This illustration shows how a combination of gravity and acoustic waves
transfers heat above the Great Red Spot to Jupiter's upper atmosphere.
(Image credit: Art by Karen Teramura, UH IfA, James O'Donoghue)
Space.com wrote:

Jupiter's Great Red Spot is apparently also red hot: The highest temperatures ever observed on the planet were recently detected in the region above the ginormous storm.

The Great Red Spot (GRS) is a massive storm about twice the diameter of Earth that lies in lowest layer of Jupiter's atmosphere. About 497 miles (800 kilometers) above this humongous storm, astronomers measured temperatures reaching about 700 degrees Fahrenheit (about 370 degrees Celsius) higher than normal, James O'Donoghue, lead author of the new study and a research scientist with Boston University's (BU) Center for Space Physics, told Space.com.

Generally, atmospheric temperatures on Jupiter are around 1,700 degrees F (around 930 degrees C), with the exception of areas above the planet's poles, which are heated by auroras. Above the Great Red Spot, however, the atmosphere is about 2,420 degrees F (about 1,330 degrees C), O'Donoghue said.

Previous heat-distribution models suggested that Jupiter's atmosphere should be much cooler, largely because the planet is about fives time further from the sun than Earth is. So, having ruled out solar heating from above, the authors of the new research found evidence suggesting this atmospheric heating is largely driven by a combination of gravity waves and acoustic waves generated by turbulences in the atmosphere below the Great Red Spot.

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by VictorBorun » Thu Jul 21, 2022 4:49 am

Avalon wrote: Thu Jul 21, 2022 2:40 am Could the "cloud separation" on the right limb also be an artifact?
If it is than neither optic (like 8 spikes of Europa) nor sensor array leaks along columns and rows.
A double exposition? Some kick has shifted NIRICam's sensor? It could not look like this, neither

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Avalon » Thu Jul 21, 2022 2:40 am

Could the "cloud separation" on the right limb also be an artifact?

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Sa Ji Tario » Wed Jul 20, 2022 3:29 pm

Aweßome!!!

Re: APOD: Jupiter and Ring in Infrared from Webb (2022 Jul 20)

by Chris Peterson » Wed Jul 20, 2022 1:04 pm

Ann wrote: Wed Jul 20, 2022 5:38 am
RocketRon wrote: Wed Jul 20, 2022 5:29 am The colouring process is not yet well explained (?) for Webb infrared images, but bright white is colder ?
Thus the poles ?
And, it seems, the Great Red Spot ...
I think whiter means warmer in this image.

Ann
Again, this is why we generally need to look at the individual images to more fully understand what's going on. These are narrowband images, which are usually made to isolate emission bands. If the light is coming from such emissions, then we can't understand it in terms of temperature. But if the light is a slice of continuum glow, then we can look at the 2.12 um data where the peak temperature is 1400 K, and the 3.23 um data where the peak temperature is 900 K, and learn at least something about relative temperatures.

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