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

[APOD Robot]

Jupiter and Ring in Infrared from Webb

Explanation: Why does Jupiter have rings? Jupiter's main ring was discovered in 1979 by NASA's passing Voyager 1 spacecraft, but its origin was then a mystery. Data from NASA's Galileo spacecraft that orbited Jupiter from 1995 to 2003, however, confirmed the hypothesis that this ring was created by meteoroid impacts on small nearby moons. As a small meteoroid strikes tiny Metis, for example, it will bore into the moon, vaporize, and explode dirt and dust off into a Jovian orbit. The featured image of Jupiter in infrared light by the James Webb Space Telescope shows not only Jupiter and its clouds, but this ring as well. Also visible is Jupiter's Great Red Spot (GRS) -- in comparatively light color on the right, Jupiter's large moon Europa -- in the center of diffraction spikes on the left, and Europa's shadow -- next to the GRS. Several features in the image are not yet well understood, including the seemingly separated cloud layer on Jupiter's right limb.

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[VictorBorun]

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?

[RocketRon]

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 ...

[Ann]

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

[geckzilla]

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 can only explain that they are both H2 filters, just at different wavelengths and that the "red" one is much more nondescript, and featured more heavily at the poles. There is an aurora sticking out of the south pole.

[AVAO]

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

APOD 2020 May 13: Jupiter in Infrared from Gemini

https://apod.nasa.gov/apod/ap200513.html
Image Credit: International Gemini Observatory, NOIRLab, NSF, AURA; M. H. Wong (UC Berkeley) & Team;
Acknowledgment: Mahdi Zamani; Text: Alex R. Howe (NASA/USRA, Reader's History of SciFi Podcast)

"Infrared light can pass through clouds better than visible light, allowing us to see deeper, hotter layers of Jupiter's atmosphere, while the thickest clouds appear dark."

With Gemini, the equator band, which is white in visible light, is dark with Gemini in the IR, and bright again with WBB in the IR. I can't understand that?


Jupiter Poles: Hot from Solar Wind


Instrument: Subaru Telescope Credit: NAOJ/NASA/JPL-Caltech

https://www.jpl.nasa.gov/images/pia2277 ... solar-wind
https://www.nature.com/articles/s41586-021-03706-w

Is this explanation plausible for the hot poles of Jupiter?
If yes. Why aren't the poles of the earth hot too?

[madtom1999]

Jupiter is a gas planet, Earth has an atmosphere. During aurora the top of the atmosphere is ionised and radiates - but not enough to affect the ground underneath noticeably in earth's case.

[JohnD]

That the Great Red Spot is hotter than anything else on Jupiter might be expected - it's a welling up from deeper layers. But why are the Poles hotter?
John

[AVAO]

....That the Great Red Spot is hotter than anything else on Jupiter might be expected - it's a welling up from deeper layers. ...

Credit: International Gemini Observatory/NOIRLab/NSF/AURA

Comment to the picture: " In the image warmer areas appear bright, including four large hot spots that appear in a row just north of the equator. South of the equator, the oval-shaped and cloud-covered Great Red Spot appears dark."

https://noirlab.edu/public/images/noirlab2116a/

[rstevenson]

Today’s APOD has a gauzy curtain of white over it. What is that? Presumably an image artifact, but I haven’t seen it in other JWST images.

Rob

[Locutus76]

That the Great Red Spot is hotter than anything else on Jupiter might be expected - it's a welling up from deeper layers. But why are the Poles hotter?
John

I’m just guessing, but maybe Jupiter’s much stronger magnetic fields create more friction between particles near the poles, and thus more heat?

[VictorBorun]

Today’s APOD has a gauzy curtain of white over it. What is that? Presumably an image artifact, but I haven’t seen it in other JWST images.

Rob

it was even worse in the 2 frames used for the posted image, 2.12 and 3.23 μm

After some processing they got better:

[orin stepanek]

A good view of Jupiter's ring!

People just don't under kitty!

[JohnD]

....That the Great Red Spot is hotter than anything else on Jupiter might be expected - it's a welling up from deeper layers. ...

Comment to the picture: " In the image warmer areas appear bright, including four large hot spots that appear in a row just north of the equator. South of the equator, the oval-shaped and cloud-covered Great Red Spot appears dark."

https://noirlab.edu/public/images/noirlab2116a/

That is very confusing! Do the Webb and the camera used in the Noirlab (?) picture use different infrared wavelengths?

[sc02492]

From what I understand, JWST's main goal in taking these images was not to image Jupiter per se, but to show that the telescope can resolve faint structures like the ring system, which would suggest that it could also reveal equally faint structures like plumes of water extending from moons like Europa, as well as track fast moving objects like asteroids without being obscured by bright object like a planet. That to me is the most remarkable potential of JWST for doing planetary science- a space telescope in orbit at L2 capable of resolving such structures, as opposed to requiring a dedicated mission like Galileo or Cassini to actually travel there. The following link provides greater insight: https://www.universetoday.com/156738/jw ... its-moons/ .

Steve

Steve Cannistra
www.starrywonders.com

[rstevenson]

Today’s APOD has a gauzy curtain of white over it. What is that? Presumably an image artifact, but I haven’t seen it in other JWST images.

Rob

it was even worse in the 2 frames used for the posted image, 2.12 and 3.23 μm

After some processing they got better:

So the gauze curtain we see is glare which can be processed out to yield a nice dark space background. But in order to see the very faint ring structure they had to leave in some of the glare. Makes perfect sense. Thanks Victor.

Rob

[johnnydeep]

What are these "things" I've indicated? :

1 - moon?
2 - moon?
3 - a...ring?
4 - another moon shadow?

[Chris Peterson]

Today’s APOD has a gauzy curtain of white over it. What is that? Presumably an image artifact, but I haven’t seen it in other JWST images.

Rob

it was even worse in the 2 frames used for the posted image, 2.12 and 3.23 μm

After some processing they got better:

So the gauze curtain we see is glare which can be processed out to yield a nice dark space background. But in order to see the very faint ring structure they had to leave in some of the glare. Makes perfect sense. Thanks Victor.

Rob

I'm not sure it's glare. I'd expect that to be symmetrical. This looks more like some kind of readout artifact, akin to blooming, given its alignment with the rows and columns of the sensor.

[Chris Peterson]

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.

[Sa Ji Tario]

Aweßome!!!

[Avalon]

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

[VictorBorun]

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

[Ann]

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.

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?

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.

[Mel]

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).

Click to view full size image

See the similarities between the H2O VLT MUSE image and the JWST image: GRS and the band at the equator appear bright.

[Mel]

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.