Credits: International Gemini Observatory/NOIRLab/NSF/AURA/NASA/ESA, M.H. Wong and I. de Pater (UC Berkeley) et al.
Credits: JunoCam Image data: NASA/JPL-Caltech/SwRI/MSSS; JunoCam Image processing by Kevin M. Gill (CC BY); Earth Image: NASA
New findings from NASA’s Juno probe orbiting Jupiter provide a fuller picture of how the planet’s distinctive and colorful atmospheric features offer clues about the unseen processes below its clouds. The results highlight the inner workings of the belts and zones of clouds encircling Jupiter, as well as its polar cyclones and even the Great Red Spot.
Researchers published several papers on Juno’s atmospheric discoveries today in the journal Science and the Journal of Geophysical Research: Planets. Additional papers appeared in two recent issues of Geophysical Research Letters.
“These new observations from Juno open up a treasure chest of new information about Jupiter’s enigmatic observable features,” said Lori Glaze, director of NASA’s Planetary Science Division at the agency’s headquarters in Washington. “Each paper sheds light on different aspects of the planet’s atmospheric processes – a wonderful example of how our internationally-diverse science teams strengthen understanding of our solar system.”
Juno entered Jupiter’s orbit in 2016. During each of the spacecraft’s 37 passes of the planet to date, a specialized suite of instruments has peered below its turbulent cloud deck.
“Previously, Juno surprised us with hints that phenomena in Jupiter’s atmosphere went deeper than expected,” said Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio and lead author of the Journal Science paper on the depth of Jupiter’s vortices. “Now, we’re starting to put all these individual pieces together and getting our first real understanding of how Jupiter’s beautiful and violent atmosphere works – in 3D.”
Juno’s microwave radiometer (MWR) allows mission scientists to peer beneath Jupiter’s cloud tops and probe the structure of its numerous vortex storms. The most famous of these storms is the iconic anticyclone known as the Great Red Spot. Wider than Earth, this crimson vortex has intrigued scientists since its discovery almost two centuries ago.
The new results show that the cyclones are warmer on top, with lower atmospheric densities, while they are colder at the bottom, with higher densities. Anticyclones, which rotate in the opposite direction, are colder at the top but warmer at the bottom.
The findings also indicate these storms are far taller than expected, with some extending 60 miles (100 kilometers) below the cloud tops and others, including the Great Red Spot, extending over 200 miles (350 kilometers). This surprise discovery demonstrates that the vortices cover regions beyond those where water condenses and clouds form, below the depth where sunlight warms the atmosphere.
The height and size of the Great Red Spot means the concentration of atmospheric mass within the storm potentially could be detectable by instruments studying Jupiter’s gravity field. Two close Juno flybys over Jupiter’s most famous spot provided the opportunity to search for the storm’s gravity signature and complement the MWR results on its depth.
With Juno traveling low over Jupiter’s cloud deck at about 130,000 mph (209,000 kph) Juno scientists were able to measure velocity changes as small 0.01 millimeter per second using a NASA’s Deep Space Network tracking antenna, from a distance of more than 400 million miles (650 million kilometers). This enabled the team to constrain the depth of the Great Red Spot to about 300 miles (500 kilometers) below the cloud tops.
“The precision required to get the Great Red Spot’s gravity during the July 2019 flyby is staggering,” said Marzia Parisi, a Juno scientist from NASA’s Jet Propulsion Laboratory in Southern California and lead author of a paper in the Journal Science on gravity overflights of the Great Red Spot. “Being able to complement MWR’s finding on the depth gives us great confidence that future gravity experiments at Jupiter will yield equally intriguing results.”
Belts and Zones
In addition to cyclones and anticyclones, Jupiter is known for its distinctive belts and zones – white and reddish bands of clouds that wrap around the planet. Strong east-west winds moving in opposite directions separate the bands. Juno previously discovered that these winds, or jet streams, reach depths of about 2,000 miles (roughly 3,200 kilometers). Researchers are still trying to solve the mystery of how the jet streams form. Data collected by Juno’s MWR during multiple passes reveal one possible clue: that the atmosphere’s ammonia gas travels up and down in remarkable alignment with the observed jet streams.
“By following the ammonia, we found circulation cells in both the north and south hemispheres that are similar in nature to ‘Ferrel cells,’ which control much of our climate here on Earth”, said Keren Duer, a graduate student from the Weizmann Institute of Science in Israel and lead author of the Journal Science paper on Ferrel-like cells on Jupiter. “While Earth has one Ferrel cell per hemisphere, Jupiter has eight – each at least 30 times larger.”
Juno’s MWR data also shows that the belts and zones undergo a transition around 40 miles (65 kilometers) beneath Jupiter’s water clouds. At shallow depths, Jupiter’s belts are brighter in microwave light than the neighboring zones. But at deeper levels, below the water clouds, the opposite is true – which reveals a similarity to our oceans.
“We are calling this level the ‘Jovicline’ in analogy to a transitional layer seen in Earth’s oceans, known as the thermocline – where seawater transitions sharply from being relative warm to relative cold,” said Leigh Fletcher, a Juno participating scientist from the University of Leicester in the United Kingdom and lead author of the paper in the Journal of Geophysical Research: Planets highlighting Juno’s microwave observations of Jupiter’s temperate belts and zones.
Polar Cyclones
Juno previously discovered polygonal arrangements of giant cyclonic storms at both of Jupiter’s poles – eight arranged in an octagonal pattern in the north and five arranged in a pentagonal pattern in the south. Now, five years later, mission scientists using observations by the spacecraft’s Jovian Infrared Auroral Mapper (JIRAM) have determined these atmospheric phenomena are extremely resilient, remaining in the same location.
“Jupiter’s cyclones affect each other’s motion, causing them to oscillate about an equilibrium position,” said Alessandro Mura, a Juno co-investigator at the National Institute for Astrophysics in Rome and lead author of a recent paper in Geophysical Research Letters on oscillations and stability in Jupiter’s polar cyclones. “The behavior of these slow oscillations suggests that they have deep roots.”
JIRAM data also indicates that, like hurricanes on Earth, these cyclones want to move poleward, but cyclones located at the center of each pole push them back. This balance explains where the cyclones reside and the different numbers at each pole.
More About the Mission
JPL, a division of Caltech in Pasadena, California, manages the Juno mission. Juno is part of NASA’s New Frontiers Program, which is managed at NASA’s Marshall Space Flight Center in Huntsville, Alabama, for the agency’s Science Mission Directorate in Washington. Lockheed Martin Space in Denver built and operates the spacecraft.
Follow the mission on Facebook and Twitter, and get more information about Juno online at:
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The stated precision of 0.01 millimeter per second while Juno is moving 209,000 kilometers per hour is amazing. I think there should be a manned Jupiter “surface” landing, which some think is impossible due to the gas atmosphere transitioning to liquid planet, and I’m sure William Shatner, who has recovered from his last space trip, will volunteer to fly there and let us know for sure.
Brother Shatner’s reported weight is 187 lb. On Jupiter he would weigh 448 lb. This could be a problem….
“… First 3d View of Jupiter Atmsphere.”
I do not think the lead image above is 3D. It is a composite IR/Visible light image. The IR part (on left) is similar to terrestrial satellite IR images, where the darker areas correspond to thicker cloud depth above the “surface” layer. As on Earth, the thickness of the underlying clouds can be estimated from the amount of IR attenuation.
I believe that was this thickness estimation that led Principal Investigator Bolton (who was interviewed for the article) to say “Now, we’re starting to put all these individual pieces together and getting our first real understanding of how Jupiter’s beautiful and violent atmosphere works — in 3D.” No mention of 3D imaging here.
Yes, a 3D image could be rendered from “shade-to-shape” analysis, as is commonly done in computer vision. Perhaps they have done this, but I see no evidence of this kind of 3d rendering in this image. It looks flat.
Jupiter’s atmosphere appears much like Earth’s circulation systems. The various bands match up fairly well with Earth’s latitudinal variation.Hadley cells, Ferrel cells and polar cells.
Columbus relied upon the trade winds to reach “Asia”, and the westerlies to get back to Europe. He had experienced the latter in the Azores. His crew didn’t know about them, thus became mutinous due to fear of not being able to return home, so steady were the easterly trades.
Absolutely right, as described by myself and Philip Mulholland in relation to Earth, Titan and Venus.
Cool!
But surely only warming worlds have extreme weather?
I believe Jupiter has a surface temperature of ~-145C
The storm known as the great red spot has been raging for centuries.
Can Mann explain that?
In general, the colder a planet, the faster its winds. Venus might be an exception.
I know that, maybe I should have added a </sarc>
The Venus winds have to be faster to get potential energy back to the surface fast enough to match radiation out with radiation in.
Distance from the sun plus density of atmosphere determine the speeds required.
Being much further away from the sun and having a bigger but less dense atmosphere it appears that Jupiter can afford to have less powerful winds.
However, we may find that Jupiter’s winds are stronger lower down where density is greater whereas Venus’s winds are stronger higher up where insolatiion is more powerful.
Every planet with an atmosphere must arrive at a balance between density, insolation and windspeed for the atmosphere to be retained.
Mars has a very thin atmosphere with periods of little convection but periodically the balance is restored by times of planetwide dust storms involving enhanced convective overturning and faster winds.
If Mars were to gain atmospheric mass then the atmosphere would stabilise into a more persistent pattern of convective overturning.
Apparently he can’t even explain his own graphs. That’s the real explanation of why he won’t reveal his data.
I’m sorry to add this, but those photos make me think of nice, crispy bacon, fresh out of the frying pan. I am hopeless, I know, but now I need to buy more bacon and freeze it for the hard times ahead. (Sigh.)
On another note, I have frequently wondered what the solar system might be like if Jupiter weren’t in its particular orbit. Is Old Jove the “balancer” or the planet that keeps things in some sort of order? Would the inner planets go wandering off on their own without Jupiter’s influence?
Actually, I enjoyed this article quite a bit, even though the photos make me think of bacon….
By Jove! 🙂
That is very impressive.
Yes indeed. It’s also amazing the level of detail they can get from ground based telescopes these days (Gemini North).
‘The new results show that the cyclones are warmer on top, with lower atmospheric densities, while they are colder at the bottom, with higher densities. Anticyclones, which rotate in the opposite direction, are colder at the top but warmer at the bottom.’
Which is precisely what one would expect from the work of myself and Philip Mulholland previously published here and elsewhere.
The same applies for Earth and every other body with a convecting atmosphere.
The reason being that:
Rising air within cyclones cools the surface to below the anticipated S-B temperature and falling air within anticyclones warms the surface above the anticipated S-B temperature.
It is the relatively slow process of creation of potential energy within rising air and the reconversion to kinetic energy within falling air that causes a delay in radiative loss to space and thereby causes the surface temperature enhancement.
If radiative gases seek to intervene then all that happens is a change in the speed of convective overturning which neutralises any thermal effect from radiative material within an atmosphere.
My Comment: Not “crimson;” in fact barely tinged red.
Very interesting article!
From the article: “By following the ammonia, we found circulation cells in both the north and south hemispheres that are similar in nature to ‘Ferrel cells,’ which control much of our climate here on Earth”, said Keren Duer, a graduate student from the Weizmann Institute of Science in Israel and lead author of the Journal Science paper on Ferrel-like cells on Jupiter. “While Earth has one Ferrel cell per hemisphere, Jupiter has eight – each at least 30 times larger.”
On the Earth we have the Hadley circulation which begins at the equator and reaches the midlatitudes, and then comes the Ferrel circulation, which circulates the air in the opposite direction as the Hadley circulation, and then we have the polar circulation at higher latitudes.
So, I’m confused. How can Jupiter have eight Ferrel circulations, and where do the Hadley circulation and the polar circulation fit in to this scenario? I’m not saying Jupiter does not have eight Ferrel cells, I’m asking how all these circulation patterns would line up with each other.
I like that visual comparison of the Great Red Spot with the Earth. It puts things in perspective.
Also, can we compare the patterns of the polar vortex on Earth with the pattern on Jupiter? Earth’s atmosphere is not so deep, but do we have persistent patterns in the same way Jupiter does?