Astronomy

What is germane doing in the atmosphere of Jupiter?

What is germane doing in the atmosphere of Jupiter?

Germane (GeH4) has been detected in the atmosphere Jupiter.

Its formation from the elements seems to be thermodynamically unfavorable because its enthalpy of formation is positive and (I think) it has lower entropy than the free elements.

So what the heck is it doing there, considering free germanium would sink and free hydrogen would float?


How much specific elements sink inside a planetary caldron with variations of heat and thermals and chemistry, depends not just on their density but also the element's chemistry. This question discusses Uranium in Earth's core and the top answer suggests (I believe correctly) there's essentially no Uranium in Earth's core, it's largely in the crust because Uranium readily oxidizes, so it forms lighter elements that don't sink but rise with the silicates and basalt, which is (roughly) similar density. Uranium floats in the Earth's mantle because it binds with Oxygen.

Free Oxygen (O2) should destroy any Germane, but there's likely so little free Oxygen in Jupiter's atmosphere that the Germane is able to be present (in a fraction of parts per billion - it's very rare in Jupiter, but it's detectable).

Also, given Jupiter's internal heat, thermodynamically unfavorable doesn't matter much. There's enough heat that chemistry tends to operate more in an equilibrium balance, and not always in the exothermic direction, like we usually see in most natural reactions at temperatures we see on Earth.

Finally, and at risk of stating the obvious, Germane is one of those "weird" heavy gases, due to the atomic electrical symmetry, and because it's a gas, not a solid and given Jupiter's significant thermal currents, it mixes in Jupiter's atmosphere. It likely freezes out of Jupiter's upper atmosphere when it gets too cold, but it's present in the lower atmosphere, present enough to be detected anyway. (I think it's less than 1 ppb). - That's a brief answer anyway. I've not read any of the recent articles on this. They're all pay articles. I invite anyone who has read them to give a more detailed answer.

Edit

So what the heck is it doing there, considering free germanium would sink and free hydrogen would float?

I want to add that gases behave differently than solids or liquids. In chemistry, sometimes things mix and form solutions (like water and alcohol), sometimes they don't and for layers (like oil and water).

Gases are particularly good at staying mixed and not layering, especially where wind and updrafts are present.

why aren't scads of other simple components mentioned in discussions of Jupiter's atmosphere, like methylamine

There is Methylamine in Jupiter's atmosphere. Saturn's too. This research study mentions "bands" of it. This one also discusses it.

urea, and oxamic acid, to name just a few?

Urea is a solid at room temperature. It decomposes when melted so it's not stable as a gas. It melts at 133-135 C. It might never be stable on Jupiter as a gas since it's not even stable as a liquid above 135 C.

Oxamic Acid, isn't even stable by itself, it's water soluble. It's also Oxygen abundant, and free Oxygen is rare on Jupiter.

So those last 2 aren't good examples, neither is a stable as a gas at all, Germane is stable in Jupiter's atmosphere, though it's present in very small quantities.

An important point to consider with trace gases in planetary atmospheres is formation and half life. Methane, for example isn't stable in Earth's atmosphere. It reacts with Oxygen, though at a few hundred parts per billion, it's rare enough that it doesn't react a lot. Methane is also constantly being produced in the stomachs of mammals (gas) but it also gets destroyed, reacting with oxygen whenever it gets near a flame or lightning, combining with Oxygen to form CO2 and Water. It has a half life of about 10-15 years, but because it's constantly being created by incomplete digestion and decomposition, it's always present in our atmosphere - in about 1 part per million.

CO2 has a longer half life in our atmosphere, mostly it isn't destroyed, it needs to be rained out. It's also constantly being resperated, destroyed in photosynthesis and re-created by respiration.

Point of all this is that any trace element in a planet's atmosphere, must have a source of creation and a half life of, destruction if you will.

A curious exception on Earth is Argon. Argon is a byproduct of radioactive decay and as a noble gas, it doesn't react with anything, so it gets created and it just stays in our atmosphere. It gets created slowly but because it's never destroyed, it's currently about 1% of our atmosphere.

GeH4 follows the same basic guideline. It gets created inside Jupiter and it's stable enough in Jupiter's atmosphere that it's equilibrium between creation and destruction leads to about 1 part per billion. I don't know nearly enough to say what it's atmospheric half life is.

As you said, there are "scads" of elements in Jupiter's atmosphere. There re countless more that are NOT in it's atmosphere. For an element to be present in an atmosphere it needs some degree of stability and some form of creation.

Jupiter is nearly 90% hydrogen. It's not practical for it's hydrogen to float around the heavier elements. Think of it as a sea of hydrogen, with other stuff in the hydrogen, some mixes and floats, some sinks, some chemically reacts, but the hydrogen is always present.

Anyway, I only meant to touch on some of the basics and not give so long an answer.

I mean literally, how did you figure it out? What did you google? I ask because I'm dealing with hundreds of compounds and I'm hoping you found a nice centralized location for information like that.

We're getting a little outside the guidelines here, but briefly, I looked up the molecular structure of each of the compounds you suggested and they didn't look like gases to me. They looked too complex and crooked shaped, so I was suspicious from the get go.

But the answer to your question is simply that I checked Wikipedia, which can be long (Urea) or very short (Oxalic acid), and not always 100% reliable. Once there I did a word search for "boiling point" and "Melting point" when boiling point didn't show up. For any molecule to be a gas it needs a boiling point, so that's the first quick and easy thing to search.

You can also look for phase diagrams, which are great, but rare for anything but the most common molecules.

For Oxalic acid, I was wrong, it is a solid. Wikipedia only mentioned it in an aqueous solution. This site gives it a melting point but no boiling point, which suggests to me, it doesn't make it as a gas, or, at least, not easily. Maybe under very specialized circumstances, perhaps in a pressure tank filled with noble gases, but I'm just speculating.

Googling "Melting point" "boiling point", next to the name of the element isn't briliant, but it can provide a quick answer.


Longer addition:

Gases tend to be smaller molecules, noble gases or when more massive, they need to be symmetric. A chemist probably wouldn't put it that way, but that's the gist of it.

Take line 2 of the periodic table, Lithium (number 3) to Florine (number 9) - ignoring noble gases for now. These atoms have 4 electron pair orbitals in their outer shell which want to form a tetrahedron. CO2 has 2 double bonds - making it a straight line, or non-polar is the chemistry term. I used the word symmetrical in my initial answer. Non-polar is, I think, more correct.

That non-polarity or symmetry is why CO2 doesn't bond easily with other things, because it's a straight line, with equal charges on each end. because it doesn't bond easily with other molecules, it's a gas at relatively low temperature. CH4, while a tetrahedral, not a line, is also non-polar and has an equal charge on all sides, so it also remains a gas at quite cold temperatures.

Water (H20) is different. Oxygen shares 2 single bonds or pairs of electrons with Hydrogen, it fills it's other 2 outer electron pairs itself, so it's bent shape and it's polar. This polarity gives H20 a side with a positive charge and a side with a negative charge. That polarity helps it bond with itself. That's why water stays wet or stays ice in much warmer temperature than similar mass molecules like CH4 and heavier molecules like CO2.

For a gas, non-polarity helps. A straight or tetrahedral, or flat triangle or six sided polyhedral (kind of a cube shape) and a few carbon chains are, as far as I know, the only options for non-polarity. Very light, polar molecules can be gas molecules too. All this varies somewhat with temperature and pressure, so there's no exact answers.

Common gases at room temperature. - note, this is not a complete list.

I'll resort them and add a few.

Elemental gases

H2 (hydrogen) 2.02 N2 (nitrogen) 28.01
O2 (oxygen) 32.00
F2 (fluorine) 38.00
Cl2 (chlorine) 70.91
BR2 (bromine) - at about 60 degrees C. I2 (Iodine) - at about 180 degrees C. AT2 (Astatine) - at about 337 degrees C.

It's worth noting that all of these, with the exception of Hydrogen and Nitrogen, bond more readily with other elements and are unlikely to be present in a planetary atmosphere. (Photosynthesis creating O2 being an exception to this rule).

Noble gases

He (helium) 4.00
Ne (neon) 20.18
Ar (argon) 39.95
Kr (krypton) 83.80
Xe (xenon) 131.30
Radon (radioactive, short half life, but it is a gas)

These can be present in a planet's atmosphere as they are mostly chemically inactive. (Xenon is slightly reactive).

Gas molecules (non-polar)

CH4 (methane) 16.04
NH3 (ammonia) 17.03 C2H6 (ethane) 30.07
PH3 (phosphine) 34.00
CO2 (carbon dioxide) 44.01
C3H8 (propane) 44.10
C4H10 (butane) 58.12
BF3 (boron trifluoride) 67.80
SF6 (sulfur hexafluoride) 146.05

(I'll say more about these shortly).

Gas molecules, polar

HCN (hydrogen cyanide) 27.03
CO (carbon monoxide) 28.01
NO (nitrogen oxide) 30.01
H2S (hydrogen sulfide) 34.08
HCl (hydrogen chloride) 36.46
N2O (dinitrogen oxide) 44.01
NO2 (nitrogen dioxide) 46.01
O3 (ozone) 48.00
SO2 (sulfur dioxide) 64.06
CF2Cl2 (dichlorodifluoromethane) 120.91 (only a little polar) H20 (a gas under right temperature and pressure)

There are more polar molecules than non-polar, but outside of the somewhat odd CF2CL2, all polar gases are relatively light, SO2 being the most massive, molecular weight of 64.

You mentioned Methylamine which is basically ammonia (NH3) where one of the hydrogens is replaced by a methyl (CH3) group. NH2CH3.

DiMethylamine (CH3)2NH is also a gas at about 7 degrees C and up (boiling point).

Playing around with temperature and variations on the gas molecules (replacing H with CH3, replacing H with NH2, replacing H with OH, but remember, Oxygen tends to be spoken for, like a perfect 10 at a dance, so that's not a good one, unless there's life and a source of oxygen (photosynthesis).

Similarly the "Ane" series, more accurately called the Group 14 hydrides. Group 14: carbon, silicon, germanium, tin, and lead, and the hydrides, Methane, Silane, Germane, Stanane, Plumbane. All of these are polar and all are gas molecules. Most are very reactive with Oxygen. Methane requires a flame, but the other 4 react with Oxygen quite easily.

And as temperature goes up, you add new gases, but heat tends to destroy complex chemistry, so there's a bit of a trade-off. There's no easy answer as to what could be a gas and what couldn't, but starting with the building blocks and swaping might be a place to start. That doesn't always work though. CO2 is non polar and a gas. SO2, even though Silicon is in the carbon group, is polar and bent. It's not a gas (it's closer to sand) with a very high melting point.

So, the disappointing answer is, sometimes you can go down the column in the periodic table and find another and another gas simply by replacement and sometimes you can't. In the case of SIO2, the bonds are very different than CO2, and the melting point is over 3,000 degrees. Explained in detail in this question here.

Some of the Hexaflouride series is interesting. 4 of them are stable gases at Earth's temperature and generally non reactive enough to breath and sound like James Earl Jones when you talk, but they're not likely to be found in a planet's atmosphere cause they're vulnerable to photodisintigration and not likely to be reformed in significant numbers Other molecues are more likely to form.

And, ofcourse You could have a planet with a 3,000 degree surface temperature and all sorts of elemental gases, see cool periodic table with temperature slide) and at 6,000 degrees, all the elements are basically gases, but temperature that high, destroys any complex chemistry so you don't get complex molecules. Also, at temperatures that high, the exo/endo thermic direction no longer applicable. Molecules tend to form back and forth in an equilibrium ratio. That bit I remember from School.

On the Germane in Jupiter question, it does raise some other questions, what about the other Group 14 hydrides? What about Saturn? It's possible that Saturn has too little metallic hydrogen to create much Germane.

The trick in general is both formation and stability. If a gas has too short a half life (like if it's vulnerable to photodisintigration like a lot of carbon chains are), then it's not likely to last.

Jupiter also has storms and wind powerful enough to bring up some elements that aren't necessarily gas - like dust in a sense, up high into it's atmosphere, some carbon chains, sulfur and phosphorus and ammonium hydro-sulfide, (which, despite having a boiling point, it's more accurate to say it separates into Ammonia and Hydrogen Sulfide at 56.6 degrees C, in the cold upper clouds of Jupiter the two elements could combine, into something like a dust. Technically it's a salt. Source.

Apologies if I got carried away. I love thinking about planetary atmospheres. Can't wait till the J.W.S.T. gets a picture of some in other solar systems.

My kitten is trying to delete what I wrote, so I'll post it now - will tidy up later.


What is germane doing in the atmosphere of Jupiter? - Astronomy

All planets show a differentiation in their structure: Denser elements sink to the center of the planet and lighter elements "float" to the outer layers of a planet. Models of Jupiter show that it has a rocky core surrounded by an icy mixture of water and ammonia that is surrounded by hydrogen and helium.

Now comes my question: If gases like ammonia, methane, etc. are denser than hydrogen, why are they present in Jupiter's atmosphere? Shouldn't they have "sunk" a long time ago?

Your question is a good one. The basic reason that there are gases heavier than hydrogen in the upper part of Jupiter's atmosphere is that Jupiter is hot enough that the methane, ammonia, etc. in the atmosphere are gaseous (they don't condense to a liquid), and the atmosphere is well mixed by convection.

As Jupiter was accreting material during its formation, it grew hot enough that water and other molecules became gaseous and formed an envelope around the growing core. As time went on and more and more material fell onto the planet, the gaseous envelope became larger. Planetesimals that impacted the planet late in its formation had trouble penetrating through the surrounding envelope which was quite thick. The impactors sublimated in the atmosphere and added their heavy elements to the upper part of the planet. The heat caused convection which distributed the heavy elements uniformly through the envelope. They weren't able to sink into the core.

Another way to picture this is to think of Earth. We have N2 and O2 in our atmosphere, and yet we don't have a layer of N2 on the bottom and then a layer of O2. Atmospheric gasses don't separate out like this because they are constantly mixed by convection caused by thermal gradients.

Also, Saturn and Jupiter will still differentiate more over time. We think this is happening in Saturn right now. Saturn has cooled to a temperature where the helium becomes immiscible (unable to stay dissolved) in the liquid metallic hydrogen layer. The helium "rains" out onto the core, which releases energy. This process can explain the extra energy we see Saturn giving off, as well as the depletion of helium in the atmosphere that we observe. This same process should happen in Jupiter as it cools, but we think Jupiter is still too hot. (Although some astronomers believe that it has actually started recently, and this explains the slightly lower than expected helium abundance in Jupiter's atmosphere.)


What is Jupiter’s atmosphere like?

It’s not nice. Hydrogen and helium makes up most of Jupiter’s atmosphere along with traces of methane, ammonia, hydrogen sulfide and water. The clouds visible to optical telescopes are of ammonia ice, and it's those that create the planet's brown belts and white zones. It’s here that storms, often with lightning, take place–visible as bright plumes–that disrupt the equatorial belts, the effects of which can be visible for months or years. Those plumes behave much like the cumulonimbus clouds that precede thunderstorms on Earth.


ALMA Shows What’s Inside Jupiter’s Storms

Swirling clouds, big colorful belts, giant storms. The beautiful and incredibly turbulent atmosphere of Jupiter has been showcased many times. But what is going on below the clouds? What is causing the many storms and eruptions that we see on the ‘surface’ of the planet? However, to study this, visible light is not enough. We need to study Jupiter using radio waves.

New radio wave images made with the Atacama Large Millimeter/submillimeter Array (ALMA) provide a unique view of Jupiter’s atmosphere down to fifty kilometers below the planet’s visible (ammonia) cloud deck.

“ALMA enabled us to make a three-dimensional map of the distribution of ammonia gas below the clouds. And for the first time, we were able to study the atmosphere below the ammonia cloud layers after an energetic eruption on Jupiter,” said Imke de Pater of the University of California, Berkeley (EE. UU.).

The atmosphere of giant Jupiter is made out of mostly hydrogen and helium, together with trace gases of methane, ammonia, hydrosulfide, and water. The top-most cloud layer is made up of ammonia ice. Below that is a layer of solid ammonia hydrosulfide particles, and deeper still, around 80 kilometers below the upper cloud deck, there likely is a layer of liquid water. The upper clouds form the distinctive brown belts and white zones seen from Earth.

Many of the storms on Jupiter take place inside those belts. They can be compared to thunderstorms on Earth and are often associated with lightning events. Storms reveal themselves in visible light as small bright clouds, referred to as plumes. These plume eruptions can cause a major disruption of the belt, which can be visible for months or years.

The ALMA images were taken a few days after amateur astronomers observed an eruption in Jupiter’s South Equatorial Belt in January 2017. A small bright white plume was visible first, and then a large-scale disruption in the belt was observed that lasted for weeks after the eruption.

De Pater and her colleagues used ALMA to study the atmosphere below the plume and the disrupted belt at radio wavelengths and compared these to UV-visible light and infrared images made with other telescopes at approximately the same time.

“Our ALMA observations are the first to show that high concentrations of ammonia gas are brought up during an energetic eruption,” said de Pater. “The combination of observations simultaneously at many different wavelengths enabled us to examine the eruption in detail. Wich led us to confirm the current theory that energetic plumes are triggered by moist convection at the base of water clouds, which are located deep in the atmosphere. The plumes bring up ammonia gas from deep in the atmosphere to high altitudes, well above the main ammonia cloud deck,” she added.

“These ALMA maps at millimeter wavelengths complement the maps made with the National Science Foundation’s Very Large Array in centimeter wavelengths,” said Bryan Butler of the National Radio Astronomy Observatory. “Both maps probe below the cloud layers seen at optical wavelengths and show ammonia-rich gases rising into and forming the upper cloud layers (zones), and ammonia-poor air sinking down (belts).”

“The present results show superbly what can be achieved in planetary science when an object is studied with various observatories and at various wavelengths”. Explains Eric Villard, an ALMA astronomer part of the research team. “ALMA, with its unprecedented sensitivity and spectral resolution at radio wavelengths, worked together successfully with other major observatories around the world, to provide the data to allow a better understanding of the atmosphere of Jupiter.”

Additional Information

The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of the European Southern Observatory (ESO), the U.S. National Science Foundation (NSF) and the National Institutes of Natural Sciences (NINS) of Japan in cooperation with the Republic of Chile. ALMA is funded by ESO on behalf of its Member States, by NSF in cooperation with the National Research Council of Canada (NRC) and the Ministry of Science and Technology (MOST) in Taiwan and by NINS in cooperation with the Academia Sinica (AS) in Taiwan and the Korea Astronomy and Space Science Institute (KASI).

ALMA construction and operations are led by ESO on behalf of its Member States by the National Radio Astronomy Observatory (NRAO), managed by Associated Universities, Inc. (AUI), on behalf of North America and by the National Astronomical Observatory of Japan (NAOJ) on behalf of East Asia. The Joint ALMA Observatory (JAO) provides the unified leadership and management of the construction, commissioning and operation of ALMA.

Video

Images

Radio image of Jupiter made with ALMA. Bright bands indicate high temperatures and dark bands low temperatures. The dark bands correspond to the zones on Jupiter, which are often white at visible wavelengths. The bright bands correspond to the brown belts on the planet. This image contains over 10 hours of data, so fine details are smeared by the planet’s rotation. Credit: ALMA (ESO/NAOJ/NRAO), I. de Pater et al. NRAO/AUI NSF, S. Dagnello

Flat map of Jupiter in radio waves with ALMA (top) and visible light with the Hubble Space Telescope (bottom). The eruption in the South Equatorial Belt is visible in both images. Credit: ALMA (ESO/NAOJ/NRAO), I. de Pater et al. NRAO/AUI NSF, S. Dagnello NASA/Hubble

Spherical ALMA map of Jupiter showing the distribution of ammonia gas below Jupiter’s cloud deck. Credit: ALMA (ESO/NAOJ/NRAO), I. de Pater et al. NRAO/AUI NSF, S. Dagnello


What is germane doing in the atmosphere of Jupiter? - Astronomy

All planets show a differentiation in their structure: Denser elements sink to the center of the planet and lighter elements "float" to the outer layers of a planet. Models of Jupiter show that it has a rocky core surrounded by an icy mixture of water and ammonia that is surrounded by hydrogen and helium.

Now comes my question: If gases like ammonia, methane, etc. are denser than hydrogen, why are they present in Jupiter's atmosphere? Shouldn't they have "sunk" a long time ago?

Your question is a good one. The basic reason that there are gases heavier than hydrogen in the upper part of Jupiter's atmosphere is that Jupiter is hot enough that the methane, ammonia, etc. in the atmosphere are gaseous (they don't condense to a liquid), and the atmosphere is well mixed by convection.

As Jupiter was accreting material during its formation, it grew hot enough that water and other molecules became gaseous and formed an envelope around the growing core. As time went on and more and more material fell onto the planet, the gaseous envelope became larger. Planetesimals that impacted the planet late in its formation had trouble penetrating through the surrounding envelope which was quite thick. The impactors sublimated in the atmosphere and added their heavy elements to the upper part of the planet. The heat caused convection which distributed the heavy elements uniformly through the envelope. They weren't able to sink into the core.

Another way to picture this is to think of Earth. We have N2 and O2 in our atmosphere, and yet we don't have a layer of N2 on the bottom and then a layer of O2. Atmospheric gasses don't separate out like this because they are constantly mixed by convection caused by thermal gradients.

Also, Saturn and Jupiter will still differentiate more over time. We think this is happening in Saturn right now. Saturn has cooled to a temperature where the helium becomes immiscible (unable to stay dissolved) in the liquid metallic hydrogen layer. The helium "rains" out onto the core, which releases energy. This process can explain the extra energy we see Saturn giving off, as well as the depletion of helium in the atmosphere that we observe. This same process should happen in Jupiter as it cools, but we think Jupiter is still too hot. (Although some astronomers believe that it has actually started recently, and this explains the slightly lower than expected helium abundance in Jupiter's atmosphere.)


Jupiter's atmosphere harbours a 'unique meteorological beast'

Friday, March 19th 2021, 9:51 am - A comet impact in the 1990s is now providing insights into the incredibly powerful winds blowing above Jupiter's cloud tops.

Nearly three decades ago, a 2-kilometre-wide comet broke apart and plunged into the cloud layers of Jupiter. In just the past few years, astronomers have used the aftermath of that colossal impact to capture the first measurements of the planet's stratosphere. In doing so, they have revealed what they called a "unique meteorological beast in our Solar System."

When the shattered remnants of Comet Shoemaker-Levy 9 slammed into Jupiter in July of 1994, it was a fantastic sight. Images of the multiple impact sites were awe-inspiring, and from a safe distance, the event offered us a glimpse at what a comet impact really looks like. The event also provided a scientific boon that has only been realized now, in 2021.

In this composite image, fragments of comet Shoemaker-Levy 9 plunge towards Jupiter. The comet was imaged on May 17, 1994, with Jupiter imaged separately the day after, on May 18, 1994, both by the Hubble Space Telescope. Io and its shadow are visible as well. Credit: NASA, ESA, H. Weaver and E. Smith (STScI) and J. Trauger and R. Evans (NASA's Jet Propulsion Laboratory)

Although the bruising to Jupiter's cloud tops by Shoemaker-Levy 9 disappeared pretty quick, there was a long-lasting effect from this encounter. The pieces of the comet added chemical molecules to Jupiter's atmosphere. One, in particular, hydrogen cyanide, is apparently common for comets but doesn't normally exist on Jupiter.

Astronomers using radio telescopes such as the Atacama Large Millimeter/submillimeter Array (ALMA), located in northern Chile, have already detected the chemical fingerprint of hydrogen cyanide in comets like Comet ISON. Turning ALMA towards Jupiter back in 2017, a team led by Thibault Cavalié of the Laboratoire d'Astrophysique de Bordeaux in France was able to detect the hydrogen cyanide left behind by Shoemaker-Levy 9. They used it to do something no one had done before. They tracked the wind speeds in Jupiter's stratosphere.

This series of images captures the impact zones of comet Shoemaker-Levy 9 in 1994. Credit: ESO

Similar to Earth's atmosphere, Jupiter's atmosphere is divided into different layers. On both planets, the clouds we see are primarily located in the troposphere. Above that is a layer that is nearly devoid of clouds, known as the stratosphere. The lack of clouds makes it very difficult to directly measure wind speeds in the stratosphere. Here on Earth, we can get around the difficulty by simply launching a weather balloon. On Jupiter, though, we would need to sacrifice a billion-dollar spacecraft for just a brief glimpse at what stratospheric speeds are like.

Since hydrogen cyanide apparently does not break down in Jupiter's upper atmosphere, this presented a unique opportunity. As the molecules absorb heat and radiation, they emit various frequencies of light to get rid of that excess energy. Some of these frequencies are in the radio part of the spectrum. With ALMA already 'trained' to find the molecule's radio fingerprint, astronomers could use the chemical's movement through the air as a tracer.

This artist impression shows impact scars in Jupiter's clouds due to Shoemaker-Levy 9. Credit: ESO/M. Kornmesser/NASA/ESA

They discovered wind speeds of around 600 kilometres per hour in the stratosphere near Jupiter's equator. Wind speeds in Jupiter's polar jets — the concentrated 'ribbons' of wind around the north and south poles, similar to the jet streams here on Earth — were found to be substantially faster.

"The most spectacular result is the presence of strong jets, with speeds of up to 400 metres per second, which are located under the aurorae near the poles," Cavalié said in an ESO press release.

That's roughly equal to 1,450 kilometres an hour — over three times faster than the strongest wind speeds ever measured on Earth. The team's results appear in a new study, published in the journal Astronomy and Astrophysics on Thursday.

This artist's impression shows the stratospheric jets blowing around Jupiter's south polar region. Credit: ESO/L. Calçada & NASA/JPL-Caltech/SwRI/MSSS

The key to this was using ALMA to detect Doppler shifts in the radio frequencies emitted by the molecules. Doppler shifts cause a radio wave's frequency to increase if the wave is travelling towards your detector and decrease if the wave is travelling away from your detector.

"By measuring this shift, we were able to deduce the speed of the winds much like one could deduce the speed of a passing train by the change in the frequency of the train whistle," Vincent Hue, a co-author of the study from the Southwest Research Institute (SwRI), told the ESO.

"Our detection indicates that these jets could behave like a giant vortex with a diameter of up to four times that of Earth, and some 900 kilometres in height," co-author Bilal Benmahi, who is also at the Laboratoire d'Astrophysique de Bordeaux, said in the statement.

"A vortex of this size would be a unique meteorological beast in our Solar System," Cavalié added.

Studies like this provide better insights into the structure and properties of Jupiter's atmosphere. Surprises found during this type of research — such as discovering that strong wind speeds 'survive' to much deeper in Jupiter's atmosphere than previously thought — help advance planetary science and our understanding of how massive planets like Jupiter formed.


NMSU astronomers to analyze Jupiter’s atmosphere thanks to NASA grant

Hubble Space Telescope photo of Jupiter was taken when it was comparatively close to Earth, at a distance of 415 million miles. Hubble reveals the intricate, detailed beauty of Jupiter’s clouds as arranged into bands of different latitudes, known as tropical regions. These bands are produced by air flowing in different directions at various latitudes. Lighter colored areas, called zones, are high-pressure where the atmosphere rises. Darker low-pressure regions where air falls are called belts. The planet’s trademark, the Great Red Spot, is a long-lived storm roughly the diameter of Earth. Much smaller storms appear as white or brown-colored ovals. Such storms can last as little as a few hours or stretch on for centuries. (Photo: Images courtesy NASA, ESA, and A. Simon - NASA Goddard)

LAS CRUCES - The atmosphere of Jupiter is a colorful swirl of cloud bands in brown, yellow, red and white with an enormous red spot. To unlock some of the atmosphere’s mysteries on the gas giant planet, New Mexico State University researchers this week received a three-year, $283,800 grant from NASA’s New Frontiers Data Analysis Program.

The New Frontiers research program, within NASA’s Planetary Science Division, is aimed at enhancing the scientific return from New Frontiers class missions. The mission NMSU astronomers have chosen to investigate is the Juno mission, which is currently in orbit around Jupiter.

“We proposed to analyze some infrared images and spectra of Jupiter’s atmosphere to try to understand the circulation patterns and the waves, and the transition between orderly and chaotic circulations in Jupiter’s atmosphere,” said Nancy Chanover, astronomy professor and principal investigator on the project.

The team of researchers working with Chanover includes co-investigators Jason Jackiewicz, associate professor of astronomy Wladimir Lyra, assistant professor of astronomy and Ali Hyder, astronomy Ph.D. student.

The atmosphere of Jupiter is the largest in the solar system. It’s called a gas giant because its atmosphere is made up of mostly hydrogen and helium gas, like the Sun. Each of the professors is approaching the data from a different perspective. Chanover’s perspective is from the upper cloud deck of Jupiter, Jackiewicz studies the interior of Jupiter and vertical motions within the atmosphere, and Lyra creates numerical simulations of fluids of all astrophysical kinds.

“My part is in the modeling of the atmosphere. In this case, we are going to apply my models to the atmosphere of Jupiter to better understand and explain the observations recorded by Juno,” Lyra said as he described some of his previous simulations and how they could apply to the Jupiter project.

“This a previous model, so you can see as the simulation proceeds, more vortices form, they grow, they merge with other ones, they tease each other. In the end, you’re going to have one large vortex. So we are applying the same kind of calculations to the atmosphere of Jupiter.”

Jason Jackiewicz, associate professor of astronomy, is part of the team of researchers studying the atmosphere of Jupiter. Jackiewicz’s research, the NASA-funded Jovian Interiors from Velocimetry Experiment in New Mexico project, he has been using the Dunn Solar Telescope to measure winds in Jupiter’s atmosphere, in particular vertical motions with a very specific technique he pioneered. (Photo: Darren Phillips / New Mexico State University)

As part of Jackiewicz’s research, the NASA-funded Jovian Interiors from Velocimetry Experiment in New Mexico project, he has been using the Dunn Solar Telescope to measure winds in Jupiter's atmosphere, in particular vertical motions, with a very specific technique he pioneered. The data from Juno are being supplemented with observations from JIVE.

“It's exciting that we can obtain data from observations carried out right here in New Mexico that complement the NASA Juno space data, providing us with new constraints about how the atmosphere of Jupiter is dynamically linked to interesting features like vortices,” said Jackiewicz.

Little is known about the interior composition and structure of gas giant planets like Jupiter. One of NASA’s planetary science goals is to understand how the sun’s family of planets originated and evolve.

“The Juno images provide us sort of with east, west and north south motions of the clouds and Jason’s data will provide us with the vertical motions of the clouds,” Chanover said. “Using that three-dimensional dataset, we will really be able to probe what’s driving these vortices in the atmospheric circulation.”

Ph.D. student Ali Hyder will be working with the team on all aspects of the research as part of his doctoral thesis.

“Jupiter’s atmosphere is a dynamic and ever-changing system where we can observe fluid dynamic phenomenology on a scale inaccessible on Earth, so it provides a very unique environment in which to study such phenomena,” Hyder said. “Being part of this project, I will be working on all aspects of numerical modeling, the actual development of the code, modification of the model, analysis of the results from the numerical simulation, and the data reduction of the observations as well.”

From left: Wladimir Lyra, assistant professor of astronomy, Ali Hyder, Ph.D. student, and Nancy Chanover, astronomy professor and principal investigator of a three-year, $283,800 grant from NASA’s New Frontiers Data Analysis Program to analyze infrared images and spectra of Jupiter's atmosphere. (NMSU photo by ) (Photo: Amanda Adame / New Mexico State University)

Results of this research will be published in peer reviewed journals and the new data generated through the mapping of some images or the inclusion of these other datasets will be archived in the Atmospheres Node of NASA’s Planetary Data System, located at NMSU.

Chanover also leads that project, which is responsible for the acquisition, preservation and distribution of all non-imaging atmospheric data from all planetary missions (excluding Earth observations).

“Once the data are archived in the PDS, they are accessible by any investigator worldwide,” Chanover said. “It really provides value to the existing mission data that are in the archive, because now we’re adding what is known as derived data – or a kind of new data – generated as a result of those mission data. So we’re adding another layer on top of the primary mission data.”

The blending of different research specialties to make new discoveries about Jupiter is an important part of the project for Chanover.

“One of the reasons I'm really excited about this project is because it’s a true collaboration among three faculty members in our department who come from varied academic research areas.”

The collaborative nature is also a benefit for Hyder as a graduate student.

“It is a really big deal for me to get exposure to such a varied domain of expertise, which is quite unusual for a single project,” Hyder said. “So I’m getting information regarding the atmosphere, regarding the interior, and regarding numerical astrophysics all together.”


Katharina Doll

Katharina on a student visit to CERN, also known as European Organization for Nuclear Research. Credit: Katharina Doll

Education

How did you become a NASA citizen scientist?

Back in 2007, I got involved in classifying for Galaxy Zoo, which would later become the Zooniverse, and tried out several projects under the Zooniverse umbrella. It provided me with an option to learn more about astronomy (which my classmates and teachers considered a rather "exotic" hobby) and also to use my English skills beyond the classroom.

I discovered Disk Detective shortly after its launch and responded to the first call to submit objects for follow-up observing. The science team's interaction on the site's blog and discussion forum helped me to understand the scientific background of the front-end classifications. PI Marc Kuchner mentioned on the discussion forum that the science team had created an advanced user group. The science team helped me level up in quite a few ways. I could never have imagined the many ways in which my childhood interest in astronomy, combined with a casual involvement with what would become the Zooniverse, would provide a balance to my main course of study.

What are your favorite citizen science projects to work on?

Disk Detective and Backyard Worlds: Planet 9, but there are some other Zooniverse projects I like, too. (Unfortunately, my time is a bit limited.) There are many reasons: the subjects and the possibility of working on groundbreaking research, the way the science team members interact with the citizen scientists, and the community I have found among other citizen scientists, which involves learning from and with like-minded people. It's a nice atmosphere.

What do you do when you&rsquore not doing science with NASA? Tell us about your job and your hobbies!

I am a research assistant at the University of Augsburg [Germany], working on a legal history project on insurance law. I had studied law for the state examination and completed the two-year mandatory practical legal training (concluding with the second state examination), although I am currently not admitted to the bar. I have also worked on German constitutional and administrative law.

What have you discovered or learned as a NASA citizen scientist?

I have learned a lot about working with astronomy data &mdash vetting objects for follow-up observing after classification, reading papers, examining follow-up telescope data with specialist software (SAO DS9) to look for artifacts, etc. I am currently working to deepen my (still very basic) Python programming skills. I have also learned a lot about working with people from all over the world.

What first sparked your interest in space and science?

Probably in elementary school, when I visited the local amateur observatory with my parents during summer break. My parents always encouraged my curiosity about how and why things work, without forcing anything.

What advice would you give to others who might want to volunteer with NASA?

Just get started, be curious, don't be afraid to ask questions. People are friendly, and often the seemingly "dumb" questions you're afraid to ask are the most interesting ones.

What are some fun facts about yourself?

My interest in astronomy and involvement with the Zooniverse secured me a spot on a student excursion to CERN in Geneva. We got to tour the facilities and even see the CMS detector open for maintenance. Space and astronomy are also great topics to talk about with people from other fields &mdash I couldn't have imagined the deep conversations about astronomy I've had with some historians and lawyers!


We knew Jupiter was weird. Now we're finding out HOW weird.

If there’s one thing that shouldn’t surprise astronomers, it’s being surprised. The trend is pretty clear: Every single time we look at the Universe in a new way —bigger telescopes, different wavelengths (colors) of light, space probes equipped with better detectors— we find stuff that is massively unexpected. Being surprised is in no way surprising.

Yet here we are, surprised once again, standing in awe before the mightiest of the planets: Jupiter.

The Juno spacecraft entered Jupiter orbit on July 4, 2016, and is on a looping 53-day trajectory that takes it 8 million kilometers out from the planet, then drops it screaming in to just 4200 kilometers above the planet’s north pole, traveling at a terrifying 200,000 kilometers per hour (125,000 mph). It swings down the planet, over the south pole, and is flung out once again. The purpose of the mission is to help scientists understand how Jupiter formed and how it changed over time, to see how this affected its internal structure and in turn figure out how that affects what we see closer to the surface.

Juno just finished its sixth orbit, but scientists have published the results they found after the first couple of orbits (in two main papers and dozens of others). Even after that short period of time Juno has sent back a vast amount of data, enough to — say it with me now — surprise scientists.

A cleverly done animation cretaed using Juno images from the 5th pass over Jupiter's poles on March 27, 2017. Credit: NASA / SwRI / MSSS / Gerald Eichstädt / Seán Doran

One of the biggest questions scientists hope Juno will answer actually sounds pretty simple: Does Jupiter have a core? The Earth, for example, has a dense nickel/iron core, formed as those heavy metals fell to the center of our planet as it cooled. Jupiter, though, may not have one at all!

I always assumed it had one, but when I was researching Jupiter for my Crash Course Astronomy episode on it I found that may not be the case. It depends in part on how Jupiter itself formed. In the early solar system, a lot of material starting clumping together to form bigger and bigger objects, going from grains of sand to rubble to boulders to things which were starting to look like planets, called protoplanets. If a bunch of those smashed together to form Jupiter — creating it from the bottom up, so to speak — then yeah, it should have a dense rocky/metal core, probably more massive than our own planet.

It’s also possible Jupiter collapsed directly from the disk of gas and dust surrounding the Sun — from the top down. If that’s the case then it won’t have a core. I’ll note that it’s possible it could have started with a core, but it got eaten away by currents of hot metallic hydrogen deep inside the planet as well.

The presence of a core or lack thereof will change the way Jupiter’s gravitational field is shaped, and this in turn will affect Juno’s orbit. By carefully measuring the spacecraft’s trajectory, this jovian riddle can be solved!

Or maybe. Maybe not. The result scientists found after that first orbit is that Jupiter may have a core, but it’s . fuzzy. Dilute. It may be bigger than first thought, too, containing 7-25 times the mass of Earth (Jupiter’s total mass is 318 times Earth’s). I had to laugh when I read that I can imagine groups of scientists on either side of this issue arguing for years over whether Jupiter has a core or not, and then finding out that, in a way, they may both be right.

Mind you, though, that’s just after two orbits. There are a lot more to come. More information will hopefully equal more refined understanding.

This phenomenal image shows something never seen before: Jupiter's rings seen from between them and Jupiter itself! The bright star is Betelgeuse, and the three stars of Orion's belt can be seen at the bottom right. Credit: NASA/JPL-Caltech/SwRI

And still, that’s just the start of the weirdness.

When you look at Jupiter through a telescope, the most obvious features are its stripes. These are weather patterns whipped completely around the planet, and signify areas where the atmosphere is rising or falling (like convection cells on Earth). But what happens near the poles? That’s hard to tell from Earth, because we’re close to being in Jupiter’s equatorial plane, so the poles are distorted and blurred due to perspective of the curving planet.

Jupiter's south pole, seen from a distance of just over 50,000 km. Credit: NASA/JPL-Caltech/SwRI/MSSS/Betsy Asher Hall/Gervasio Robles

Juno travels directly over the poles, giving us a sharper view of them than ever before. And what it found is interesting: The familiar stripes break down at latitudes within 30° of the poles. Instead, the polar atmosphere is dominated by huge numbers of cyclonic storms moving around in a much darker background than at lower latitudes. But they’re different at the different poles: At the north pole, they range in size from 1400 km across down to Juno’s camera’s resolution of 50 km. In the south they’re more limited in size, from 200 – 1000 km. The storms’ distribution is different at the two poles as well. It’s not at all clear why the poles are so different.

The poles are also different than Saturn’s. There’s no large organized wave pattern like Saturn’s eerie hexagon (though a mild wave was detected, it’s nowhere near as obvious). Also, there’s no small, well-organized vortex like Saturn has at its north pole. Clearly, the forces operating at Jupiter’s poles are very different than Saturn’s. This is a new development, and I’m sure the planetary atmospheric scientists are working feverishly on the new data coming back from Juno to figure this out.

Swirls of clouds at Jupiter's mid-lsitudes, taken by Juno from a mere 8900 km above them on May 19, 2017. You can see the white clouds are actually higher up and only about 25 km in size. Credit: NASA/SWRI/MSSS/Gerald Eichstadt/Sean Doran

At the equator, another mystery literally arises. A main constituent of Jupiter’s atmosphere is ammonia. It forms white clouds in rising, cooling air and scientists assumed that below the clouds it was mixed in with everything else. What they found in the Juno data is this isn’t the case. There’s a plume of ammonia right a the equator from deep inside the atmosphere, from a depth where the pressure is about 60 times the Earth’s atmospheric pressure at sea level. This was completely unexpected, and means that the models of how Jupiter’s atmosphere works need to be looked at again.

Juno mapped the location of ammonia in Jupiter's atmosphere. The equatorial plume was a surprise. Credit: NASA/JPL-Caltech/SwRI

The giant planet’s magnetic field is different than expected, too. It’s far more powerful than Earth’s (we already knew that!) but it varies spatially in strength more than expected. Like Earth’s magnetism, Jupiter’s is created deep under the surface, so the composition and structure inside Jupiter is different than expected (which at least jibes with what is seen in the gravitational studies looking for the core). Juno data implies that Jupiter’s magnetic field is generated not only in the core but may be influenced by material above the core, which is very different than here on (well, under) Earth. That was unexpected.

And if I had to pick one more weirdness out of everything, it’s what’s happening in Jupiter’s aurorae. On Earth, these are created when subatomic particles from the Sun’s solar wind are captured by Earth’s magnetic field and funneled down into our atmosphere at the poles. The particles slam into the air, which strips off electrons from the atoms and molecules. When the electrons recombine, they emit light, causing the aurorae.

On Jupiter, Juno showed that this happens as well, but also electrons are stripped off the atmosphere of the planet and sent up into space above the poles. That was unexpected, and must have to do with Jupiter’s more intense magnetic field strength, but the detailed mechanism is, for now, unknown.

Now look, I can see where it might seem like this is all very esoteric, but it has an interesting implication. We learned most of what we know about the way planets work by studying our own and then comparing and contrasting what we think we understand with what we see happening on other planets. But if we see things that don’t work there as they do here, does that mean conditions really are different there, or that some of our assumptions about Earth need to be updated? We really do understand a lot about the Earth, but there could be some pieces missing that we need to figure out. We can only do that by observing these other worlds.

Only by venturing away from our home do we come to understand it, and perhaps more importantly come to understand what we don’t understand. We must explore space so that we can explore our own world. Looking outward is looking inward.

And the good news is that there’s a lot more to come. There are a dozen or more orbits still ahead, so we’ll get better data as time goes on. Sadly, the ridiculously harsh radiation environment so close to Jupiter will take its toll, and the JunoCam, which has provided the incredibly rich and detailed images we’ve seen, will eventually succumb. But the images, spectacular as they are, do not provide the main science Juno is doing the other instruments are better protected inside the spacecraft. It’ll be tough when we stop getting these phenomenal images, but the scientists will continue to get more data as the mission itself continues.


Affiliations

Université Côte d’Azur, OCA, Lagrange CNRS, 06304, Nice, France

School of Physics and Astronomy, University of Leicester, University Road, Leicester, LE1 7RH, UK

You can also search for this author in PubMed Google Scholar

You can also search for this author in PubMed Google Scholar

Contributions

T.G. wrote the parts of this article focussing on planetary interiors L.N.F. wrote parts of this article discussing planetary atmospheres. Both authors reviewed and edited this article.

Corresponding author