“Mystery of Jupiter’s X-Ray Auroras Solved” — Ends a 40-year Quest

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The Daily Galaxy, Maxwell Moe, astrophysicist, NASA Einstein Fellow, University of Arizona via University College London - Jul 13, 2021 in Astronomy, Science, Solar System

solar-wind-powered-aurora-s-at-jupiter -s-poles-heating.jpg
Hubble telescope picture shows the aurora of glowing gas wrapped around Jupiter’s north pole . This curtain of light is produced when high-energy electrons race along the planet’s magnetic field and into the upper atmosphere where they excite atmospheric gases, causing them to glow. This Hubble image, taken in ultraviolet light, also shows the glowing “footprints” of three of Jupiter’s largest moons: Io, Ganymede, and Europa. NASA/ESA, John Clarke (University of Michigan)

“We have seen Jupiter producing X-ray aurora for four decades, but we didn’t know how this happened. We only knew they were produced when ions crashed into the planet’s atmosphere,” says William Dunn at the University College London (UCL) Mullard Space Science Laboratory about the eerie, electric-blue curtains of light glowing one half billion miles away on the gas giant.

The X-rays are part of Jupiter’s aurora—bursts of light that occur when charged particles interact with the planet’s atmosphere and magnetic field. Jupiter’s magnetic field is extremely strong—about 20,000 times as strong as Earth’s—and therefore its magnetosphere, the area controlled by this magnetic field, is extremely large. If the aurora was visible in the night sky, it would cover a region several times the size of our moon.

The image aboveshows the main oval of the aurora, which is centered on the magnetic north pole, plus more diffuse emissions inside the polar cap.

A similar phenomenon occurs on Earth, explains researchers at University College London (UCL), creating the northern lights, but Jupiter’s is much more powerful, releasing hundreds of gigawatts of power, enough to briefly power all of human civilization.

In a new study, published in Science Advances, UCL researchers combined close-up observations of Jupiter’s environment by NASA’s satellite Juno, which is currently orbiting the planet, with simultaneous X-ray measurements from the European Space Agency’s XMM-Newton observatory (which is in Earth’s own orbit).

jupiter aurora.jpg
These overlaid images of Jupiter’s poles were taken from NASA’s satellite Juno and NASA’s Chandra X-ray telescope. Left shows a projection of Jupiter’s Northern X-ray aurora (purple) overlaid on a visible Junocam image of the North Pole. Right shows the Southern counterpart. Credit: NASA Chandra/Juno Wolk/Dunn

The research team, led by UCL and the Chinese Academy of Sciences, discovered that X-ray flares were triggered by periodic vibrations of Jupiter’s magnetic field lines. These vibrations create waves of plasma (ionized gas) that send heavy ion particles “surfing” along magnetic field lines until they smash into the planet’s atmosphere, releasing energy in the form of X-rays.

View: https://www.youtube.com/watch?v=dplSgv6qlMk


“Now we know these ions are transported by plasma waves—an explanation that has not been proposed before, even though a similar process produces Earth’s own aurora. It could, therefore, be a universal phenomenon, present across many different environments in space.”

For the first time, astronomers have seen the way Jupiter’s magnetic field is compressed, which heats the particles and directs them along the magnetic field lines down into the atmosphere of Jupiter, sparking the X-ray aurora. The connection was made by combining in-situ data from NASA’s Juno mission with X-ray observations from ESA’s XMM-Newton. Credit: ESA/NASA/Yao/Dunn

X-ray auroras occur at Jupiter’s north and south poles, often with clockwork regularity. During this observation, Jupiter was producing bursts of X-rays every 27 minutes.

The charged ion particles that hit the atmosphere originate from volcanic gas pouring into space from giant volcanoes on Jupiter’s moon, Io. The gas becomes ionized (its atoms are stripped free of electrons) due to collisions in Jupiter’s immediate environment, forming a donut of plasma that encircles the planet.

“Now we have identified this fundamental process, there is a wealth of possibilities for where it could be studied next,” says co-lead author Dr. Zhonghua Yao (Chinese Academy of Sciences, Beijing). “Similar processes likely occur around Saturn, Uranus, Neptune and probably exoplanets as well, with different kinds of charged particles ‘surfing’ the waves.”

“X-rays are typically produced by extremely powerful and violent phenomena such as black holes and neutron stars, so it seems strange that mere planets produce them too. We can never visit black holes, as they are beyond space travel, but Jupiter is on our doorstep,”observes co-author professor Graziella Branduardi-Raymont (UCL Mullard Space Science Laboratory). “With the arrival of the satellite Juno into Jupiter’s orbit, astronomers now have a fantastic opportunity to study an environment that produces X-rays up close.”

For the new study, researchers analyzed observations of Jupiter and its surrounding environment carried out continuously over a 26-hour period by the Juno and XMM-Newton satellites.

They found a clear correlation between waves in the plasma detected by Juno and X-ray auroral flares at Jupiter’s north pole recorded by XMM Newton. They then used computer modeling to confirm that the waves would drive the heavy particles towards Jupiter’s atmosphere.

Why the magnetic field lines vibrate periodically is unclear, but the vibration may result from interactions with the solar wind or from high-speed plasma flows within Jupiter’s magnetosphere.

See: https://dailygalaxy.com/2021/07/mystery-of-jupiters-x-ray-auroras-solved-ends-a-40-year-quest/#utm_source=rss&utm_medium=rss&utm_campaign=mystery-of-jupiters-x-ray-auroras-solved-ends-a-40-year-quest

It is very cool to find that the clockwork regularity of the 27 hour appearance of Jupiter's X-ray auroras coincide with the phased pumped charged ion particles originating from the volcanic gas on Io which strike Jupiter's atmosphere. The gas becomes ionized due to collisions in Jupiter's immediate environment, forming a plasma donut that encircles the giant planet.

JupiterRadioImage13cm..jpg
The radio image of Jupiter on this page were recorded by the Australia Telescope National Facility (ATNF) of the Commonwealth Scientific and Industrial Research Organisation (CISRO). The Australia Telescope is a set of eight radio-receiving dish antennas at three sites in New South Wales. It is the largest single astronomical institution in Australia.

As Io's orbital motion carries it through this magnetized ring of ionized gas, a huge electrical current flows between Io and Jupiter. Carrying about two trillion watts of power, it's the biggest DC electrical circuit in the Solar System. You may tune into Jupiter at 20 Mhz. From the shortwave receiver, the so-called "L-burst" sounds like ocean waves crashing on a distant beach, while the S-burst sound like eerie drifting whistlers.
Hartmann352
 
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So this is similar to Earths aurora borealis, I could have figured this out in several seconds
While many processes are similar, Jupiter's aurora processes create X-ray flares which are triggered by periodic vibrations of Jupiter’s magnetic field lines. These vibrations, in turn, create waves of plasma (ionized gas) that send heavy ion particles “surfing” along magnetic field lines until they smash into the planet’s atmosphere, releasing energy in the form of X-rays. X-rays are typically produced by extremely powerful and violent phenomena such as black holes and neutron stars, so it seems strange that mere planets, even a gas giant like Jupiter, can also produce them. The difference between our rather benign aurora borealis, which some people can hear crackle, and Jupiter's is the creation of these X-rays, which are inimical to life at the energies they are created. I'm not sure that our north polar regions would be so conducive to civilization if our planet's aurora was showering the residents of Siberia, Alaska, Canada and Scandinavia with a shower of X-rays every 27 minutes.
Hartmann352
 
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How are vibrations of Jupiters magnetic field lines detected?

Which raises the question how are Jupiters magnetic field lines detected in the first place?

This article is actually 100 percent speulation, like nothing can escape a black hole, until it is now speculated that radiation escapes.

No one knows anything
The first detection of the aurora and the basic magnetic flux lines was by the Voyager 1 UVS during its Jupiter encounter in spring 1979, followed within a couple of months by observations from the International Ultraviolet Explorer (IUE) from Earth orbit. The UV auroral emissions closely resemble the laboratory spectrum of electron collisional excitation of H2.

Additional UV auroral emissions result from fast proton and H atom collisional excitation. During the Voyager 1 and 2 encounters the long aperture of the UVS was used to map the equatorward extent of the UV auroral emissions. These maps indicated that auroral emissions first appeared when the end of the aperture covered the expected latitude of the magnetic mapping of the plasma torus into Jupiter's atmosphere, seemingly implicating the plasma torus as the source of auroral particles.

A detailed analysis of a series of STIS images obtained as Cassini approached Jupiter and they revealed several systematic trends in the aurora. New "reference" oval locations were defined based on the sums of images in the north and south, and the overall auroral morphology was shown to be fixed in jovian System III coordinates over at least 5 years time. The main oval was found to contract slightly near local noon, and to contract with an overall brightening on one day, apparently correlated with increased solar wind pressure. Comparison of auroral images with Cassini and Galileo measurements provided evidence of diffuse emissions mapping to the instantaneous position of Galileo at rv15 RJ where the Galileo EPD instrument de- tected plasma injection events.

This is the first case of simultaneous auroral imaging and measurement of the responsible precipitating particles on a planet other than the Earth. Simultaneous images at UV and X- ray wavelengths showed that strong X-ray emissions are produced in the "active region" where UV flares are also observed.

The Jovian magnetosphere is so large that the Sun and its visible corona would fit inside it with room to spare. If one could see it from Earth, it would appear five times larger than the disc of the full moon in the sky despite being nearly 1700 times farther away.

Currents_in_Jovian_Magnetosphere.png
Edwards, T.M.; Bunce, E.J.; Cowley, S.W.H. (2001). "A note on the vector potential of Connerney et al.’s model of the equatorial current sheet in Jupiter’s magnetosphere". Planetary and Space Science 49: 1115–1123. DOI:10.1016/S0032-0633(00)00164-1.
Cowley, S.W.H.; Bunce, E.J. (2001). "Origin of the main auroral oval in Jupiter’s coupled magnetosphere–ionosphere system". Planetary and Space Sciences 49: 1067–66. DOI:10.1016/S0032-0633(00)00167-7


The Cassini spacecraft's ion and neutral camera first detected neutral atoms expelled from the magnetosphere, deriving information about their source. This image of Jupiter's magnetosphere was taken shortly after Cassini's closest approach to Jupiter, about 10 million kilometers (6 million miles) from the planet on Dec. 30, 2000.

juoiter's magnetic field made visible.jpg
See: http://saturn.jpl.nasa.gov.

The main driver of Jupiter's magnetosphere is the planet's rotation. Jupiter is similar to a device called a Unipolar generator. When Jupiter rotates, its ionosphere moves relative to the dipole magnetic field of the planet. Because the dipole magnetic moment points in the direction of the rotation, the Lorentz Force, which appears as a result of this motion, drives negatively charged electrons to the poles, while positively charged ions are pushed towards the equator. As a result, the poles become negatively charged and the regions closer to the equator become positively charged. Since the magnetosphere of Jupiter is filled with highly conductive plasma, the electrical circuit is closed through it. A direct current then flows along the magnetic field lines from the ionosphere to the equatorial plasma sheet. This current then flows radially away from the planet within the equatorial plasma sheet and finally returns to the planetary ionosphere from the outer reaches of the magnetosphere along the field lines connected to the poles. The currents that flow along the magnetic field lines are generally called field-aligned or Birkeland Currents. This radial current interacts with the planetary magnetic field, and the resulting Lorentz force accelerates the magnetospheric plasma in the direction of planetary rotation. This is the main mechanism that maintains co-rotation of the plasma in Jupiter's magnetosphere.

The current flowing from the ionosphere to the plasma sheet is especially strong when the corresponding part of the plasma sheet rotates slower than the planet. As mentioned above, co-rotation breaks down in the region located between 20 and 40 RJ from Jupiter. This region corresponds to the magnetodisk, where the magnetic field is highly stretched. The strong direct current flowing into the magnetodisk originates in a very limited latitudinal range of about 16 ± 1° from the Jovian magnetic poles. These narrow circular regions correspond to Jupiter's main auroral ovals. The return current flowing from the outer magnetosphere beyond 50 RJ enters the Jovian ionosphere near the poles, closing the electrical circuit. The total radial current in the Jovian magnetosphere is estimated at 60 million–140 million amperes.

Again, this magnetic flux was observed by the Voyager, International Ultraviolet Explorer (IUE) Spacecraft, the Cassini, Galileo and now the Juno spacecraft.

See: https://solarsystem.nasa.gov/resources/1054/jupiters-magnetic-field-visualization/

See: http://www.pas.rochester.edu/~blackman/ast104/jmagnetic.html

See: https://solarsystem.nasa.gov/resources/11663/jupiters-magnetosphere/

Interestingly, the Juno spacecraft, in orbit around Jupiter in hopes of determining how Jupiter formed and has evolved over time by measuring its magnetic fields, studying its northern and southern auroras and measuring elements of its atmosphere — including temperature, cloud movement, and water concentrations. This past January it picked up a brief FM signal, called a “decametric radio emission" through a process called cyclotron maser instability, where electrons oscillate at a lower rate than they spin which causes them to amplify radio waves rapidly.

Though a significant discovery, the orbiting spacecraft was only able to pick up the radio emissions for just five seconds as Juno hurtled by Ganymede at a blinding speed of 111,847 mph. That's fast enough to cross the entire United States coast to coast in just under two minutes.
Listen to this decametric radio emission below:

See: https://fmuser.net/content/?8563.html

The size and sheer electrical power within Jupiter's magnetic field is truly awe inspiring when you imagine some 60-140 million amperes of electricity snapping overhead with the addition of a cascade of X-rays blasting through you every 27 minutes. Jupiter, our failed star, and its system of moons is truly a hellish place. However, when we viewed the crash of the Shoemaker-Levi comet's pieces into Jupiter's cloud tops we also realize that Jupiter, the king of the planets, helps sweep up those deadly incoming missiles from the Oort Cloud which would wreak havoc on Earth and might, like that nameless Earth shaking comet which gouged out the Chicxulub crater which ended the dinosaurs at the KT Boundary, end our civilization without the help of Jupiter's immense gravity and enormous magnetic field.
Hartmann352
 
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Uh huh, did you read the Hawking book that detailed clearly that nothing could escape a black hole? Until it became speculated that radiation does escape allowing the black hole to vanish. Jupiter is a gas giant, no human knows what is under the first visible layer of gas. Period
Yes, I have read all of Hawking's and some of Penrose's books.

Now, you mention the process involving a black hole radiating a thermal spectrum of particles due to quantum field theoretic effects in a classical gravitational background.

The decay of a black hole can also be viewed as the dissipative evolution of the black-hole geometry (internal string states) interacting with the environment (non-local modes). Raine and Sciama "Black Holes and Thermodynamics"* have also discussed that black hole decay can be viewed as the dissipative quantum evolution of the black hole interacting with a dissipative vacuum and the evaporation process is associated with the infalling 'negative Casimir energy'** in much the same way that the Lamb shift*** is represented by a change in the energy of the vacuum due to the presence of the atom.

This is the Hawking radiation. The particle number measured at I of a particular mode is given by
⟨nJ⟩= ΓJ , (12) exp[(2πω ̄ )/κ]±1
where the index J denotes collectively frequency ω, angular momentum l, azimuthal
quantum number m, sign of the charge, and spin. The upper sign is for fermions and
the lower sign for bosons. Here the quantity ω ̄ is defined as ω ̄ = ω − m Ω − JJjH
page9image1564435088
qΦH , and ΓJ denotes the fraction of the incident radiation that enters the collapsing body, i.e. Γ = 1 − |R |2

Hawking radiation is completely identical to black body radiation, since the density matrices for Hawking radiation and black body radiation coincide. Furthermore, it was shown that black holes behave like black bodies even in the presence of incoming radiation. Expressions for the probability of emission of k particles when m particles have arrived, P(k|m), and the Einstein coefficients for induced emission, spontaneous emission and absorptions were obtained in. The derivation of Hawking radiation was repeated subsequently in various approaches and generalizations.

See : https://heasarc.gsfc.nasa.gov/docs/xte/whatsnew/wardzinski_phd.pdf

See: https://journals.tubitak.gov.tr/physics/issues/fiz-00-24-4/fiz-24-4-3-97084.pdf

Randolph, let me reaffirm that all the elements of Jupiter's magnetosphere are exterior to the massive planet's surface and this magnetic flux was first detected by Voyager and later by the International Ultraviolet Explorer (IUE) Spacecraft in Earth orbit, the Cassini, Galileo and now the Juno spacecraft, all observed the magnetosphere outside Jupiter.

However, when it comes to trying to get a handle on Jupiter's interior, NASA's Galileo spacecraft carried an atmospheric entry probe which was released July 13, 1995, when the main spacecraft was still about 50 million miles (80 million kilometers) from Jupiter. The probe hit the atmosphere Dec. 7, 1995, and returned valuable atmospheric data for 61 minutes.

Interestingly, the probe slammed into Jupiter's atmosphere at 106,000 mph (170,590 kilometers per hour), fast enough to jet from Los Angeles to New York in 90 seconds. Deceleration to about Mach 1—the speed of sound—took just a few minutes. At maximum deceleration, as the craft slowed from 106,000 mph to 100 mph (160 kilometers per hour) it experienced a force 350 times Earth's gravity, or 350g. The incandescent shock wave ahead of the probe was as bright as the Sun and reached searing temperatures of up to 28,000 degrees Fahrenheit (15,537 degrees Celsius).

The probe’s transmitter eventually failed when the spacecraft was about 112 miles (180 kilometers) below its entry ceiling, evidently due to the enormous pressure (22.7 atmospheres) squeezing the craft and crushing its instruments.

The data, originally transmitted to the main spacecraft and later transmitted back to Earth, indicated an intense radiation belt about 31,000 miles (50,000 kilometers) above Jupiter’s clouds, few organic compounds, and winds as high as about half a mile per second (640 meters per second), or some 1,800 miles per hour.

The entry probe also found less lightning, less water vapor, and half the helium than had been expected in the upper atmosphere.

The Galileo orbiter, meanwhile, became Jupiter's first man-made satellite on Dec. 8, 1995.

During its nearly eight-year mission around Jupiter, Galileo returned an unprecedented amount of data on the planet and its environs.

Because Galileo had not been sterilized, it was decided to have the vehicle burn up in the Jovian atmosphere after its mission ended instead of risking impact on one of Jupiter's moons such as Europa to prevent any Earth-borne contamination.

Having completed its 35th orbit around Jupiter and after accompanying the planet for three-quarters of a circuit around the Sun, Galileo flew into the atmosphere at a velocity of 30 miles per second (48.2 kilometers per second), 108,000 miles per hour, just south of the equator, on Sept. 21, 2003, ending its mission.

See: https://www.jpl.nasa.gov/news/galileo-to-release-jupiter-atmospheric-probe

See: https://solarsystem.nasa.gov/missions/galileo-probe/in-depth/

* See: https://ui.adsabs.harvard.edu/abs/1976VA.....19..385S/abstract

** Negative Casimir energy: two flat plates placed very close together to restrict the wavelengths of quanta which can exist between them. This in turn restricts the types and hence number and density of virtual particle pairs which can form in the intervening vacuum and can result in a negative energy density. This causes an attractive force between the plates, which has been measured.

See: https://en.wikipedia.org/wiki/Negative_energy

*** The Lamb shift - According to the hydrogen Schrodinger equation solution, the energy levels of the hydrogen electron should depend only on the principal quantum number n. In 1951, Willis Lamb discovered that this was not so - that the 2p(1/2) state is slightly lower than the 2s(1/2) state resulting in a slight shift of the corresponding spectral line (the Lamb shift).

It might seem that such a tiny effect would be deemed insignificant, but in this case that shift probed the depths of our understanding of electromagnetic theory.

See: http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/lamb.html

Jupiter's magnetosphere, which lies far above and trails beyond the gigantic planet, has been fleshed by both Earthbound and missions sent into Jupiter space. While we may not know know everything which lies beneath Jupiter's formidable looking atmosphere and its 1800 mph winds, we are getting better informed all the time. And, perhaps most uniquely, we can tune in Jupiter with a shortwave radio by turning the dial to 22 MHz with a good wire antenna.

While the formula for Hawking radiation looks difficult, the above shows and explains all of its components.

Physics is marvelous.
Hartmann352
 
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Dude you can stop pretending to be smart over black holes because you do not know anything about them, no one does. What happens is that people like Hawking pretend to know then humiliate themselves when they are proven wrong by newer measurements. So just stop telling us what you think that you know, unless you make it clear at the onset that no one knows anything including you. Seriously the new galactic speed measurements have physicist now speculating that there is no universe there at all because we are just part of a computer program, which means that there are no black holes and that there is no us.
There is every reason for you to remain a gentleman about our discussions here. I am not "dude", if I can address you as Randolph, you may address me as Hartmann352. The story of science is not one of "humiliation", but of one generation of scientists, who have an ever greater access to recent discoveries, standing on the shoulders of their predecessors.
 
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Stephen Hawking sold millions of dollars of books written as claimed science when the books contained nothing more than his personal wet dream and a way to support his crippled mind and body. You were a victim of his quackery as you admit to buying his nonsense as Hawking was a liar and a cheat.


In reality, according to the article you have supplied, what's happening is that the curved space around the black hole is constantly emitting radiation due to the curvature gradient around it, and that the energy is coming from the black hole itself, causes its event horizon to slowly shrink over time.

Black holes are not decaying because there's an infalling virtual particle carrying negative energy, according to Hawking. Instead, black holes are decaying, and losing mass over time, because the energy emitted by this Hawking radiation is slowly reducing the curvature of space in that region. Once enough time passes, and that duration is enormous for realistic black holes, they will have evaporated entirely.

However, if you have read all of Hawking's work, including the studies substantiating his science, except, for a "Brief History of Time", you'll find that this preeminent physicist deserved all the accolades he received. Hawking developed a mathematical proof for black holes and proved Einstein's theory of general relativity. Through math and science, Stephen redefined the Big Bang theory and he proved the universe has no boundaries (that it is finite but unbounded).

Roger Penrose, who studied under Hawking, won the 2020 Nobel Prize in Physics for having "used ingenious mathematical methods in his proof that black holes are a direct consequence of Albert Einstein’s general theory of relativity.*” In the 1970s, Penrose collaborated with Stephen Hawking at Cambridge and in 1988, they shared the Wolf Foundation Prize for Physics for the Penrose–Hawking singularity theorems**.

* Penrose 2020 Nobel Prize Physics: "A black hole is a supermassive compact object with a gravitational force so large that nothing, not even light, can escape from it. In 1964, Roger Penrose proposed critical mathematical tools to describe black holes. He showed that Einstein’s general theory of relativity means the formation of black holes must be seen as a natural process in the development of the universe. He was also able to describe black holes in detail: at their farthest depths is a singularity where all known laws of nature dissolve."

See: https://www.nobelprize.org/prizes/physics/2020/penrose/facts/

** Penrose-Hawking singularity theorems: There are two physical situations where we expect for General Relativity to break down. The first is the gravitational collapse of certain massive stars when their nuclear fuel is spent. The second one is the far past of the universe when the density and temperature were extreme. In both cases, we expect that the geometry of spacetime will show some pathological behavior.

See: https://physics.stackexchange.com/questions/66064/can-anyone-please-explain-hawking-penrose-singularity-theorems-and-geodesic-inco

Again, let's leave the discussion of Hawking alone for now and simply agree that we disagree on descriptions of the now dead physicist.
Hartmann352
 
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