First results from long-term, hi-res tracking of eruptions on Jupiter's moon Io

October 20, 2016, University of California - Berkeley
Images of Io at different near-infrared wavelengths. The name of the filter used is indicated in the black box at the start of each section. The bright spots are thermal emissions from Io's myriad volcanoes. Note the increasing number of hot spots detected at longer wavelengths, i.e. towards the bottom of the figure. Credit: Katherine de Kleer and Imke de Pater, UC Berkeley

Jupiter's moon Io continues to be the most volcanically active body in the solar system, as documented by the longest series of frequent, high-resolution observations of the moon's thermal emission ever obtained.

Using near-infrared on two of the world's largest telescopes - the 10-meter Keck II and the 8-meter Gemini North, both located near the summit of the dormant volcano Maunakea in Hawaii - University of California, Berkeley astronomers tracked 48 volcanic hot spots on the surface over a period of 29 months from August 2013 through the end of 2015.

Without adaptive optics - a technique that removes the atmospheric blur to sharpen the image - Io is merely a fuzzy ball. Adaptive optics can separate features just a few hundred kilometers apart on Io's 3,600-kilometer-diameter surface.

"On a given night, we may see half a dozen or more different hot spots," said Katherine de Kleer, a UC Berkeley graduate student who led the observations. "Of Io's hundreds of active volcanoes, we have been able to track the 50 that were the most powerful over the past few years."

She and Imke de Pater, a UC Berkeley professor of astronomy and of earth and , observed the heat coming off of active eruptions as well as cooling lava flows and were able to determine the temperature and total power output of individual volcanic eruptions.They tracked their evolution over days, weeks and sometimes even years.

Interestingly, some of the eruptions appeared to progress across the surface over time, as if one triggered another 500 kilometers away.

All hot spots detected from August 2013 through December 2015 are displayed on a full map of Io, illustrating the approximate length of time they were visible. The size of the circle corresponds logarithmically to the intensity. Loki Patera is at 310 West, 10 North and Kurdalagon Patera is at 220 West, 50 South. Credit: Katherine de Kleer and Imke de Pater, UC Berkeley.

"While it stretches the imagination to devise a mechanism that could operate over distances of 500 kilometers, Io's volcanism is far more extreme than anything we have on Earth and continues to amaze and baffle us," de Kleer said.

De Kleer and de Pater will discuss their observations at a media briefing on Oct. 20 during a joint meeting of the American Astronomical Society's Division for Planetary Sciences and the European Planetary Science Congress in Pasadena, California. Papers describing the observations have been accepted for future publication by the journal Icarus.

Tidal heating

Io's intense volcanic activity is powered by —heating from friction generated in Io's interior as Jupiter's intense gravitational pull changes by small amounts along Io's orbit. Models for how this heating occurs predict that most of Io's total volcanic power should be emitted either near the poles or near the equator, depending on the model, and that the pattern should be symmetric between the forward- and backward-facing hemispheres in Io's orbit (that is, at longitudes 0-180 degrees versus 180-360 degrees).

That's not what they saw. Over the observational period, August 2013 through December 2015, the team obtained images of Io on 100 nights. Though they saw a surprising number of short-lived but intense eruptions that appeared suddenly and subsided in a matter of days, every single one took place on the trailing face of Io (180-360 degrees longitude) rather than the leading face, and at higher latitudes than more typical eruptions.

"The distribution of the eruptions is a poor match to the model predictions," de Kleer said, "but future observations will tell us whether this is just because the sample size is too small, or because the models are too simplified. Or perhaps we'll learn that local geological factors play a much greater role in determining where and when the volcanoes erupt than the physics of tidal heating do."

All hot spot detections from August 2013 through December 2015 shown on a full map of Io. Each circle represents a new detection; the size of the circle corresponds logarithmically to the intensity, and more opaque regions are where a hot spot was detected multiple times. The color and symbol indicate the type of eruption, following the legend. Loki Patera is at 310 West, 10 North and Kurdalagon Patera is at 220 West, 50 South. Credit: Katherine de Kleer and Imke de Pater, UC Berkeley

One key target of interest was Io's most powerful persistent volcano, Loki Patera, which brightens by more than a factor of 10 every 1-2 years. A patera is an irregular crater, usually volcanic.

Many scientists believe that Loki Patera is a massive lava lake, and that these bright episodes represent its overturning crust, like that seen in lava lakes on Earth. In fact, the heat emissions from Loki Patera appear to travel around the lake during each event, as if from a wave moving around a lake triggering the destabilization and sinking of portions of crust. Prior to 2002, this front seemed to travel around the cool island in the center of the lake in a counter-clockwise direction.

After an apparent cessation of brightening events after 2002, de Pater observed renewed activity in 2009.

"With the renewed activity, the waves traveled clockwise around the lava lake," she noted.

Another volcano, Kurdalagon Patera, produced unusually hot eruptions twice in the spring of 2015, coinciding with the brightening of an extended cloud of neutral material that orbits Jupiter. This provides circumstantial evidence that eruptions on the surface are the source of variability in this neutral cloud, though it's unclear why other eruptions were not also associated with brightening, de Kleer said.

De Kleer noted that the Keck and Gemini telescopes, both atop the dormant volcano Maunakea, complement one another. Gemini North's queue scheduling allowed more frequent observations - often several a week - while Keck's instruments are sensitive also to longer wavelengths (5 microns), showing cooler features such as older lava flows that are invisible in the Gemini observations.

The astronomers are continuing their frequent observations of Io, providing a long-term database of high spatial resolution images that not even Galileo, which orbited Jupiter for eight years, was able to achieve.

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blazmotronic
1 / 5 (6) Oct 20, 2016
It is impossible to have such a small celestial body that is
4.5 billion years old to be active..the observations are a hoax!
FineStructureConstant
5 / 5 (9) Oct 21, 2016
...the observations are a hoax
What a perfectly ridiculous comment.
cantdrive85
1.6 / 5 (7) Oct 21, 2016
Interestingly, some of the eruptions appeared to progress across the surface over time,

The alleged moving volcanoes, of course volcanoes cannot move but electric discharge can.
"While it stretches the imagination to devise a mechanism that could operate over distances of 500 kilometers,..."

When gravity is the only possible culprit (in their minds), then yes it stretches the imagination and physics to "devise" a mechanism. Electric discharge doesn't share the same limitations gravitational reasoning is constrained.
"The distribution of the eruptions is a poor match to the model predictions,"

Psst, don't tell jonesdumb, it's easier for him to just ignore this fact.

cantdrive85
1.6 / 5 (7) Oct 21, 2016
In fact, the heat emissions from Loki Patera appear to travel around the lake during each event, as if from a wave moving around a lake triggering the destabilization and sinking of portions of crust. Prior to 2002, this front seemed to travel around the cool island in the center of the lake in a counter-clockwise direction.

The "Super Stupendous Traveling Volcano" with it's focused heat sources as if what they are actually observing is an electric discharge event that their blinded by ignorance eyes are incapable of understanding.
Anda
5 / 5 (7) Oct 22, 2016
As wise @FineStructureConstant said,
What a perfectly ridiculous comment...
Whydening Gyre
5 / 5 (7) Oct 22, 2016
The "Super Stupendous Traveling Volcano" with it's focused heat sources as if what they are actually observing is an electric discharge event that their blinded by ignorance eyes are incapable of understanding.

Said the guy blinded by - well, his own blinders...
FineStructureConstant
5 / 5 (8) Oct 22, 2016
Nobody in their wildest fantasies - except possibly EU camp-followers - would suggest that volcanoes move, on Io or anywhere else. But considering the tremendous amount of tidal heating to which Io is subjected - due to its' not only being so close to Jupiter, but also due in main to it's orbital eccentricity - volcanoes are a certainty on Io.

Very good evidence exists to indicate that a magma ocean some 50km deep underlies the surface. For volcanoes to appear or reappear at various places, there only need to be cracks, fractures, fissures or fault lines which extend to considerable distances, or magma hot spots which punch through the surface from time to time. Volcanoes can then appear anywhere along such features.

The morphology of the mountains on Io indicate that local cracking and upheaval of the surface occurs over the whole surface. And, although the Ionian mountains are not themselves volcanoes, yet volcanoes are often seen at the edges of the upraised material.
FineStructureConstant
5 / 5 (8) Oct 22, 2016
The surface of Io displays very few impact crater sites, indicating that the surface is continually being reworked. Many large volcanic paterae exist on the surface, with clear evidence of lava flows or of lava lakes.

Spectral analysis of the surface show extensive sulfur and sulfur dioxide fields, basalt silicate lava fields, and actively-moving, glowing lava flows having been imaged (Tvashtar Paterae).

Plumes of material ejected by explosive volcanism reach heights up to 300km above the surface - a short video exists (https://en.wikipe...deo.gif) showing one plume being ejected by Tvashtar Paterae over the course of eight minutes. It should be noted that NO evidence of electrical discharges can be observed during the ongoing event.

In short, there is an overwhelming body of evidence for active volcanoes on Io.
FineStructureConstant
5 / 5 (8) Oct 22, 2016

On the other hand, NO data supports the idea that electrical discharges might be responsible for plumes, or for paterae, or active lava flows or spectroscopic features. None.

Further, there is no known mechanism - and certainly none provided by the EU's "theoretical wing" - whereby electrical discharges could repeatedly return to the same spot to induce continued "melting of the surface" (read lava flows), nor to produce plumes emanating from such stationary hot-spots (read volcanoes). Neither is there any evidence of the fields of glass which would be produced by such discharges striking the surface.

As for electrical discharges meandering across the surface in a vain attempt to explain "moving volcanoes", there are no visible tracks anywhere on the surface to indicate the passage of such vast discharges as the EU claim to be responsible for the visible surface features.
FineStructureConstant
5 / 5 (8) Oct 22, 2016
In a similar, and depressingly familiar, manner, the EU provide no mechanisms or workable scenarios, and no numerical analyses, to explain how such discharges might originate or be created.

To sum up, we see in the EU's unsupported claims the same old crackpot, delusional, no-numbers, no-evidence, no-thought, zero ingenuity, utter lack of scientific integrity that we have come to expect of them. Epic fail: again!
FineStructureConstant
5 / 5 (7) Oct 22, 2016
@cantTieHisOwnShoelaces
"The distribution of the eruptions is a poor match to the model predictions"
Typical cherry-picking by cd and his fellow one-handed Electric Ukulele players in a misguided attempt to garner favor for their crackpot "ideas".

Here's the whole quote again:
"The distribution of the eruptions is a poor match to the model predictions," de Kleer said, "but future observations will tell us whether this is just because the sample size is too small, or because the models are too simplified. Or perhaps we'll learn that local geological factors play a much greater role in determining where and when the volcanoes erupt than the physics of tidal heating do."
So - as always in real science - it's more complicated than first impressions might suggest. Future observations will help scientists (i.e. those among us who are clever enough to build and operate spacecraft or large observatories) to develop models and methods to better understand such phenomena.
cantdrive85
1.8 / 5 (5) Oct 22, 2016
"It is the theory which decides what we can observe."
— Albert Einstein

Obviously lost on the Constant Bother. Let's read a bit further into my "cherry picking";

Io's intense volcanic activity is powered by tidal heating

Note: Stated as fact, science be damned. It continues;
Models for how this heating occurs predict that most of Io's total volcanic power should be emitted either near the poles or near the equator, depending on the model,

So regardless which of the models are used, none agree with observation.
and that the pattern should be symmetric between the forward- and backward-facing hemispheres in Io's orbit

And what was observed?
That's not what they saw.

Oops...
Though they saw a surprising number of short-lived but intense eruptions that appeared suddenly and subsided in a matter of days, every single one took place on the trailing face of Io.

Solution? Blame on that which can't be seen or falsified, magma ocean. Bingo!
cantdrive85
1.8 / 5 (5) Oct 22, 2016
One key target of interest was Io's most powerful persistent volcano, Loki Patera, which brightens by more than a factor of 10 every 1-2 years.

By a factor of 10 every 1-2 years... And what would be the tidal heating explanation?
FineStructureConstant
5 / 5 (5) Oct 22, 2016
Dormant, then active.
Dormant, then active.
Back and to the left...

A grain of commonsense is required. A little too much for you to handle, I know.
FineStructureConstant
5 / 5 (6) Oct 22, 2016
...that which can't be seen or falsified, magma ocean
Well, there are plenty of sources on this very subject - either online or referenced online, just waiting for you to click on them.

From the Wiki Io page,
The Jovian magnetic field lines that do get past Io's ionosphere also induce an electric current, which in turn creates an induced magnetic field within Io's interior. Io's induced magnetic field is thought to be generated within a partially molten, silicate magma ocean 50 kilometers beneath Io's surface
and further down
analysis of Galileo magnetometer data in 2009 revealed the presence of an induced magnetic field at Io, requiring a magma ocean 50 km (31 mi) below the surface. Further analysis published in 2011 provided direct evidence of such an ocean
So evidence for a subsurface magma ocean comes in the shape of Jovian magnetic fields, induced electric currents and induced magnetic fields - I'd have thought that would be right up your street.
FineStructureConstant
5 / 5 (6) Oct 22, 2016
@cd - Here, I know it's too much to ask of you to find it yourself, so here's an article in ApJ (as astrophysicists like to call it ;-) ) entitled "TIDAL HEATING IN A MAGMA OCEAN WITHIN JUPITER'S MOON Io":

http://iopscience....iop.org

In their conclusions to the paper (which is free to read), the authors state
Io is perhaps the best example available for study of a planetary body under extreme tidal heating. The tidal response of Io is highly significant in the moon's internal dynamics and structure as well as its orbit and rotation. Study of this tidal response is of specific relevance to Io but is also clearly relevant to the general study of solar- and extra-solar planetary systems.
Note that: "extreme tidal heating"...
FineStructureConstant
5 / 5 (6) Oct 22, 2016
And then again, it appears I may have been in error in stating that the volcanoes on Io could not move. If, as now seems likely, the subsurface magma ocean does indeed exist, then the observed eastward shift of volcanoes from their predicted positions - positions based on a model of Io as being composed of a deformable solid - could best be explained by a different model: one that had to do with the interaction between heat produced by fluid flow and heat from solid-body tides.

So
a combination of fluid and solid tidal heating effects may best explain all the volcanic activity observed on Io. "The fluid tidal heating component of a hybrid model best explains the equatorial preference of volcanic activity and the eastward shift in volcano concentrations, while simultaneous solid-body tidal heating in the deep-mantle could explain the existence of volcanoes at high latitudes.(http://www.nasa.g...o-tides)
Fluid. Tidal. Heating.
Phys1
5 / 5 (3) Oct 22, 2016
Whatever was observed, it does not support anything that CD85 says.
Captain Stumpy
4.3 / 5 (6) Oct 22, 2016
Note: Stated as fact, science be damned
@cantread
1- note: it's a f*cking article on a pop-sci news aggregate appealing to a broad audience

but then again, considering you can't tell the difference between colourful language in articles and technical details in studies, this is no surprise

2- if you will take the time to actually read the science (like the study posted by FSC) then you will notice that there is evidence to support tidal heating

but then again, that would require you to give up your religious proselytizing for the eu because you would then learn of the fallacies of your own cult

http://phys.org/n...mes.html

if you were such a true believer in your pseudoscience, you would visit a shaman for your next surgery (apparently you already visited a mechanic for your lobotomy, considering the level of your education demonstrated in your posts)
FineStructureConstant
5 / 5 (5) Oct 23, 2016
apparently you already visited a mechanic for your lobotomy
That's naughty, Cap! ...but nice ;-)

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