At the solar system's edge, more surprises from Voyager

Jun 27, 2013
Artist's concept of NASA's Voyager spacecraft. Credit: NASA/JPL-Caltech

(Phys.org) —Data from NASA's Voyager 1 spacecraft continues to provide new insight on the outskirts of our solar system, a frontier thought to be the last that Voyager will cross before becoming the first man-made object to reach interstellar space.

In papers published this week in the journal Science, scientists from the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., and other Voyager partner institutions provide more clarity on the region they named the "magnetic highway" in December 2012. Cruising through what scientists describe as a curious, unexpected charged-particle environment, Voyager has detected, for the first time, low-energy , now that particles of the same energy from inside the bubble around our Sun disappeared. As a result, Voyager now sees the highest level so far of particles from outside our solar bubble that originate from the death of other .

"Voyager 1 may be months or years from leaving the solar system—we just don't know," says APL's Stamatios Krimigis, principal investigator for Voyager's Low-Energy Charged Particle (LECP) instrument. "But the wait itself is incredibly exciting, since Voyager continues to defy predictions and change the way we think about this mysterious and wonderful gateway region to the galaxy."

This artist's concept shows NASA's Voyager 1 spacecraft exploring a region called the "depletion region" or "magnetic highway" at the outer limits of our heliosphere, the bubble the sun blows around itself. In this region, the magnetic field lines generated by our sun (yellow arcs) are piling up and intensifying and low-energy charged particles that are accelerated in the heliosphere's turbulent outer later (green dots) have disappeared. Scientists think the depletion region is the last region Voyager 1 has to cross before reaching interstellar space, which is the space between stars, Voyager 1 passed a shockwave known as the termination shock in 2004, where solar wind suddenly slowed down and became turbulent. In 2010, it then passed into an area called the "stagnation region" where the outward velocity of the solar wind slowed to zero and sporadically reversed direction. In the slow-down and stagnation regions, the prevalence of low-energy charged particles from our heliosphere jumped dramatically and is indicated by the green dots. On Aug. 25, 2012. Voyager 1 entered the depletion or magnetic highway region, where the magnetic field acts as a kind of "magnetic highway" allowing energetic ions from inside the heliosphere to escape out, and cosmic rays from interstellar space zoom in. Magnetic field lines form a spiral around the solar system because of the rotation of the sun, and at the edge of the heliosphere they form roughly parallel arcs. Because an interstellar wind outside is pushing back on the heliosphere, magnetic field lines pile up as the solar wind slows, like cars back up at a freeway off-ramp. The compression of field lines increases the strength of the magnetic field as Voyager approaches interstellar space. Since scientists don't know the exact location of the heliopause - which is the border to interstellar space - that area has been labeled with a question mark. Image credit: NASA/JPL-Caltech

Voyager 1 and 2 were launched in 1977 and between them visited Jupiter, Saturn, Uranus and Neptune. Since 1990, the twin spacecraft have been on their Interstellar Mission, on track to leave the , which is the bubble of magnetic field and charged particles the Sun blows around itself. On Aug. 25, 2012, when Voyager 1 was about 11 billion miles (18 billion kilometers) from the Sun, the spacecraft reached the so-called magnetic highway where charged particles from inside the heliosphere zoomed out along the magnetic field as cosmic rays from far outside zoomed in. The lack of a detectable change in the direction of that magnetic field, however, convinced scientists that Voyager remained within the Sun's influence.

The new Science papers focus on observations from the summer and fall of 2012 by LECP as well as Voyager 1's Cosmic Ray and Magnetometer instruments, with additional LECP data through April 2013.

"The most dramatic part was how quickly the solar-originating particles disappeared; they decreased in intensity by more than 1,000 times, as if there was a huge vacuum pump at the entrance ramp onto the magnetic highway," says Krimigis. "We have never witnessed such a decrease before, except when Voyager 1 exited the giant magnetosphere of Jupiter, some 34 years ago."

"Surprisingly, the traveling direction of the 'inside' charged particles in this region made a difference, with those moving straightest along the magnetic field lines decreasing most quickly. Those that moved perpendicular to the did not change as quickly," adds LECP Co-investigator Robert Decker, also of APL. The cosmic rays from outside, moving along the field lines, were somewhat more intense than those moving perpendicular to the field, and this imbalance varied significantly with time during the eight months since "It is this time-varying behavior of the that tells us that we're still in a region controlled by our Sun," says APL's Edmond Roelof, also an LECP co-investigator.

The multidimensional measurements speak to the unique abilities of the LECP detector, designed at APL in the 1970s. It includes a stepper motor that rotates the instrument through 45-degree steps every 192 seconds, allowing it to gather data in all directions and pick up something as dynamic as the solar wind and galactic particles. The device, designed and tested to work for 500,000 steps and last four years, has been working for nearly 36 years and well past 6 million steps.

Voyager 1 is 11.6 billion miles (18.6 billion kilometers) from the Sun, poised to become Earth's first robotic ambassador to the space between the stars. At 9.4 billion miles (15.1 billion kilometers), Voyager 2 has seen some gradual changes in the , yet scientists do not think Voyager 2 has reached the magnetic highway.

Explore further: Bad weather delays Japan asteroid probe lift off

More information: References:

* "Magnetic Field Observations as Voyager 1 Entered the Heliosheath Depletion Region," L. F. Burlaga, N. F. Ness, and E. C. Stone, Science, DOI: 10.1126/science.1235451; www.sciencemag.org/content/ear… nce.1235451.abstract
* "Search for the Exit: Voyager 1 at Heliosphere's Border with the Galaxy," S. M. Krimigis, R. B. Decker, E. C. Roelof, M. E. Hill, T. P. Armstrong, G. Gloeckler, D. C. Hamilton, and L. J. Lanzerotti, Science, DOI:10.1126/science.1235721; www.sciencemag.org/content/ear… nce.1235721.abstract
* "Voyager 1 Observes Low-Energy Galactic Cosmic Rays in a Region Depleted of Heliospheric Ions," E. C. Stone, A. C. Cummings, F. B. McDonald, B. C. Heikkila, N. Lal, and W. R. Webber, Science, DOI:10.1126/science.1236408; www.sciencemag.org/content/ear… nce.1236408.abstract

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cantdrive85
1.2 / 5 (21) Jun 27, 2013
Cruising through what scientists describe as a curious, unexpected charged-particle environment,


Yep, curious and unexpected, as is just about every observation.

"But the wait itself is incredibly exciting, since Voyager continues to defy predictions and change the way we think about this mysterious and wonderful gateway region to the galaxy."

Huh, the theory isn't confirmed by predictions? Well, it's not a problem experienced by Electric Sun proponents, actually the data matches the predictions.

http://electric-c...2012.pdf
Moebius
2.3 / 5 (6) Jun 28, 2013
Maybe first contact criteria isn't warp drive but getting something out of the solar system.
Fleetfoot
4.3 / 5 (3) Jun 28, 2013
Maybe first contact criteria isn't warp drive but getting something out of the solar system.


How would they detect it, the signal is a tight beam back towards Earth.

First contact criteria is ... we have to go visit them.
Fleetfoot
5 / 5 (9) Jun 28, 2013
it's not a problem experienced by Electric Sun proponents


Wrong again, this is a serious problem for the cranks. Your paper describes what happens when a current is passed through a low density gas. If you consider a plane perpendicular to the axis of the tube at any point along its length, the current flowing through the plane must be the same. Current is a net flow of charge but what has been observed is that the flow goes to zero, no charged particles, no current. Of course that isn't a problem for real science because the solar wind is actually a flow of both protons and electrons, i.e. a flow of neutral, ionised gas. It is the reduction in the degree of ionisation that is the surprise.

actually the data matches the predictions.

http://electric-c...2012.pdf


Nothing in that paper even talks about the current flow or the depletion region which is observed, and it was written AFTER the discovery of the stagnation region, no prediction there.
panorama
3 / 5 (1) Jun 28, 2013
Does anyone know if there are plans for a satellite that will be dedicated to studying this region and beyond? As in something in the works with better detectors/sensors than V-ger1?
panorama
5 / 5 (2) Jun 28, 2013
Never mind, it looks like that's what's planned for New Horizons after it is done in the Kuiper Belt, http://en.wikiped...on_dates
HannesAlfven
1 / 5 (10) Jun 29, 2013
Re: "Wrong again, this is a serious problem for the cranks ..."

Contrast that opinion with the following, from the Wired Magazine article at http://www.wired....-region/ on these same observations ...

"For his part, Krimigis didn't even want to speculate on what Voyager might encounter next because theorists' models have so far not worked extremely well."

Re: "what has been observed is that the flow goes to zero, no charged particles, no current."

Again, from the Wired article:

"if the solar wind was completely gone, galactic cosmic rays should be streaming in from all directions. Instead, Voyager found them coming preferentially from one direction."

With additional quotes ...

"No one is entirely sure what's going on."

... and ...

"It's a huge surprise"

It seems that the physorg article has been stripped of all of the "fizz".
HannesAlfven
1 / 5 (9) Jun 29, 2013
Probably the best resource to keep an eye out on this controversy is on Wal Thornhill's site at http://www.holosc...rified/. If you scroll down that page a ways to the diagram titled "The Sun's Environment", you'll see a geometrical depiction for how Wal believes that the solar system fits into the larger cosmic plasma picture. Notice the column of current which runs preferentially through the solar system.

Fight it all you want, guys, but to be clear, we are not "cranks" for simply entertaining the notion that the solar system is electrically connected to other parts of the galaxy. It's been readily apparent that the interstellar "clouds" are not all that cloud-like since the work of Gerrit Verschuur, almost 25 years ago! Please learn what a critical ionization velocity is, and then look up the various papers where Verschuur identifies them to be associated with the knots of interstellar filaments.
HannesAlfven
1 / 5 (9) Jun 29, 2013
Note that Wal's diagram also explains the ENA ribbon, which was also a mystery to conventional theorists. From that article:

--

Researchers had expected gusts in the solar wind blowing against the boundary to create 20% or 30% variations in ENA emissions, but the ribbon is 10 times that intense—a narrow band blazing across the sky like some Milky Way on fire. Charged particles have apparently become bunched along the ribbon near the boundary, says McComas, but how they got there "is still a big mystery. Our previous ideas about the outer heliosphere are going to have to be revised." "I'm blown away completely," says space physicist Neil Murphy of NASA's Jet Propulsion Laboratory in Pasadena, California. "It's amazing, it's opened up a new kind of astronomy."

--

People should of course debate the meaning of the observations, but those who pretend that there are no mysteries here for conventional theory are kidding themselves. What complicates things is that plasmas are complex.
HannesAlfven
1 / 5 (9) Jun 29, 2013
I understand why people react the way they do to ideas that undermine their worldviews. The stability of our worldviews is part of what keeps us sane. When somebody threatens that worldview with a new or disruptive idea, it only makes sense that it will tend to be treated as a personal attack.

But, I think the broader context for what Wal is attempting to do needs to be taken into consideration: He -- like many others -- continues to believe that many of the existing enigmas of science can be explained with classical theories. What I want to warn people against is the knee-jerk tendency we commonly see when people shout down others for their attempts to propose mundane, classical, laboratory-derived inferences for cosmic enigmas. If the conventional astrophysicists have decided to cast certain assumptions and hypotheses into stone, then it becomes the place of "outsider theorists" to provide us with alternatives.

Science needs outsiders when assumptions are treated as facts.
cantdrive85
1 / 5 (11) Jun 29, 2013
Of course that isn't a problem for real science because the solar wind is actually a flow of both protons and electrons, i.e. a flow of neutral, ionised gas.


Alfven described it as quasi-neutral, so it may not be a problem for the theoretical POV as it is ignored, but is is in fact a problem being that is not (a flow of neutral, ionised gas) what is observed. I like the last quote from the Wired article HA linked above;

"I'm convinced that nature is far more imaginative than we are," he (physicist Ed Stone of Caltech) said.

Apparently his opinion isn't shared by those who feel this is a settled science, while at the same time being surprised by every observation.
Fleetfoot
5 / 5 (4) Jun 30, 2013
Re: "Wrong again, this is a serious problem for the cranks ..."

Contrast that opinion with the following, from the Wired Magazine article at http://www.wired....-region/ on these same observations ...

...

Re: "what has been observed is that the flow goes to zero, no charged particles, no current."

Again, from the Wired article:

"if the solar wind was completely gone, ...


Better, compare my comment with the preceding paragraph:

"Then, about a year ago, everything got really quiet around the probe. Voyager 1's instruments indicated at the solar wind suddenly dropped by a factor of 1,000, to the point where it was virtually undetectable."

It's true that our present simplistic models need a lot of work but the EU version fares far worse as I said.
Fleetfoot
5 / 5 (6) Jun 30, 2013
Probably the best resource to keep an eye out on this controversy is on Wal Thornhill's site at http://www.holosc...rified/.


"IBEX has discovered that the heliosheath is dominated not by the Sun but by the Galaxy's magnetic field. Since the galaxy's magnetic field traces the direction of interstellar electric current flow in space near the Sun, it is a result that conforms to the EU model of galaxies and stars."

Compare that with the Wired article:

http://www.wired....-region/

"Furthermore, even though the solar particles had dropped off, the probe hasn't measured any real change in the magnetic fields around it. That's hard to explain because the galaxy's magnetic field is thought to be inclined 60 degrees from the sun's field."

That's the sentence after the one you quoted. The actual observation is the opposite of what the site claims as support for your model. A nice bit of crank "selective quoting".
Fleetfoot
5 / 5 (6) Jun 30, 2013
Probably the best resource to keep an eye out on this controversy is on Wal Thornhill's site at http://www.holosc...rified/. ... Fight it all you want, guys, but to be clear, we are not "cranks" for simply entertaining the notion that the solar system is electrically connected to other parts of the galaxy. ..


Cantdrive is fond of quoting Perratt on this subject. This is from his site:

"The Plasma Universe and Plasma Cosmology have no ties to the anti-science blogsites of the holoscience 'electric universe'."

http://www.plasma...se.info/
Fleetfoot
5 / 5 (7) Jun 30, 2013
I understand why people react the way they do to ideas that undermine their worldviews. .. When somebody threatens that worldview with a new or disruptive idea, it only makes sense that it will tend to be treated as a personal attack.


That this is complete rubbish can be seen for what has been perhaps one of the most significant changes in cosmology since the discovery of the Hubble Law. Einstein called the Cosmological Constant his "biggest blunder" and virtually every textbook written in the 20th century either ignored it or noted it as a theoretical term which had a value of zero. In 1998 Perlmutter published observational data which suggested that in fact the CC was non zero and equivalent to a higher energy density than everything else put together.

Was he subjected to "personal attack"? No, instead, his team was awarded the Nobel Prize for the discovery and consequent paradigm shift.

EU is criticised because it is "anti-science" as Perratt put it, that's not personal.
Fleetfoot
5 / 5 (5) Jun 30, 2013
Of course that isn't a problem for real science because the solar wind is actually a flow of both protons and electrons, i.e. a flow of neutral, ionised gas.


Alfven described it as quasi-neutral, so it may not be a problem for the theoretical POV as it is ignored, but is is in fact a problem being that is not (a flow of neutral, ionised gas) what is observed.


Alfven invented the term "quasi-neutral" specifically to describe a flow of neutral, ionised gas. Principally, craft are built to detect only the more massive positive ions, but some craft can measure the electron flow. For example see this article:

http://solarphysi...su5.html

A "quasi-neutral" flow is what is observed.

Apparently his opinion isn't shared by those who feel this is a settled science, ..


Only the EU cranks seem to think this is "settled science" or "anti-science" as Perratt put it.
cantdrive85
1 / 5 (9) Jun 30, 2013
Neutral implies that a current can not flow through it, that's why Alfven suggested the term "quasi-neutral" because currents very definitely flow through plasma.

The reason they are "anti-science" is due to responses from supposedly scientific individuals such as your self, casting aside possibilities based on false presumptions. Perratt claims no affiliation with the EUT, this is true yet much of the science of the EUT is based upon Alfven's Plasma Cosmology. The true irony is that Peratt has produced a number of peer-reviewed papers along side the members of the EU team.

BTW, no "paradigm shift" there, just a misuse and misinterpretation of the data to further support the "theoretical paradigm" in lieu of real laboratory based science.
cantdrive85
1 / 5 (11) Jun 30, 2013

Alfven invented the term "quasi-neutral" specifically to describe a flow of neutral, ionised gas. Principally, craft are built to detect only the more massive positive ions, but some craft can measure the electron flow. For example see this article:

http://solarphysi...su5.html

A "quasi-neutral" flow is what is observed.


A bunch of pseudo-science claptrap at that website. "Open field lines", less important because of their smaller mass"? Yep, pseudo-science claptrap.

What about the solar wind and those electrons? Here is an electrical engineers POV in re of the data. Once again, support for the electric model is undeniable.
http://electric-c...Wind.pdf
http://electric-c...2013.pdf
Maggnus
5 / 5 (6) Jun 30, 2013
Well actually can'tdrive, support for the electric model is not there. In fact, to say there is no support for the model in your postings is not even correct; they are talking about something completely different. SO not just not even in the same ballpark, not even in the same county.

The psuedo-science is a "theory" that basis its tenants on an interpretation of a picture painted on a cave. It's fun to speculate about fantastical explanations for such, but that is most assuredly NOT science.
Fleetfoot
5 / 5 (6) Jun 30, 2013
Neutral implies that a current can not flow through it,


Rubbish. A piece of metal in your hand is neutral but a very good conductor.

that's why Alfven suggested the term "quasi-neutral" because currents very definitely flow through plasma.

Nope, plasma is conductive but "quasi-neutral" means it carries no net charge, the number of positive and negative charges in the flow are equal. The papers you keep citing all assume that there is a net current contrary to what Alfven said. You need to learn some very basic electrical circuit theory if you don't understand that.

The reason they are "anti-science" is due to responses from supposedly scientific individuals such as your self, .


Read the site, Perratt says the 'holoscience' nonsense is "anti-science", he's not talking about people.
Fleetfoot
5 / 5 (6) Jun 30, 2013
A bunch of pseudo-science claptrap at that website. "Open field lines"


"mostly anchored in coronal holes"

"less important because of their smaller mass"?


The full quote is:

"Because of their small masses, electrons are less important than ions for the solar wind dynamics".

This is obvious since the kinetic energy is proportional to the mass for any given speed.

Yep, pseudo-science claptrap.


To you perhaps, basic Newtonian mechanics to the rest of us. If you try to criticise a site but selectively snipping the text, you only make yourself look as though you can't understand what is actually written. Even the papers you quote say the same thing.

Fleetfoot
5 / 5 (4) Jun 30, 2013
What about the solar wind and those electrons? Here is an electrical engineers POV in re of the data. Once again, support for the electric model is undeniable.


The paper rambles on for pages but the bottom line can be summed up in this comment from his summary:

"A proton (a positive single electronic charge) in a collisionless environment can be accelerated from rest to a velocity of 730 km/s by giving it 4.46 x 10^-16 Joules of kinetic energy. This is equivalent to ~2780 eV (allowing it to fall through a voltage drop of 2780V)."

The problem is that the same field would also accelerate the electrons but in the opposite direction, back towards the Sun. Since the proton/electron mass ratio is 1836 and the energy imparted depends only on the voltage, the electrons' speed change would be higher by 42.8 times, i.e. 31280km/s. None could leave the charge region so the charge would immediately be neutralised. This idiot has forgotten that an isolated sphere is a capacitor!
Protoplasmix
3 / 5 (4) Jul 01, 2013
It sounds like the EU theory makes predictions of anisotropy in incident radiation hitting the planet -- which aren't supported by observations of GRBs or high energy cosmic rays, and aren't supported by observations of SNe (especially when taken together with data from neutrino detectors), and aren't supported by observations of the CMBR. So I looked for an EU equation of state to see what predictions it makes but I couldn't find one. @CD85 or HA, is there an EU equation of state?
Fleetfoot
5 / 5 (5) Jul 01, 2013
It sounds like the EU theory makes predictions of anisotropy in incident radiation hitting the planet -- which aren't supported by observations of GRBs or high energy cosmic rays, and aren't supported by observations of SNe (especially when taken together with data from neutrino detectors), and aren't supported by observations of the CMBR. So I looked for an EU equation of state to see what predictions it makes but I couldn't find one. @CD85 or HA, is there an EU equation of state?


I don't think it's that simple. One of the papers CD cited predicts the solar wind is moving towards the Sun on one side and away on the other. The other has an isotropic wind but violates Coulombs Law by then having a constant current flow out of a capacitor (the Sun) but without a change in potential. I don't think there is a single model, just random ideas from which you can pick-and-mix.
Protoplasmix
5 / 5 (3) Jul 01, 2013
I don't think it's that simple...

I suppose not. One EU website seemed to suggest application of MHD and Kirchhoff's circuit laws should suffice. It said the science that predicted things like gravitational lensing and frame dragging isn't necessary to explain things like black holes, neutron stars, or the big bang. Of course stating that and showing it are two different things.

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