Pluto's interactions with the solar wind are unique, study finds

May 4, 2016
Using data from an instrument aboard the New Horizons spacecraft gathered on its Pluto flyby in July 2015, scientists have observed the material coming off of Pluto and seen how it interacts with the solar wind. This figure shows the size scale of Pluto’s interaction with the solar wind derived from the data. The bow shock is indicated by the extension of the locations where the study’s authors measured the light, solar wind ions to be about 20 percent slowed down from the upstream solar wind speed. The Plutopause (purple) is a finite-sized boundary layer ~0.9 Pluto radii thick at the nose and separates the solar wind (blue) from the heavy ion tail (red). Even though the heavy ion tail extends back more than 100 Pluto radii at the time of the New Horizons flyby, the upstream interaction is very compact and the bow shock is almost compressed onto the obstacle. Credit: American Geophysical Union. 

Pluto has some characteristics less like that of a comet and more like much larger planets, according to an analysis of Pluto's unique interaction with the solar wind, scientists say.

Using data from an instrument aboard the New Horizons spacecraft gathered on its Pluto flyby in July 2015, scientists have observed the material coming off of Pluto and seen how it interacts with the solar wind, and found it completely new – and unexpected.

"This is a type of interaction we've never seen before anywhere in our solar system," said David J. McComas, lead author of the new study published today in the Journal of Geophysical ResearchSpace Physics, a publication of the American Geophysical Union.

McComas, professor in Princeton University's Department of Astrophysical Sciences and vice president for the Princeton Plasma Physics Laboratory, leads the Solar Wind Around Pluto (SWAP) instrument aboard New Horizons; he also led development of SWAP when he was at the Southwest Research Institute (SwRI) in Texas. The research was funded as a part of the New Horizons project by NASA.

Space physicists say that they now have a treasure trove of information about how Pluto's atmosphere interacts with the solar wind. Solar wind is the plasma, or charged particles, that spews off from the sun into the solar system at a supersonic 400 kilometers per second (1 million miles per hour), bathing planets, asteroids, comets and interplanetary space in a soup of mostly electrons and protons.

"The results are astonishing. We were fascinated and surprised" by the findings, McComas said.

Previously, most researchers thought that Pluto was characterized more like a comet, which has a large region of gentle slowing of the solar wind, as opposed to the abrupt diversion solar wind encounters at a planet like Mars or Venus. Instead, like a car that's part gas- and part battery-powered, Pluto is a hybrid, the researchers say.

"This is an intermediate interaction, a completely new type. It's not comet-like, and it's not planet-like. It's in-between," McComas said. "We've now visited all nine of the classical planets and examined all their solar wind interactions, and we've never seen anything like this."

Schematic diagram of Pluto’s interaction with the solar wind as inferred from SWAP observations along the trajectory of the New Horizons flyby. New Horizons crossed the Sun-Pluto line from the dawn/southern portion of the tail (dashed portion of trajectory) into the dusk/northern (solid portion of the trajectory in the cutaway) at ~44 Pluto radii down tail. Portions of the trajectory inside the heavy ion tail behind Pluto are indicated in red and light ion sheath that surrounds the tail are in blue. The bow shock observed near Pluto has dissipated into just a bow wave by the distance back that New Horizons exited through it. Credit: American Geophysical Union.

"These results speak to the power of exploration. Once again we've gone to a new kind of place and found ourselves discovering entirely new kinds of expressions in nature," said Alan Stern, New Horizons principal investigator at the Southwest Research Institute. "Many people were surprised by Pluto's complex geology and atmosphere. This paper shows there's even more that's surprising there, including its atmosphere-solar wind interaction."

Pluto continues to confound. Since it's so far from the sun – an average of about 5.9 billion kilometers (3.7 billion miles) – and because it's so small, scientists thought Pluto's gravity would not be strong enough to hold in its extended atmosphere. But, "Pluto's gravity clearly is enough to keep material sufficiently confined," McComas said.

Further, the scientists found that very little of Pluto's atmosphere is comprised of neutral particles converted to electrically charged ions and swept out into space.

"This is backwards for many other planets, where the neutral particles stay relatively close to the planet," said Michael Liemohn, a University of Michigan astrophysicist and Editor-in-Chief of JGR-Space Physics, who was not involved with the research but who helped edit the paper. "An ion particle becomes influenced by the electric and magnetic forces present in the solar system, which can be a very efficient acceleration processes. But at Pluto, McComas et al found that only a wisp of atmosphere leaves the planet as ions."

The researchers were able to separate the heavy ions of methane, the main gas escaping from Pluto's atmosphere, from the light ions of hydrogen that come from the sun using the SWAP instrument.

Among their Pluto findings:

  • Like Earth, Pluto has a long ion tail, that extends downwind at least a distance of about 100 Pluto radii (119,000 kilometers (73,800 miles), almost three times the circumference of Earth), loaded with heavy ions from the atmosphere and with "considerable structure;"
  • Pluto's obstruction of the solar wind upwind of the planet is smaller than had been thought. The solar wind isn't blocked until about the distance of a couple planetary radii (2,968 kilometers (1,844 miles), about the distance between Chicago and Los Angeles);
  • Pluto has a very thin "Plutopause" – or boundary of Pluto's tail of heavy ions and the sheath of the shocked solar wind that presents an obstacle to its flow.

The scientists write: "Pluto interaction with the solar wind appears to be a hybrid with the bow shock generated by mass-loading like at a comet, but the obstacle to the solar wind flow – the Plutopause – sustained by atmospheric thermal pressure as at Venus and Mars."

Heather Elliott, astrophysicist at Southwest Research Institute and co-author on the paper, said that the study provides interesting comparisons. "Comparing the solar wind-Pluto interaction to the solar wind-interaction for other planets and bodies is interesting because the physical conditions are different for each, and the dominant physical processes depend on those conditions," Elliott said.

What is significant, McComas said, is the range of diversity that bodies in the solar system have with the solar wind. Further, the findings offer clues to the magnetized plasmas that one might find around other stars. "The range of interaction with the solar wind is quite diverse, and this gives some comparison to help us better understand the connections in and beyond our solar system," McComas said.

The scientists conclude: "The SWAP data will … be reanalyzed … for many years to come as the community collectively grapples with Pluto's unique interaction – one that is unlike that at any other body in the ."

New Horizons is the first mission in NASA's New Frontiers program, managed by the agency's Marshall Space Flight Center in Huntsville, Ala. The Johns Hopkins University Applied Physics Laboratory designed, built, and operates the New Horizons spacecraft and manages the mission under Principal Investigator Dr. Alan Stern's direction for NASA's Science Mission Directorate. SwRI leads the science mission, payload operations, and encounter science planning. The NASA Heliophysics program also supported the analysis of these observations.

Explore further: Multitasking New Horizons observed solar wind changes on journey to Pluto

More information: "Pluto's Interaction with the Solar Wind," D. J. McComas et al. , 2016, Journal of Geophysical Research - Space Physics, onlinelibrary.wiley.com/doi/10 … 016JA022599/abstract

Related Stories

Pluto's haze varies in brightness

April 19, 2016

Scientists on NASA's New Horizons mission team are learning more about the structure and behavior of Pluto's complex atmosphere by discovering new attributes of its extensive haze layers. The hazes were first discovered by ...

New Horizons imagery reveals small, frozen lake on Pluto

March 28, 2016

NASA's New Horizons spacecraft spied several features on Pluto that offer evidence of a time millions or billions of years ago when – thanks to much higher pressure in Pluto's atmosphere and warmer conditions on the surface ...

Recommended for you

NASA telescope studies quirky comet 45P

November 22, 2017

When comet 45P zipped past Earth early in 2017, researchers observing from NASA's Infrared Telescope Facility, or IRTF, in Hawai'i gave the long-time trekker a thorough astronomical checkup. The results help fill in crucial ...

Cassini image mosaic: A farewell to Saturn

November 21, 2017

In a fitting farewell to the planet that had been its home for over 13 years, the Cassini spacecraft took one last, lingering look at Saturn and its splendid rings during the final leg of its journey and snapped a series ...

Uncovering the origins of galaxies' halos

November 21, 2017

Using the Subaru Telescope atop Maunakea, researchers have identified 11 dwarf galaxies and two star-containing halos in the outer region of a large spiral galaxy 25 million light-years away from Earth. The findings, published ...

60 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

cantdrive85
1.7 / 5 (23) May 04, 2016
Surprise, surprise, surprise... Measurements don't agree with theory, just like every other aspect of space plasmas starting from day one of man's endeavours of space exploration.
Maggnus
4.7 / 5 (25) May 04, 2016
Surprise surprise surprise, an Acolyte misunderstands how science and discovery works.
wduckss
1.7 / 5 (23) May 05, 2016
Surprise surprise surprise, an Acolyte misunderstands how science and discovery works.


Science rests on empty stories and fairy tales and it is not surprising that we have surprise, surprise ...
Phys1
4.4 / 5 (19) May 05, 2016
Duckass where do you get this stuff.
jim_xanara
3.6 / 5 (20) May 05, 2016
He's a troll, full stop. I thought we weren't supposed to blithely feed the trolls. I say you tell his ilk- the kind that have zero interest in the topics, just want to spew "science is a fairy story!"- to get off in the rudest possible terms, or say nothing. Gratuitously feeding them like that, imho, is as bad as the post itself.
chileastro
3.5 / 5 (19) May 05, 2016
"Plutopause". Hmmm. Shouldn't that be "Pluto Paws"?

Re: the trolls PO have doubled down on their promoting trolling. Last week we saw them delete an account for the generic statement that someone would love the chance to dance on the trolls' grave, yet trolls get seldom get accounts deleted for saying racist, personally threatening, slanderous statements, and just pure misinformation. Can anyone remember one having an account deleted for just one deleted post? It certainly wasn't up to the level of what the trolls do every day with impunity from the mods, so one can only conclude that they're running a little troll farm. I say we take serious discussion to the forum, which is moderated, and teach them which side their bread is buttered on by posting no comments on the articles. Let it be total troll spew and pretty clear what an embarrassment it all is.
FineStructureConstant
4.8 / 5 (21) May 05, 2016
Surprise, surprise, surprise
no surprises that the self-appointed expert in plasmas, the EU sewer-rat @cantgetitright gets it wrong. Again: this is really getting old...
Measurements don't agree with theory
there was no "theory", just general expectations, which were confounded by new evidence. Evidence collected by an instrument which was specifically built and flown on New Horizons to make just the kind of surprising measurements which were returned.

D'you see: the scientists behind this endeavour were HOPING to find something new and unexpected, and they did. If they hadn't wanted their precious "mainstream theories" to be called into question, they wouldn't have gone to all that trouble. Exploration, discovery, surprise: that's the name of science.
just like every other aspect of space plasmas starting from day one of man's endeavours of space exploration
You bozos are firmly excluded from science/space exploration because mythology has no place there.
Captain Stumpy
4 / 5 (21) May 05, 2016
Can anyone remember one having an account deleted for just one deleted post?
@chileastro
yep. for a death threat
although i think the account you're referring to likely got deleted for stating PO was pandering to the trolls... perhaps you contact the site and complain more about the trolls, liars, idiots and request moderation?
I've submitted a plan that would be minimal set-up cost (just adjusting some profiles for temp bans) and free moderation from the existing profiles, with a list of the best candidates known to be degree holing professionals (- not like gkam)

push for it

.

.

EU sewer-rat @cantgetitright gets it wrong
@FSC
funnier still, the lead author and contact VP's the Princeton Plasma Physics Lab

http://www.pppl.gov/news/2016/02/mccomas-named-vice-president-princeton-plasma-physics-laboratory" title="http://http://www.pppl.gov/news/2016/02/mccomas-named-vice-president-princeton-plasma-physics-laboratory" rel="nofollow" target="_blank">http://www.pppl.g...boratory

IOW- that study is chock full of folk who specialise in nothing but plasma physics
LOL
http://www.pppl.gov/
gkam
2.9 / 5 (19) May 05, 2016
"a list of the best candidates known to be degree holing professionals (- not like gkam)"
------------------------------------------
Let's compare university degrees, shall we? What university degree do you "hole"?

How about actual experience?

You first. You saw mine already, most of it. There is still a surprise or two for you to find, but that is most of it.

Give up your need to "get even" with those of us who proved you to be just a nasty guy with sensitive feelings, so we can discuss the science.
Captain Stumpy
2.8 / 5 (20) May 05, 2016
going to reply once
so we can discuss the science
this requires evidence, links and references which you have yet to be able to provide *supporting your arguments*
your arguments tend to be predominantly anecdotal and from authority

when you claim to have a degree, therefore you *must* be correct despite the evidence proving you're wrong or lying then it stops being about science and becomes about a pathological need for attention (AKA- Trolling) and disruption of content with narcissistic promotion of self (sociopathic/psychopathic)

thus you demonstrate Dunning-Kruger, not science
See links below for evidence

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

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

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

just to link a FEW
so my degree's are not relevant because i'm not making the argument from authority

reported for spamming/baiting/trolling per our agreement
gkam
3.2 / 5 (20) May 05, 2016

Without a degree or experience in these fields, your ideas have no merit, according to your own analysis.

- Reported for improperly using the report function.
gkam
3.2 / 5 (20) May 05, 2016
BTW, Rumpy, look up how to use the apostrophe.

Thanks.
obama_socks
2 / 5 (16) May 05, 2016

Without a degree or experience in these fields, your ideas have no merit, according to your own analysis.

- Reported for improperly using the report function.
- gkam
LOL I find it interesting and humorous that Cap'n StumpRump regards you (and others) as a "troll", while at every opportunity the Rump Captain can't seem to help herself in paying an enormous amount of attention to you, no matter in which thread you have made comments.
There must be a psychological description for such an action and motivation on Cap'n Rump's part of her/your relationship.

Dunning-Kruger may also apply to Cap'n Rumpy's obsessive demands for substantiation/evidence as though she is a college professor conducting a test/examination where "trolls" will be given grades A+ to F for Fail.
And yet, Rumpy can ONLY quote from Wiki and other Search sources while offering links to what she has learned so that "trolls" can also learn from the same source(s). You are feeding Rumpy's huge ego, IMO
obama_socks
2 / 5 (16) May 05, 2016
@gkam
It appears that Cap'n Rumpy's high-flying ego soars only when she has found someone to belittle, curse out, and "dress-down" for failing to pass her "tests".
But I also notice that you, gkam, are encouraging Cap'n Rumpy's trolling habits while she pretends only to care about the science. Rumpy, as well as Otto and Ira are trolling YOU, benni, bschott and antigoracle, mainly. They can't abide your presence in these forums. You give them discomfort with all your talk of having degrees and various accomplishments.

There seems to be no solution to this silly nonsense.
bschott
1.7 / 5 (17) May 05, 2016
They can't abide your presence in these forums.


There seems to be no solution to this silly nonsense.


The only way for me personally to avoid the silly nonsense is avoid commenting, and simply expect it when I do. Most of my comments center around the purely mathematical nature (no observational proof other than inferred effects) of theoretical astrophysics. Usually I am told by someone who considers themselves an authority, how the math verifies the assumptions.

You can't debate against anyone who employs that kind of logic (or their devout followers who lap up everything they say)....you can mathematically describe ANYTHING....real or not.

Most of them cannot see how rediculous the picture is that their equations are painting because they can only look at part of the picture at a given time and they hate when a simple example shows a big the holes are.

bschott
1.5 / 5 (16) May 05, 2016
Simple example - What prevents all stars from "collapsing" under the gravity generated by their own mass? Answer, thermal pressure.

Question, how does DM remain in a halo when it is immune to thermal influences and is thus far only inferred to act as a source of gravitational attraction? In other words, what keeps it all apart? The only repulsive force in the standard model is factored in as thermal pressure....

Look at how many crazy theories have made it through peer review based on a proposed DM generated effect just because the math can be made to work out.

Bottom line, unless I actually feel like a mud sling fest it's easier to just sit back and laugh at the lunacy. Now I think I'll mosey on over to the comments under the 2nd law thing and laugh at how they all admit the fourth dimension is a mathematical construct and claim the universe is a closed system because although we haven't seen "the edge" of it, we can hypothesize as an outside observer.
wduckss
1.3 / 5 (12) May 05, 2016
jim_xanara

"Rings on Pluto? Quote from the article in 2013: Until some other opportunity, maybe already in the spring of 2015, when the New Horizons mission will have reached Pluto, to convince us that it does not have rings. The calculations are clear: slow speed of rotation around its own axis, small mass, and even though there is very favorable low temperature, there are no rings. but, it is needed to point out that the values are contiguous, which is demonstrated by the mass of its satellites. Related to their home planet, they are in terms of mass by far beyond the average of the Sun and other planets 8. " Comentar to:http://www.space....comments etc., etc.
Noumenon
2 / 5 (21) May 05, 2016
He's a troll, full stop. I thought we weren't supposed to blithely feed the trolls. I say you tell his ilk- the kind that have zero interest in the topics, just want to spew "science is a fairy story!"- to get off in the rudest possible terms, or say nothing. Gratuitously feeding them like that, imho, is as bad as the post itself.


You're the biggest disruptive troll posting at phys.org,... with your multitude of troll-rating accounts...

..........NiteSkyGerl, antigoresockpuppet, fckthierreyhenry, BongThePuffin, john berry_hobbes, maloderousmiscreant, YoureAPeanut, GoshURStupid, tooty, jim_xanara, AGreatWhopper, chileastro..........

all mass troll-rating my posts irrespective of content going back 6 pages, as in the following thread with factual posts.........

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

This is not a scientific journal. Use the ignore option, or stop interjecting your off-topic disruptions yourself into the thread.
Phys1
4.8 / 5 (16) May 05, 2016
Usually I am told ... how the math verifies the assumptions.

Math never does. It turns assumptions into predictions, which can then be verified or falsified by observation.
What prevents all stars from "collapsing" under the gravity generated by their own mass? Answer, thermal pressure.

Add to that Pauli exclusion.
Besides, stars actually _do_ gravitationally collapse resulting in white dwarfs, neutron stars, quark stars , who knows ...
how does DM remain in a halo when it is immune to thermal influences and is thus far only inferred to act as a source of gravitational attraction? In other words, what keeps it all apart?

Inertia.
Look at how many crazy theories have made it through peer review based on a proposed DM generated effect just because the math can be made to work out.

If the math works out and the predictions are falsifiable but have not yet been falsified, they _should_ pass peer review.
bschott
1.5 / 5 (15) May 05, 2016
OK, let's handle one thing at a time.

Inertia.


Explain. Since it can only be gravity that imparted the inertia on the particles. Or is the theory that they were "created" and entered into the universe already in motion?

Phys1
4.7 / 5 (13) May 05, 2016
The hypothetical DM moves in orbits determined only by gravitation and inertia. Its energy is conserved. So it goes from high gravitational potential and low speed, far from the center, to low gravitational potential and high speed, close to the center, and then back out again to the high gravitational potential ands the low speed. It never loses energy due to radiation. Only if it directly collides with other DM or ordinary matter it may lose energy.Thermalisation due to gravitational exchange of momentum and also gravitational radiation occur but these effects are very small. Much like the Earth keeps going around the Sun, DM keeps its orbit by inertia.
Gravity does not impart inertia on matter.
physman
4.2 / 5 (15) May 05, 2016
+bschott I think the upshot of why Dark Matter doesn't clump together is because in order to be clumped you have to be stationary. In order to make a moving particle stationary it must lose energy. Dark Matter predominately (only?) interacts gravitationally and so there are no dispersive forces at work to slow them down. This is unlike normal (electromagneticly interacting) matter particles where there are dispersive forces like friction slowing the particles down.

Instead these Dark Matter particles would just fly towards eachother due to the mutual attraction and then just fly off into the distance with all their energy in check.

Edit: this is an invigorating read!

https://medium.co...ig1wet4v
Phys1
4.7 / 5 (12) May 05, 2016
One thing at a time is good scientific practice.
bschott
1.5 / 5 (16) May 05, 2016
The hypothetical DM moves in orbits determined only by gravitation and inertia. Its energy is conserved. So it goes from high gravitational potential and low speed, far from the center, to low gravitational potential and high speed, close to the center,


Instead these Dark Matter particles would just fly towards eachother due to the mutual attraction and then just fly off into the distance with all their energy in check.


I was more wondering how they manage to stay away from the large gravitational fields of the massive objects we can actually see. Without a production mechanism to renew itself, after 13.5 billion years of only being pulled towards the largest gravity field in the vicinity, how is there a "halo" surrounding the galaxy. Eventually, because thermal repulsion wouldn't stop it, all the particles would have to end up in clumps in the centers of stars.

bschott
1.5 / 5 (15) May 05, 2016
Gravity does not impart inertia on matter.


How does matter that only reacts gravitationally gain inertia in the first place?

Gotta go lads, looking forward to picking back up tomorrow.
Phys1
4.7 / 5 (12) May 06, 2016

I was more wondering how they manage to stay away from the large gravitational fields of the massive objects we can actually see. Without a production mechanism to renew itself, after 13.5 billion years of only being pulled towards the largest gravity field in the vicinity, how is there a "halo" surrounding the galaxy. Eventually, because thermal repulsion wouldn't stop it, all the particles would have to end up in clumps in the centers of stars.


The DM falls in, gains speed, comes out on the other side with exactly the same kinetic energy. Newton's second law in operation in the presence of gravity. The DM particle does not lose any energy, nothing changes, hence inertia.
How a halo results from this nobody knows, yet.
RealityCheck
1.5 / 5 (16) May 06, 2016
Hi Phys1, bschott, everyone. :)

Phys1, what you just pointed out is what I also pointed out long ago. That is why 'exotic' (ie, non-electromagnetically interactive) DM is NOT logically/physically tenable hypothesis for (observed) galactic Rotation Curves and (alleged) 'exotic DM' 'clumps/toruses'. Add the alleged cosmological 'expansion' claimed, and 'exotic' DM should be totally dispersed in equilibrium by inertial/kinetic SEPARATION into a diffuse 'gas' everywhere with no 'lumps' in it (for the very reasons you just iterated; and which I also have been pointing out for years). Add also recent/increasing discoveries of ORDINARY erstwhile 'dark' matter in many forms, plus my pointing out the NON-Keplerian orbits within spiral galaxies being still MIS-interpreted as 'needing exotic DM', and you can see just how UN-tenable all that 'exotic' DM interpretations/claims/excuses are in reality.

How long do you think it will be before mainstream 'papers/articles' self-correct? :)
Phys1
4.7 / 5 (14) May 07, 2016
@RC
I have to change my statement.
The wikipedia article on DM halo formation suggest that "virialisation" is the mechanism. This must means repartition of energy through gravitational interaction.
https://en.wikipe...er_Halos
RealityCheck
1.5 / 5 (17) May 07, 2016
Hi Phys1. :)

Don't sell yourself short, mate; your initial statement was spot on. If you read your wiki reference closely you will note that no actual 'mechanism' is identified or explained, only 'labeled' as 'virial'' but without logical/physical basis for how and why such initial perturbations should not disperse due to cosmological expansion and lack of e-m interactions which would slow their initial inertial speeds (just as you stated).

So your point/statement remains unchallenged. That wiki merely makes a vague claim of "virialisation" but does not actually explain how that comes about and persists in the face of expansion/dispersion as you earlier observed. Moreover, the Cold DM hypothesis has recently been challenged by the Hot DM hypothesis after simulations (by one of the 'fathers' of the Cold DM hypothesis) which show similar cosmological distribution 'results'. But in any case, no 'exotic' DM is tenable (for reasons you and I together have pointed out above). :)
Phys1
4.7 / 5 (14) May 07, 2016
Hi Phys1. :)

Don't sell yourself short, mate; your initial statement was spot on. ... a vague claim of "virialisation" but does not actually explain how that comes about

To me as a physicist it is clear what this means. It means that gravitational interactions between hypothetical DM particles are enough to cause halo formation. You are correct that the present formulation is vague to the less specialised reader. This should have been made much more explicit. Halo formation probably also means that DM is absorbed by the central black hole, although this should be an extremely small amount due to the tiny dimension of the BH.
sizzlerjoe11
1.4 / 5 (11) May 07, 2016
Gravity does not impart inertia on matter.


How does matter that only reacts gravitationally gain inertia in the first place?

Gotta go lads, looking forward to picking back up tomorrow.

Matter reacting to gravity, being pulled towards it, gains speed, more inertia.So gravity does add inertia to matter. Matter has it's own attraction to gravity as well. There just needs to be enough gravity in the first place.

Phys1
4.7 / 5 (12) May 08, 2016
@sizzlerjoe1
The expression "more inertia" has no physical meaning as inertia is not a quantity.
https://en.wikipe.../Inertia
bschott
1.6 / 5 (14) May 09, 2016
How a halo results from this nobody knows, yet.


Not to mention that all that "gravity" moving "through" sources of gravity doesn't displace ANYTHING, and instead somehow acts as a pretty tight "holding mechanism" on a galactic scale.

I guess we can chat again when all the bugs are worked out.
Phys1
4.6 / 5 (10) May 09, 2016
@bs
I retracted that statement in favour of virialisation. So don't quote me without also quoting the retraction.
bschott
1.6 / 5 (14) May 09, 2016
@bs
I retracted that statement in favour of virialisation. So don't quote me without also quoting the retraction.


Virialisation is not a mechanism, it is the mathematical solution for Halo maintenance, and is a great way to try to smooth the math for the overall halo structure, but as DM is theorized to gravitationally interact with massive bodies as you say ( elastically boucing back and forth through them), the lack of any type of displacement observed in those bodies suggest no DM interaction.

There have been several papers written about the "roundness" of the sun. That roundness would be impossible if DM was continuously interacting with it as it is theorized....

Perhaps DM collisions in the core provide the energy for fusion which is why we can't get it to work here....just kidding.
Phys1
4.6 / 5 (10) May 09, 2016

Virialisation is not a mechanism,

Correct, it is the consequence of a physical coupling of the DM particle motion, in case by gravity. The strength of the coupling determines the time scale over which the virialisation takes place.
it is the mathematical solution for Halo maintenance, and is a great way to try to smooth the math for the overall halo structure,

It is not mathematics it is thermodynamics.
but as DM is theorized to gravitationally interact with massive bodies as you say ( elastically boucing back and forth through them), the lack of any type of displacement observed in those bodies suggest no DM interaction.

You can not draw such conclusions without a detailed prediction of how large such "displacements" should be and without an observation showing disagreement with this prediction.
Phys1
4.6 / 5 (10) May 09, 2016
There have been several papers written about the "roundness" of the sun.

You probably mean flattening at the poles?
That roundness would be impossible if DM was continuously interacting with it as it is theorized....

This statement is very far from the truth. There is no way that DM would cause deformation of the sun, but surprise me.
AlbertPierrepointOBE
3.4 / 5 (17) May 10, 2016

cantdrive85 1.4 /5 (18) May 04, 2016
Surprise, surprise, surprise...


that the most brainless comment
On this thread
Is from CD85!
bschott
1.6 / 5 (13) May 10, 2016
It is not mathematics it is thermodynamics.


Thermodynamics.... "matter" immune to EM interaction is affected by thermodynamics...OK.

You probably mean flattening at the poles?


We are talking about the sun...not earth.

http://news.natio...ce-nasa/

You can not draw such conclusions without a detailed prediction of how large such "displacements" should be


We are talking about DM, ANY conclusion about it is speculation at best.

and without an observation showing disagreement with this prediction.


See above link.

There is no way that DM would cause deformation of the sun, but surprise me.


Are you drawing a conclusion? Need me to link to a theory where gravity causes deformation of an object? You told me how DM interacts with massive objects, do we see fluctuations in the mass of all bodies due to DM constantly entering and exiting them?

Lots of holes to fill in.

Phys1
4.6 / 5 (9) May 10, 2016
We are talking about the sun...not earth.

Why, I am talking about the sun.
"the Sun is a near-perfect sphere with an oblateness estimated at about 9 millionths"
Oblateness means flattening.
https://en.wikipe...attening
You can not draw such conclusions without a detailed prediction of how large such "displacements" should be

We are talking about DM, ANY conclusion about it is speculation at best.

Conclusions are not speculations and vice versa.
and without an observation showing disagreement with this prediction.

See above link.

Be more specific.
There is no way that DM would cause deformation of the sun, but surprise me.

Are you drawing a conclusion?

Yes. Even the planets do not deform the Sun, let alone a uniform very sparse DM distribution.
"The tidal effect of the planets ... does not significantly affect the shape of the Sun."
https://en.wikipe...wiki/Sun
Phys1
4.6 / 5 (9) May 10, 2016

Need me to link to a theory where gravity causes deformation of an object?

No need. I know that the gravity of the Andromeda system deforms your nose.
You told me how DM interacts with massive objects, do we see fluctuations in the mass of all bodies due to DM constantly entering and exiting them?

Make falsifiable predictions if you want to make a case.

Lots of holes to fill in.

You yet have to expose any.
Surprise me.
Phys1
4.6 / 5 (9) May 10, 2016
No offense intended. Andromeda deforms everybody's nose.
bschott
1.6 / 5 (14) May 11, 2016
You yet have to expose any.


You use a thermodynamic equation to mathematically describe the structure supposedly created by a theoretical (as of yet unobserved) particle who's only definite property is that it does not interact electromagnetically.

There is no observation of it interacting with anything except via inferred effects, only supported through math. It only reacts gravitationally, has inertia, yet you claim the inertial motion was not imparted by gravity.

You apparently don't think gravity can deform anything except for my nose and you contradicted yourself or several times above regarding the hypothetical properties of DM, yet you claim to be a physicist.

bschott
1.5 / 5 (15) May 11, 2016
The hypothetical DM moves in orbits determined only by gravitation and inertia.


So it only interacts with gravity and via gravity and it moves but gravity didn't do it....hmmm

Its energy is conserved. It never loses energy due to radiation. Only if it directly collides with other DM or ordinary matter it may lose energy


Without EM interaction, how is supposed to collide with ordinary matter?

Thermalisation due to gravitational exchange of momentum


No EM interaction yet thermalisation occurs...

and also gravitational radiation


What is the unit of measure of a quanta of "gravitational radiation"?

Make falsifiable predictions if you want to make a case.


I predict that before either of us dies, the current version of the standard model will, along with all of its "phantom" components which currently only manifest as math holding it together as a theory.

If you don't acknowledge the holes, you fall into one, see above.

Captain Stumpy
4.2 / 5 (15) May 11, 2016
... flattening at the poles?
... talking about the sun...not earth
http://news.natio...hic.com/
@bs
see first paragraph below, and then read under the header "Our flatter sun"
http://www.space....led.html

theoretical (as of yet unobserved) particle
*the particle* is unobserved
it's *effects* are observed which is where the whole DM theory comes from (and why we're testing various methods for specific identification of said particle with falsifiable predictions)
I predict that before either of us dies, the current version of the standard model will, along with all of its "phantom" components which currently only manifest as math holding it together as a theory
did you leave some important stuff out of that post?
you predict it will what?

and if your talking eu, remember eu is already falsified
this is like the FDA/mag-cancer conversation we had - how can you support something that has no evidence but anecdote?
cantdrive85
1.9 / 5 (13) May 11, 2016
Why, I am talking about the sun.
"the Sun is a near-perfect sphere with an oblateness estimated at about 9 millionths"
Oblateness means flattening.
https://en.wikipe...attening

Well, both you and wiki are out of date and as usual, wrong.

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

Odd that a physicist would rely so heavily on wiki, more of an arm chair "physicist" I suppose.
bschott
1.6 / 5 (14) May 11, 2016
did you leave some important stuff out of that post?
you predict it will what?

Read carefully:
I predict that before either of us dies, the current version of the standard model will,

quoted as typed for the lazy reader.
Well, both you and wiki are out of date and as usual,

As usual.
this is like the FDA/mag-cancer conversation we had -

Not even close.
how can you support something that has no evidence but anecdote?

Observe it work repeatedly.

Also a funny question to ask in a discussion about an imaginary substance who's existence you support. But hey, irony is usually lost on the mentally inept.

remember eu is already falsified


So is the standard model unless you buy into the mathematical kludges used to attempt to keep it valid. Above you have a self proclaimed physicist who can't even see the contradictory nature of the answers he HAS to provide to simple questions regarding motion.

bschott
1.5 / 5 (15) May 11, 2016
Now Captain, why don't you try to help out Phys1 and address the myriad of physics/math problems with his answers (that would be everything in my posts you avoided talking about....for some reason) instead of showing up to offer your opinion, bring up topics completely unrelated to the discussion, and attempt to prove a point by linking a peer reviewed paper that contradicts another peer reviewed paper. (this is irony as well being as you CLAIM to trust EVIDENCE, which means you have to trust both papers).

cantdrive85
1.7 / 5 (12) May 11, 2016
remember eu is already falsified

Ummmm, not even close. Please link the peer-reviewed paper which specifically falsifies the EU theory. No pseudoscience blogs from "Pith ball" Timmy Thompson or some other acolyte of the dark sciences. Only peer-reviewed papers which specifically addresses claims made by EU. With all your constant claims this should be easy enough even for you.

Phys1
4.6 / 5 (9) May 11, 2016
The hypothetical DM moves in orbits determined only by gravitation and inertia.


So it only interacts with gravity and via gravity and it moves but gravity didn't do it....hmmm

Its energy is conserved. It never loses energy due to radiation. Only if it directly collides with other DM or ordinary matter it may lose energy


Without EM interaction, how is supposed to collide with ordinary matter?

Thermalisation due to gravitational exchange of momentum


No EM interaction yet thermalisation occurs...

and also gravitational radiation


What is the unit of measure of a quanta of "gravitational radiation"?

There are too many misinterpretations and holes in your ideas to repair in a post. You should study physics or give up.
Phys1
4.6 / 5 (9) May 11, 2016
Why, I am talking about the sun.
"the Sun is a near-perfect sphere with an oblateness estimated at about 9 millionths"
Oblateness means flattening.
https://en.wikipe...attening

Odd that a physicist would rely so heavily on wiki, more of an arm chair "physicist" I suppose.

Nothing is out of date neither in PO article nor in the wiki article. They agree on essential points. Had you read on to get to the scientific reference at the end, you would have seen that the wiki page is a good introduction to the picture emerging from the latest greatest research. Unfortunately, narcissism prevents you from acknowledging science of which you are incapable and profoundly jealous. Check with a psychiatrist if you do not believe me.
bschott
1.6 / 5 (14) May 12, 2016
There are too many misinterpretations and holes in your ideas to repair in a post. You should study physics or give up.


There are too many contradictions in your posts which you ALWAYS fail to address and then need to attempt to end a discussion by saying something like the above. Fortunately anyone taking the time to read your comments, then my responses can see this. If your physics education produces the above responses when challenged, you should study something less difficult for your brain to reconcile.

You apparently cannot even understand why "NO EM interaction"...then using thermodynamic smoothing equations or terms such as thermalisation cannot physically apply to something that doesn't interact electromagnetically...plus you actually said it collides with ordinary matter after saying it passes through stars.

You either need to pay more attention in class or pursue a different career. Or what they are teaching you is....suspect.

Good luck.

Phys1
4.5 / 5 (8) May 12, 2016
@bschott
you are just echoing my statement.
thermodynamics always applies. all it requires is an interaction.
gravity fits the bill. em interaction is not needed.
you raise so many controversial points that it would take too much of my time and energy to react appropriately.
one point at a time is good scientific practice.
Phys1
4.5 / 5 (8) May 12, 2016
Now Captain, why don't you try to help out Phys1

It is _you_ who needs help. You don't have enough knowledge to address the issues that you address but you fail to see this.
So good luck with it.
Phys1
4.5 / 5 (8) May 12, 2016
@bschott
Echoing is troll behaviour.
bschott
1.6 / 5 (13) May 12, 2016
you raise so many controversial points that it would take too much of my time and energy to react appropriately.


When you make a controversial statement I point it out, it is not me raising these points, it is the logical response when questioning what you say.

thermodynamics always applies. all it requires is an interaction.


It's stuff like this, you cannot apply thermodynamics to theoretical particles if the basis of your theory has the defining property of the particle as completely EM transparent. A particle which only interacts via gravity cannot experience any repulsive force from anything, any temperature keeps things apart.

Particles which only interact via gravity and are in motion MUST have acquired that motion due to gravity, you flat out said they don't.

It is _you_ who needs help.


Clearly not. I obviously have enough knowledge to force you into dodging the issues with what you say. Then trying a cop out troll remark.

bschott
1.6 / 5 (13) May 12, 2016
@phys1

Your favorite source:
https://en.wikipe...dynamics

The first line of the definition immediately exempts these laws from applying to DM, based on the main property (complete EM transparency) the particle MUST have if it exists. If you are telling me the equations you are being taught to model DM interactions are based on thermodynamics, and you don't see a problem or a contradiction here, you, and the rest of mainstream theoretical science is beyond help.

If you are math adept and only claiming to be a physicist or a physics student, then these enormous gaffs, coupled with some math related comments i have seen you post make a lot more sense.

Meaning you have just showed up here to try to troll people who don't believe as you do. If that is not the case then address the issues with your comments, or enjoy being a math adept captain stumpy....at least you'd have one quality saving you from just being useless.

Phys1
4.5 / 5 (8) May 13, 2016
"describe a body of matter or radiation"
I would like to stress "or".
There is no contradiction.
Gravitational interaction can produce equipartition of energy.
Phys1
4.5 / 5 (8) May 13, 2016
you raise so many controversial points that it would take too much of my time and energy to react appropriately.


When you make a controversial statement I point it out, it is not me raising these points, it is the logical response when questioning what you say.

As I said there are so many controversial statements in that post that any discussion will diverge even further and no conclusion of even clear positions will result. One issue at a time or else I "cop" out.
bschott
1.6 / 5 (13) May 13, 2016
"describe a body of matter or radiation"


Anything with a measurable energy level in the EM spectrum.

I would like to stress "or".
There is no contradiction.


Until you put the word "dark" in front of matter and define it as mainstream physics does.

Gravitational interaction can produce equipartition of energy.


DM has no energy content. That's it's defining property. Are you saying that in order to model it you have to use equations which apply an energy to it? Are you saying Gravity imparts energy to the particle? There is no mass/energy equivalence for DM because it has no energy, and technically no mass. A DM particle is literally a moving "hole" in space that somehow has the property of gravity.

You can't describe DM in any way other than the math you use to model it, and you use formulas based on matter interaction to do this so you keep inserting terms which cannot possibly apply to DM.

I can see why you're confused.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.