Voyager 2 Detects Peculiar Solar System Edge 272
ClickOnThis writes "CNN reports that Voyager 2 has detected evidence of the magnetic edge of the solar system (aka the heliopause) at 76 AU (1 AU = 93 million miles), much closer to the Sun than the location of 85 AU found by Voyager 1. From the article: 'This implies that the heliosphere, a spherical bubble of charged low-energy particles created by our Sun's solar wind, is irregularly shaped, bulging in the northern hemisphere and pressed inward in the south. [...] The researchers think that the heliosphere's asymmetry might be due to a weak interstellar magnetic field pressing inward on the southern hemisphere.'"
I knew it (Score:5, Funny)
Re:Wait for it... (Score:3, Funny)
WTF? (Score:3, Informative)
Global warming, we have a well understood and physically justified model whose conclusions are gradually confirmed by more and more evidence.
Heliopause, we have a naive model based on little evidence, whose conclusion - uniformity of the Heliopause based on lack of apparent altering factors - is refuted by two pieces of probably not very significant evidence. We have no h
Re:WTF? (Score:3)
No.
There are serious scientists who question the theory that global warming or climate change as it's more properly called now is caused by human activity.
Just check out wikipedia [wikipedia.org]
But hey, if I were an intellectually lazy armchair scientist, I'd probab
Re:WTF? (Score:3, Informative)
The links you sent regarding the political advertising campaign Competitive Enterprise Institute is not germain to the discussion of whether there are real scientists who have concerns regarding global warming. That's politics.
The article you point to states:
The 928 papers were divided into six categories: explicit endorsement of the consensus position, evaluation of impacts, mitigation proposals, methods, paleoclimate analysis, and rejection of the consensus position. Of
Re:Wait for it... (Score:4, Funny)
Variable size? (Score:5, Insightful)
Re:Variable size? (Score:3, Insightful)
What I'm trying to say here: If it's moving, it's doing so with some gusto, at least in planetary terms.
Re:Variable size? (Score:4, Insightful)
Re:Variable size? (Score:2)
We'll have a better picture when the Voyager 1308 readings get to us. Stay tuned !
Re:Variable size? (Score:5, Informative)
Oh, No! (Score:4, Funny)
It must have started after Voyager I got there, which means it's going *really* fast.
Run everyone, Ruuuuuuuuuuuuuuuuuuun!
Re:Oh, No! (Score:4, Funny)
"Computer, what is the nature of the universe?"
"The universe is a spheroid region, 705 meters in diameter."
spheroid region? (Score:5, Funny)
Re:Variable size? (Score:2)
Re:Variable size? (Score:2)
Re:Variable size? (Score:5, Insightful)
Re:Variable size? (Score:3, Informative)
Re:Variable size? (Score:3, Insightful)
Re:Variable size? (Score:2)
Of course, I'm pulling that straight out my ass.
Re:Variable size? (Score:2, Funny)
The source?
If it's daytime: go outside and look up.
If it's night time: wait until daytime and see above.
Re:Variable size? (Score:2)
Comment removed (Score:5, Insightful)
Re:Variable size? (Score:2, Funny)
Re:Variable size? (Score:3, Funny)
For further background on this concept, you may be interested to read about galaxies [seds.org] or Copernicus [wikipedia.org].
Re:Variable size? (Score:3, Informative)
Think: Earth's magnetic field.
The magnetic field of the earth is shaped very much like a comet, but it is always pointed away from the sun and ripples as solar output changes. There is a website that seeks to model the fluxuations of the magnetic field, but I forg
Re:Variable size? (Score:4, Funny)
-Elaine
Re:Variable size? (Score:2)
Re:Variable size? (Score:3, Insightful)
Excellent point. Whether something changes spatially or temporally is a difficult thing to determine when you're measuring things from just a few spacecraft. My guess is the feature is spatial, because the two Voyagers encountered it within such a relatively short time period. However, if it is temporal (i.e.
Re:Variable size? (Score:5, Interesting)
What variability? The sun is pretty constant on short time scales. The sun is being observed in detail by other spacecraft specifically designed for that task, like Helios. These spacecraft directly measure the solar wind and track the effects of solar. I'm sure the people at NASA have included that data into their analysis. They are rocket scientists, after all. The planets exert essentially zero influence over the heliosphere. So it's not like they have no idea about what's going without the Voyager data.
Re:Variable size? (Score:4, Insightful)
"...based on all the variable energy in the solar system."
What about the energy outside the solar system? Although the distance is much greater between the sun and neighboring stars, those stars do have a gravitational effect on the movement of the sun, the planets, and all other objects in the solar system. They probably have an electro-magnetic effect as well.
Re:Variable size? (Score:3, Insightful)
And the width of planets are insignificant compared to the radius of orbit, so unless the spacecraft happened to hit a one in a million chance of wandering through right on the orbital plane of one of the planets, just in sync with the orbit of that planet, this isn't a very likely explanation either.
Re:Variable size? (Score:3, Informative)
That's actually very likely taken into account. When Voyager 1 found the heliopause, they were pretty sure that the termination shock was moving inward fairly rapidly due to it being past solar max, and so Voyager 2 would catch it pretty soon. This sounds like it happened quicker than their predictions expected.
Re:Variable size? (Score:2)
Er. Wait. (Score:5, Insightful)
Wouldn't it be equally as logical to say that it's just expanding/contracting? How can they know with only two points?
Re:Er. Wait. (Score:2)
Re:Er. Wait. (Score:2)
Re:Er. Wait. (Score:5, Interesting)
The theoretical belief is that it should be relatively uniform, but it does not appear to be. Are 2 observations sufficient? No, but a difference in 9 AU in the 2 observations is significant in that it is far off the scall were it less than 1, or maybe only slightly different, that would better confirm the theory. If the physics say that it ought to be uniform, and observations shows that it isn't, th theory needs to be adjusted.
Re:Er. Wait. (Score:2)
Seriously, when you make a theory with no actual data, it sounds a lot like an educated guess. I'm not saying it shouldn't be done, but you'd be a fool to be surprised it was wrong or incomplete. It's a starting point, not a destination.
Re:Er. Wait. (Score:2)
Re:Er. Wait. (Score:3, Informative)
Actually there is more information available than just two data points. There is the a priori knowledge of how magnetic fields and plasmas behave, the cumulative measurements of the two Voyager probes up to now along their trajectories, the
Re:Er. Wait. (Score:4, Informative)
Someone once explained the heliopause neatly by pointing to the splash-disk of water in a sink, with the tap turned on full. The water coming from the tap pushes out, while the water already in the sink is trying to return to the middle to go down the drain.
Hence, you get a 'circle' where the energy of the tap water (coming out from the center) = the energy of the material trying to fall back into the center. The circle isn't perfect; it moves as the tap outpouring is not uniform and varies quite a bit.
It's actually a pretty good analogy, since the topagraphy of the sink (as a parallel to the gravity environment) also affects that 'circle' significantly.
Much like that, I suspect that the heliopause is hardly static; it probably bulges and deflates dynamically with solar activity (once that reaches the periphery, of course).
We need more samples! (Score:2)
Correct me if i'm wrong... (Score:5, Funny)
Couldn't the inward bulge on the south be because the turtle shell is pushing in on it?
Re:Correct me if i'm wrong... (Score:3, Funny)
Yes, as any serious thinker knows: "it's turtles all the way down".
Exactly what I was thinking! (Score:2)
Duh!
garbage! (Score:2, Insightful)
Let's sample a sphere at two pinpoint locations, and make all sorts of conclusions on the shape of an entire hemisphere of it...??? It rained today, and it was sunny yesterday, so that means that there's a 50% chance of it raining? Insufficient data...
Re:garbage! (Score:5, Informative)
Re:garbage! (Score:5, Insightful)
MOD PARENT UP! (Score:2)
Actually, you're in good company [wikiquote.org].
Re:garbage! (Score:2)
Yes, you---a slashdot armchair physicist---have disassembled and shamed the work of a team of NASA scientists with three poorly punctuated semi-sentences.
Let that be a lesson to the rest of you would-be geniuses out there using your "science" and "math" to "prove facts". Quasar1999 stands at the ready to quip your supposedly careful research into shamed oblivion.
Tom Caudron
http://tom.digitalelite.com/ [digitalelite.com]
Re:garbage! (Score:3, Informative)
You expect the termination shock to be symmetric, with the Sun at the centre. There will be interstellar influences, but the Voyagers are
Re:garbage! (Score:2)
You lie! Everyone knows the heliopause exists only because the Designer placed it there! To suggest otherwise blasphemes the Designer!!! (/sarcasm)
Or perhaps... (Score:2)
Re:Or perhaps... (Score:3, Interesting)
Unless the compression of the heliopause is on the leading edge relative to the sun's motion through the galaxy, this can be safely ruled out. This would also imply some hitherto undetected galactic medium causing a braking effect; surely any non-magnetic influence would affect solid matter as well, and cause the galaxy's rotation to slow over time (unless the medium rotates with the galaxy, in which case the motion of the medium relative to the sun is zero
Other possibilities (Score:4, Funny)
Re:Other possibilities (Score:3, Funny)
Re:Other possibilities (Score:2, Funny)
I think if we draw off about 10% of our reserve holodeck power and re-route it to the rear sensor array, the resulting harmonics would induce a tachyon burst in all direc
Re:Other possibilities (Score:2)
Re:Other possibilities (Score:2)
Also, Occams razor PROVES it, because its much easier to imagine some guy coming along and just plonking the heliosphere there rather than an uncountable number of magnetic particles/waves interacting with one another over billions of years.
Re:Other possibilities (Score:3, Funny)
Re:Other possibilities (Score:2)
Re:Other possibilities (Score:2)
two points of contact describes the shape? (Score:2)
Re:two points of contact describes the shape? (Score:2)
I hope someone programmed that thing with.... (Score:2, Insightful)
Obligatory Global Warming Link? (Score:3, Funny)
A) Say that this is causing global warming
B) Say that this is being caused by global warming
Re:Obligatory Global Warming Link? (Score:2)
here's a question you shouldn't be able to answer (Score:4, Funny)
The universe is a spheroid region - 705 meters in diameter...
Re:here's a question you shouldn't be able to answ (Score:2)
Good Engineering (Score:4, Insightful)
Re:Good Engineering (Score:5, Insightful)
Re:Good Engineering (Score:2)
Good design always has a bit of "luck" involved. There are always assumptions and simplifications nobody thinks are significant, until they are.
Re:Good Engineering (Score:2)
And (until someone else hopefully takes up the spacefaring mantle) all of the human race.
Symmetrical? (Score:4, Insightful)
If you look at many structures in the universe, there are quite a few that are not spherically symmetrical. So either, we're in an asymmetrical blob, or there's just a more complex symmetry present. This should come as no surprise to the astronomy community, IMHO.
It is interesting, I think. It may give insight into our local neighbourhood.
Mike.
Theory (Score:2)
I don't even know why I have to say this. It's scientific method 101.
Humph (Score:2)
What V'ger Wears (Score:3, Funny)
Re:What V'ger Wears (Score:2)
En1arge your heli0sphere (Score:5, Funny)
Or maybe ... (Score:2)
Or maybe it is a regularly shaped sphere but our sun is not the center? Maybe the center is some other extremely dense object, like 's head?
Re:Or maybe ... (Score:2)
Or maybe it is a regularly shaped sphere but our sun is not the center? Maybe the center is some other extremely dense object, like {insert your favorite whipping person here} 's head?
Re:Or maybe ... (Score:2)
Damn magnetic fields.. (Score:2)
Forget Global Warming... (Score:2)
Maybe the turtle's back is squashing it... (Score:2)
A better article... (Score:4, Informative)
Here [newscientistspace.com] is an illustration of the phenomenon.
-mcgrew
Time to rename the helipsphere (Score:2)
I guess we need to change the name of the heliosphere to helioelipsoid or maybe helioblob.
Aldebaran Galactic Warming Treaty of Stardate 2476 (Score:2)
Some corrections and clarifications... (Score:5, Informative)
I forgot whose talk I heard yesterday (they changed the speaking order; session was SH22A) but basically: V1 passed the termination shock (NOT the heliopause; summary is wrong) at the end of 2004; this was the big announcement at last spring AGU meeting. Before that, they were seeing foreshock signatures (plasma and magnetic). V2 is now seeing those signatures, but seeing them a fair bit closer in than V1 was observing them. So, V2 has not passed the heliopause, nor even the termination shock, but appears to be nearing the TS closer to the Sun than V1 did. This is a surprising/interesting result, but not huge overturning of theory or anything. Learning the structure of the outer regions of the Solar System is the whole point of these exercises (and the upcoming IBEX mission).
Well, duh. (Score:2)
I didn't think so. [venganza.org]
Re:oh great (Score:2)
Re:oh great (Score:2)
The sun's magnetic field reverses itself about every 11 years. [wikipedia.org] It would not be good having a refernce based on something that goes changing itself every 11 years or so.
The reference for "north" and "south" w/regard to the solar system is the ecliptic [wikipedia.org].
Re:oh great (Score:2)
Re:oh great (Score:5, Informative)
North and south also refer to magnetic poles. North is generally assumed to be the positive pole, and south the negative, though when poles flip, as happens on earth (every one million years I think), and the sun (every 11 years or so, sometimes refered to as a period of solar maxima), common usage north and south probably won't switch. Wikipedia has a bit more info [wikipedia.org].
There's also galactic north and south, which are imaginary axes perpendicular to the the plane of the galaxy. Again, wikipedia has more info [wikipedia.org].
I'd hazard that what this article refers to as north is probably some assumed "solar north" roughly parallel to Earth's north.
Re:I wonder. (Score:5, Funny)
Re:heliosphere shrinkage - we're the cause (Score:2)
Re:There's a hole in the magnetic layer (Score:2)
Re:after all.. (Score:2)
Socio-politically perhaps. But geometrically, it's an oblate spheroid.
Re:Variable Heliosphere (Score:2)