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An Up-Close Look At the Parker Solar Probe -- the Spacecraft That Will Skim the Sun's Surface (arstechnica.com)
schwit1 shares a report from Ars Technica, offering an up-close look at the Parker Solar Probe: This summer, NASA will launch the Parker Solar Probe, an impressively heat-resistant spacecraft destined to glide closer to the surface of the Sun than any spacecraft before it. It will fly within about 6 million kilometers of the searing surface, more than seven times closer than earlier craft. If all goes to plan, the craft will be hurtling at 724,205 km per hour and have its one-of-a-kind heat shield perfectly facing the surface as it makes those closest approaches. In about seven years, it will complete 24 orbits around the Sun and pass by Venus seven times. All the while, the Parker probe will collect a constellation of data to help answer scientists' burning questions -- and solve some sizzling mysteries -- about the orb of hot plasma that lights up our Solar System. Namely, it will try to help us finally understand why the Sun's atmosphere is 300 times hotter than its surface, which itself is a balmy 5,727C. This fact defies basic physics and to this day is unexplained. One of the leading hypotheses to account for the heat shift comes from famed physicist Eugene Parker, after whom the probe is named. In the mid-1950s, Parker theorized that the Sun's super-heated corona could be explained by a complex system of plasma, magnetic fields, and energetic particles that spark solar explosions called "nanoflares." Scientists are thirsty for close-up data on those potential explosions as well as the cascade of energy called solar wind. With that data, they can put their hypotheses to the test. And in addition to helping us understand coronal heat, data on these sunny phenomena could help clear up poorly understood space weather, which can wreak havoc on satellites and power lines here on Earth.
The plasma increases in density and temperature gradient until some arbitrarily defined point of human definition. If this thing is warping through there 7e5 km / hr then it's obviously nowhere near any surface.
I hope they plan on only going there at night!
#DeleteFacebook
All the while, the Parker probe will collect a constellation of data to help answer scientists' burning questions....
Pun intended I hope
Nah, it's much simpler than that. The core doesn't burn so hot because there's less oxygen in the center than on the exposed surface.
No sig today...
Unfortunately Parker didn't appear in the Sun Probe episode.
....our Sun is not the brightest.
Neither are any of the mentally challenged that kneel before the genitalia of the cult of EU.
Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
Bullshit. Stupid fucking bullshit. Your EU is nothing more than crap, which requires things we've observed, and experimental results from the past 99 years to be completely wrong. Either Relativity is right, or EU is right.. can't be both... and EVERY experiment done has shown Relativity is correct, and on the EU side, they've all shown EU doesn't explain anything experimentally.
Seriously.. what the fuck is wrong with you EU cultists?
Fascism: An authoritarian and nationalistic right-wing system of government and social organization. See also: NAZI's
... except that for some people who have refused to question the worldview which was taught to them in school, for whom disrupting modern science theories is interpreted as an attack upon their own personal worldview. These people can be identified by their emotional rants and general failure to cite technical arguments, and they seem unaware of the fact that their "defense of science" is also a defense against innovation in the sciences.
What kind of materials are used that can take that kind of heat, even a fraction of the heat destroys most electrical component.
Carbon. Sublimates around 3825C or so.
Most of the spacecraft hides behind the carbon shadow shield-- almost all the instruments don't need to look toward the sun (the main interest is plasma and fields). The exception is the solar array (my part of the project!)-- this doesn't work unless it is in the sunlight :). But the sunlight is intense enough that we only need a tiny bit of the array to be illuminated, so we retract most of it into the shadow, tilt the part that does see the sun, and use concentrator solar cells that are actively cooled to keep temperatures reasonable.
Honestly, it is people like you that keep me coming back to /. , I have yet to find a single site to replace it.(sure there is hacknews and reddit...)
Thanks.
http://www.geoffreylandis.com
Adding to IMarv's comments, the sun's neutrino output has at times varied inversely with the sun's surface sunspot count. Were the neutrinos produced in the sun's nuclear core, this relationship would be inconceivable, since solar physicists calculate that it takes about 200,000 years for the energy of internal fusion to affect the sun's surface. The observations seem to raise the possibility that fusion is occurring near the sun's surface, and it only took one non-correlated half-cycle for theorists to completely stop paying attention.
The graph which shows this anti-correlation has been deeply buried in academic papers, so I've published a copy of it here.
One thing to consider, when contemplating the situation of an anti-correlation which apparently switches between on and off states is that the Sun clearly exhibits these different states through its cycle. To observe switching behavior, and immediately use that as reason to discount the existence of an anti-correlation is honestly a rush to judgment. You know, this is why we build models.
EU === Electric Universe, but also EU == electrical cosmology. Its central thesis is that cosmic plasmas behave as laboratory plasmas -- an important claim in light of the realization, since 1958, that most of the matter that we can see with telescopes is matter in the plasma state (>99%).
One thing to know is that in the EU, there is no dark matter problem: Since we clearly observe plasma to conduct in the laboratory, what is being claimed is that the cosmic plasma is conducting across vast distances of space over plasma filaments -- much like what is already observed with a novelty plasma globe. These filaments are referred to by mainstream astrophysicists as "interstellar clouds", but in fact, "clouds" like the Large and Small Magellanic Clouds are highly filamentary. They are hardly the only ones; in fact, hydrogen filaments are ubiquitous in space, and have been shown to precede the formation of stars.
What seems to confuse a lot of people about the debate is that mainstream astrophysicists are arguing against the idea that we can model cosmic plasmas as laboratory plasmas. But, this is indeed the case. They have been using fluids models to model cosmic plasmas, and this creates the extraordinary situation that when astronomical observations exhibit the features of laboratory plasmas, even professional astrophysicists and cosmologists will commonly fail to recognize very common forms observed in the laboratory for electricity over gas. When these failures are pointed out, the debate can become extremely emotional -- and we have a situation where stating "the obvious" creates a very acrimonious situation.
Re: "There is a lot of talk about scientists and very little talk about physical theory. As far as I can tell, EU is some conspiracy theory about scientists as opposed to a science theory. Maybe it would be more attractive and approachable if they drop the antisocial, whiny cruft and stuck to business."
It's probably unfair to judge an entire cosmology through Internet comments. Since a lot of the efforts here are focused upon correcting misconceptions, these efforts may come off to some as "whiny". For a more thoughtful introduction, you might consider, instead, reading The Electric Sky by Don Scott, which goes into great length about how we can explain astronomical observations with ordinary laboratory plasma physics observations.
If you'd prefer to avoid purchasing their book, then consider their technical introduction, The Essential Guide -- which is actually geared towards those with an EE background. It is quite technical.
Alternatively, if you come from the world of plasma physics, you'd want to also supplement these works with the second edition of Physics of the Plasma Universe And in that case, there are also a couple of papers you should read here and here, which both review critiques of MHD in good detail.
Personally, I also recommend focusing upon the historical arguments, whose importance are greatly under-appreciated ... e.g., the mistaken assumption of empty space, the story of Kristian Birkeland, the history of the Birkeland current concept, the electron theory as a worldview, the story of Halton Arp, the Big Bang's big redshift assumption, and this discussion of the debate over uniformitarianism vs catastrophism, for starters.
For those that just want a very basic and quick introduction, then watch these two Youtube videos.
There is really no shortage of high-quality resources, pitched at all of the various levels. If you aren't seeing them, then that definitely says more about your own efforts to find these resources than anything else.
Re: "Uh, the vast majority of models I've seen are at least resistive, and often gyrokinetic or flat out kinetic instead of fluid. PIC is really popular for astrophysical plasmas, and a lot of the work on relativistic plasmas can't be fluid model at all."
There's an overt disconnect between what you are saying and the relentless onslaught of fluids concepts that appears within the analysis of astronomical plasmas. Whether or not the models in use are technically referred to as "fluids models", what is happening with them is that the plasmas are being modeled as fluids, without reference to electrodynamic plasma concepts observed within the laboratory.
There are by now numerous laboratory plasma physics concepts which generally don't appear in astrophysics papers -- including double layers, plasma instabilities (aka Peratt intabilities), z-pinches, critical ionization velocities, Marklund convection, and of course the force-free field-aligned Birkeland current.
Let's take an example from just this week. If you go to the original paper, it states:
But, anybody who has spent time working with electrodynamic plasmas in the plasma laboratory should already be very familiar with the ring of vortices morphology, because this exact type of filamentation is what happens for the highest charge-density state of a conducting plasma, known as the z-pinch. In fact, plasma physicists have been imprinting electron beams onto a variety of materials for many decades now, producing this same form in the laboratory.
When people point out the obvious problem of failing to mention the correspondence between the astronomical and laboratory forms, people who honestly should know better tend to totally lose it, and it honestly creates a very anti-science situation where the exactly correct conversations are apparently out-of-bounds.
Personally, I believe that you understand where the disconnect is happening, and are just adopting a defensive posture. Why not be honest with us, and help us to better understand, in your own words, why objects like KSN 2015K and sn1987a cannot be considered the cosmic version of laboratory z-pinches? What physical features -- not just assumptions -- actually precludes such an analysis? An honest assessment would really help to advance the conversation.
....our Sun is not the brightest.
Neither are any of the mentally challenged that kneel before the genitalia of the cult of EU.
Finally, a simple explanation for Brexit.
It must have been something you assimilated. . . .
our Sun is not the brightest.
shudders, remembering how often parents said that
We live in very interesting times, where things -- like electricity -- which are extraordinarily mundane down here on Earth are apparently just completely preposterous in the context of space.
Setting aside the fact that the existence of mathematics does not somehow make it correct, it is absolutely misleading to assert that there is no mathematics associated with either electrical cosmology (for example here) or the Electric Universe (for example here). In fact, understanding both require a deep appreciation for the Lorentz Force and Maxwell's Equations. Mathematics has been a part of electrical cosmology from its inception (for example here).
Math is crucial for understanding the critical ionization velocity effect; it has been used to show how Marklund convection can replace gravitational accretion as a system for forming stars (and unlike the idea of stars accreting gravitationally, the geometry matches observations of actual stars forming all at once in a burst). Don Scott could not have accurately predicted the structure of AGN jets without significant amounts of mathematics. He's a retired EE professor, so he has spent his life immersed in these mathematics which you claim the EU does not include.
Attempts to model space without electrodynamic plasma physics concepts are destined to fail. We know this because it's already been tried, and the approach has failed to explain the nature of the many cosmic plasma structures we observe.
Think about it this way: What is the first plasma we encounter as we leave the Earth? It's the ionosphere. You may not know a whole lot about the ionosphere, but if you've been paying attention at all, you will at least understand that it is layered. You might spend some time thinking about why that is. Why should differing concentrations of charge exist in layers at all? Why not just a smooth gradient of charge that tapers off as one leaves Earth? Why should differing, adjacent regions of charge not neutralize one another?
The math here explains why.
In a 1992 paper titled, "Double Layers Do Accelerate Particles in the Auroral Zone," the authors plainly state:
Observations of laboratory plasmas have shown that double layers are what lend plasmas their structure. When you see a plasma filament in a novelty plasma globe, you should be asking: Why is charge confined to this thin filament? Laboratory plasma physicists point to the double layer as the source of this structure.
You should also be asking these same types of questions about the Van Allen Radiation belts: How can it be that these belts have all of this
Carl Sagan:
Koberlein admits 4 years later that he was wrong to claim that the Electric Universe predicts no neutrinos, but take a look at the link you posted: He has left the claim there in his personal blog, without any mention of the mistake. Not only does he refuse to have his critiques reviewed, but when he is informed of obvious mistakes, he also refuses to retract those mistaken claims. This is the process which you are supporting by passing along his links. I'm always amused that people who claim to believe so strongly in the value of peer review will gladly point to unreviewed critiques so long as they personally agree with the claims being made.
Re: "The electric force travels faster than the speed of light with near-infinite velocity."
You've completely misstated this point, to the point of causing confusion. What Wal has suggested is that electrons have subparticles (he calls them "subtrons"). It is the subtrons which are interacting at near-infinite velocity and which confer quantum physics' mysterious attributes (absolutely not the electric force, which of course results from electrons -- not subtrons). Using this approach, it also becomes possible to explain gravity as a form of electron dipole distortion, much like what we already know about how the Van der Waals force works. This approach offers us a possible way to reconcile the quantum and gravity domains -- a problem which you of course fail to mention in your attempt here to discredit the EU. Their only crime here is to try to solve the problem that you fail to mention -- a problem which you will still be stuck with if you remove the EU from the conversation.
But, it's also incorrect to state that this constitutes their "central thesis". The central thesis is the conversation which we've been having here about how to model cosmic plasmas. When engaging these topics, its crucial to start there, because if you talk to people who consider themselves to be adherents, they will not place a whole lot of importance on subtrons, and you may also run into people who engage the EU topics, but who do not necessarily agree that all aspects of Relativity are wrong. Just like in mainstream physics, to the extent that people are thinking for themselves, you're going to observe a full spectrum of beliefs -- some better put together than others, of course.
Yeah, how dare people discuss the idea that electricity flows through space in a tech forum? And no less, in regards to a mission whose purpose is to resolve "burning questions -- and some sizzling mysteries -- about the orb of hot plasma that lights up our Solar System". Nevermind the fact that the inverse corona temperature enigma is a mystery for the vey reason that it's power source is claimed to come from its core; I mean, we should leave it up to the scientists to come up with "a complex system of plasma, magnetic fields, and energetic particles" to explain how it can be that the farther we get from the power source, the higher the temperatures become.
Re: "The few predictions it can make have been shown to be wrong"
As I've stated in another thread here, you are blocking the best explanation we currently have for the observed layering of cosmic plasmas. A person need only go to the first nearest plasma to Earth -- its ionosphere -- and you will immediately run into the unavoidable problem of explaining how it can be that the different regions exist as layers which do not recombine or mix. In other words, why do plasmas exhibit structure with well-defined edges, where plus and minus charge can coexist without apparently recombining to form neutral matter? Your insistence that the cosmic plasmas are not behaving as laboratory plasmas blocks the most scientific explanation we have for layering in plasmas: the double layer.
Your insistence that Relativity must be right ignores the conflict which existed long before the Electric Universe ever came onto the scene -- one of the problems which the EU actually tries to solve -- that quantum mechanics is irreconcilable with Relativity. One or the other (or both) will need to undergo significant changes in order to create an internally consistent modern physics worldview. The treatment of theorists who are attempting to find such novel solutions (without rigid adherence to the existing theories) as somehow heretical would seem to entrench modern science into this irreconcilable state forever. There can come a point where defense of scientific theories becomes defense against innovation in the sciences.
Re: "Relativity works. There has been no experiment where it has had a negative outcome."
Entire books have been written on this topic, but the most important reason why your statement misleads is because you are referring to the accuracy and precision of the equations, whereas the actual debate on these matters has always been over the physical inference.
None of these people are adherents of the Electric Universe, yet they are all saying the same thing.
The Thunderbolts Project has decided to cover Slashdot readers' rejection of the mainstream astrophysical acknowledgement of electricity in space in their ongoing Space News Youtube series.