The conclusion that primordial heat is half the heat coming from the interior is pure speculation, since we don't have any workable models of planetary genesis. And no planetary scientist I talk to believes there is any way to account for the current heat of the core -- it's widely accepted that the current status contradicts the age of the earth. Hence the mystery.

Citation:
http://curiosity.discovery.com...

Anon,
If AGW is falsifiable, please provide an example of data that you would consider falsifies it. I've discussed AGW with many of it's scientist proponents, and they always say AGW can result in any conceivable data, including an ice age.

By dead cold I mean that no lunar-thermal heat reaches the surface. Mere compression brings the moon's core to 2,000F or so, but that's much lower than the Earth's peak of about 10,000F. The lunar surface is dead cold at -300F in darkness.

Care to cite a source for your claim of "half the heat"? I have an observable example in the moon for my position, with many measurements, which is presumed younger than the earth if you accept the collision theory of the moon's formation. Why is the earth so much hotter internally than the moon? It's a fair question that has no obvious answer.

When you survey the literature on geothermal heating, you find that friction is indeed _the_ major component of core heat. Especially tidal friction due to lunar gravity, which is far more significant that even meteor strikes, because it's a continuously varying force. But the physics of friction are well understood, and basic calculations show that friction is still not nearly a large enough source for measured temperatures and theoretical time spans.

In fact, radioactive heating was originally postulated as a source to make up for the inadequacies of frictional heating. But the magnitude of radioactive heating is orders of magnitude less than even frictional. As mathematicians would say, it may be "necessary, but not sufficient."

But we don't have a reasonable window. We literally have no data supporting the radioactive sustenance of the Earth's core temperature. Simple calculations demonstrate that radioactive decay is not adequate for the current age of the earth. Something has to give in a major way: either the earth is far less than even a million years old, or there is some other engine heating the Earth's core. Hell, for example ;)

When even scientists call it a mystery, that is pretty definitive that they don't know. Nobody calls solar fusion a mystery, because we can directly observe the process and there is no controverting data. It's a theory, to be sure, but valid until dis-proven.

But you can't say "scientists have a pretty good idea" about planetary formation. They have ideas. None has been shown to be even remotely "pretty good". In fact, they're all pretty bad, because they can be countered with mere calculation. A true scientist does due diligence on his own theories before publishing, but that process has gone by the wayside in recent years. Planetary accretion doesn't work because the kinetic energy of collisions is many times too great to permit particle coalescence as a function of gravitational attraction. That's undergraduate astronomy mathematics.

On the other hand, I could posit that planets are made on the Magrathea Factory Floor, and have as much evidence going for me as any other theory.

Bad example on your part. We can directly observe the Sun, and as you note, directly measure neutrinos. Still, solar fusion is just a theory, just one with no controverting data.

However, the planetary accretion processes cannot be directly observed. Yet the models do have controverting data, which I cited, in the form of reproducible calculations.

It's simply unreasonable to ever say we "know" a theory to be true when someone can demonstrate the impossibility or improbability of the theory, as has been done with all planetary evolution models to date.

"Scientists know' can be shorthand for 'the established scientific consensus allows us have a very high degree of confidence."
See, you're doing it right now! You don't want to say "We don't know." It sticks in your craw. Are you a scientist? ;)

Other euphemisms scientists often use for "We don't know":

"It isn't clear..."
"The best evidence indicates..."
"The consensus is..."

One thing no true scientist can forget: science is not a consensus enterprise. If one million scientists hold to a theory, and one scientists -- or even a non-scientist -- can provide reproducible calculations or experiment contradicting the theory, then the theory as posited must be discarded.

Moreover, to even qualify as a scientific theory, the theory must be falsifiable. Planetary accretion theories are falsifiable, as I've cited, but many other so-called scientific theories are not. Such as anthropogenic global warming (AGW) .

"The origin of the heat generated inside the Earth is one of the great mysteries of geophysics. Researchers know..."

Researchers don't "know" squat. They have lots of theories, none of which have supporting data. That's what makes the heat of the Earth's core a mystery. By all rights it should not be this hot. It should be dead cold like the moon.

In the 1800s, famed physicist Lord Kelvin (for whom the absolute Kelvin temperature scale is named) was the first to calculate that even if the earth was born in an incandescent molten state (and there is no evidence for this), it would have cooled to its current temperature billions of years sooner than the 4.6 billion years accepted today. Even using generous assumptions about the thermal energy produced by radioactive decay (which also have no direct evidence), the earth would still cool to its current temperature much sooner than 4.6 billion years.

A related mystery is how planets form at all. The conventional theory is that they "clump up" from smaller particles, eventually achieving enough critical mass form an accretion disk that gains heat from compression, gradually acquiring a gravitationally-optimal spheroid shape. But that model has been shown to be inadequate: "Growth beyond meter size via pairwise sticking is problematic, especially in a turbulent disk. Turbulence also prevents the direct formation of planetesimals in a gravitationally unstable dust layer."

So when someone says "scientists know", they are often flat out wrong, as is this story's author.

The three little words so many scientists are deathly afraid to say: "We don't know."

PRTG (paessler.com). This network management tool is not, strictly speaking, an IT appliance. But it might as well be, since it's trivial to install on a dedicated physical or virtual host, at which point it walks and quacks like any other IT widget. PRTG's interface makes extensive use of Ajax, real time charting, and sports an extremely logical organization that is both intuitive and powerful. It works equally well on desktop and mobile browsers, a rare treat for IT gear.

I think you missed something I noted earlier: the radar beam is directed energy, so it has a much stronger signal than the omni directional transponder response. Also, the radar station has immense amounts of power available to it, while the transponder is limited to the power available in the aircraft, which is notoriously limited. I don't have exact numbers right now, but the radar is putting out hundreds of watts, while the transponder is putting out perhaps five or ten watts maximum. The possibility that the omnidirectional, weaker transponder will be heard when the highly focused powerful radar isn't seems implausible. In my many years of aviation experience I've never seen it happen.

Everything electrical in the aircraft has to be under the control of the pilots in order to respond to emergencies. For example, an electrical fire might require shutting down the two busses carrying he redundant transponders. Or a generator failure might mean powering down non-critical equipment, which could easily be the transponder if the pilot is already near an airport and in radar contact. There is simply no practical way to protect most equipment from malicious onboard actors.

The ATC system would flag any transponder code change. That's been a security measure for decades, ever since the first hijackings back in the 1970s. In fact, there are special codes to indicate various emergencies that a pilot can dial in as a rudimentary alternate communications channel. Also, in addition to the code, all modern aircraft using Mode S also transmit a unique hard-coded aircraft serial number. That is difficult to change in flight, by design. Keep in mind that the airspace they were flying through was largely empty, so there is not a large chance of a controller mixing up flights. However, there is some chance, and there is always the possibility of conspiracy. But now you're talking tinfoil hat theories.

No, the transponder can't do that. Its signal is completely independent of the radar echo, on a different wavelength, and provides no independent position information. The radar echo arrives before the transponder reply, since both travel at the speed of light in air and the transponder response takes time to generate, while the echo is just an instantaneous reflection of microwave pulses. The signals are correlated by a ground computer to generate the controller display, which draws a symbol in place of the radar blip with the altitude data nearby, but that's just a presentation function. The computer also computes the aircraft ground speed and direction of travel and displays those numerically as well. The blips are all on screen, but deliberately dimmed to keep down screen clutter.

But BOTH raw radar data and transponder replies are recorded at the controller's station (actually by he computer, of course). This way aviation authorities can reconstruct exactly what the controllers saw on their screen. I worked on software for the original version of this system, which was written in the Jovial programming language and IBM basic assembly language (BAL). The software and computers have changed, but amazingly the radar system itself has evolved very little, other than wth the addition of more stations and better data collection networks.

The movie "Pushing Tin" (Angelina Jolie, John Cusack, Billy Bob Thornton) is actually a pretty accurate depiction of how it all works. Not a lot has changed since that movie was made. The movie's title comes from slang for what controllers still do today when they lose their computer capability and have to deal with just primary radar returns. They push little paper markers around on the screen and keep track of flight information with paper data strips, and that serves as the emergency backup mechanism in the event of a computer failure.

I'm a network engineer and know 802.11 well. Your analogy fails, because the radar signal is the main function of the system, which generates aircraft position information from which the system derives track and velocity. You completely dismissed this component and actually said it's rarely used in civilian aviation.

There is no parallel with WiFi. WiFi broadcasts are just data packets; radar interrogations are directional energy beams that locate aircraft in distance and azimuth. WiFi broadcasts are no different from the packets the client sends back to the AP: the framing, timing, and encoding is identical. But radar interrogations are tri-pulse trains on a common global frequency, with unique timing to identify the type of interrogation. Transponder replies are at a different common global frequency transmitted in as TDM-encoded data frames. Replies are omnidirectional and only pass data generated by cockpit instrumentation back to the radar station.

Thus transponder data is only used by controllers for identification and altitude, and some ancillary data. Mode S GPS content in transponder replies is used by other aircraft for TCAS, not by controllers for position information. If the aircraft is outside reflection range, it won't transpond. By definition if the transponder replies to an interrogation, it was because the aircraft was being painted by a radar's "skin" beam, which at microwave frequencies means there is line of sight between the aircraft and ground antenna. The radar echo is guaranteed to make it back to the station because of this line of sight. On an aircraft the size of a 777, very little energy needs to be reflected to generate position data, and I've never seen a situation where transponders don't have a corresponding primary radar blip.

All these differences between reality and your analogy lead to radically incorrect conclusions about system capabilities and behavior. I can say the earth is like and egg, because they're both round, but that doesn't make it a good analogy.