Conservation of energy is Nature's version of the 'balanced budget'. It is also much more rigorously enforced that the human financial version.
In Nature, you can occasionally engage in some deficit spending, but only for a very short time (via the Uncertainty principle, see UVa: The Energy-Time Uncertainty Principle: Decaying States and Resonances). Because we know these conservation laws are rigorously enforced, the Patent Office automatically rejects any device proposed for patent that tries to violate it, such as perpetual motion machines (Wikipedia: Perpetual Motion:Patents).
One method popular among scientists and engineers when examining systems is to explore their power requirements, also known as their energy budget. If power requriements to run a system dramatically exceed the available power sources, the system is unworkable. Many a scam has been perpetrated on scientifically naive consumers (see AGU Blog: The Latest Perpetual Motion Fraud) and investors (see NY Times: There's One Born Every Minute) with the notion of energy from nothing.
Conservation of Energy raises one of the major questions for any hypothesis of stars being powered by external sources:
Where does the energy come from?
Now there is one prime candidate as a possible exterior energy source for the Sun and other stars - cosmic rays. Cosmic rays consist of energetic charged particles - electrons as well as protons and heavier ions, that seem to approach the Earth roughly uniformly from all directions.
This is the largest source of energy moving towards the Sun, so the obvious question is:
How Much Power Can Come from Cosmic Rays?
And the related question:
Is there enough energy in incoming cosmic rays to power a star?
To determine this energy, we need to know the particle flux, number of particles striking the surface per time, and the amount of kinetic energy carried by each particle. We'll assume the energy comes from the kinetic energy of the particle rather than the full mass-energy which would require matter-antimatter annihilation. A good starting point for information about cosmic rays would be the Cosmic Ray entry on Wikipedia.
We can do a simple estimate of the power available using the measured energy flux of cosmic rays at the orbit of Earth (assuming they were all directed towards the Sun, which they are not) using the basic equation for power and some dimensional analysis:
Power = Energy per time
= (Energy per particle) * (number of particles per area per time) * area
It is a little more complex than this because cosmic rays have a range of energies and there are a different number of particles at each energy. This is represented by a spectrum as seen on the wikipedia page.
However, because the flux of cosmic rays is roughly constant at low energies and then decreases at higher energies, we can probably get a reasonable estimate. There are occaionally very high energy cosmic rays, but these are very rare and contribute little to the TOTAL power in cosmic rays. In space, we'll use the measured particle flux of about
20,000 particles/m^2/s = 2e4 /m^2/s for energies of 1 GeV
(1 GeV = 1 billion electron volts). This value will cover most of the cosmic-ray population. As noted above, at higher energies, the flux (number of particles per area per second) decreases rapidly, so they will probably make only a small contribution to the total power available.
Since we are measuring these particles from a detector at Earth orbit, to get the total number of particles heading towards the Sun, we need to multiply by the area. The area needed in the calculation is the area of the spherical surface defined by the earths orbit. We'll make the simplifying assumption that all the particles crossing the orbit of Earth inbound towards the Sun converge on the Sun.
Using the radius of the Earth's orbit as 1 Astronomical Unit (149e9 meters) and the area of the sphere as 4*pi*r^2, we find:
Area of surface = 4*pi*(149e9 m)^2 = 2.79e23 m^2
Now we complete the computations
Power = 1 GeV * (2e4/m^2/s) * 4*pi*(149e9 m)^2
= 1e9*1.6e-19 J * (2e4/m^2/s) * 4*pi*(149e9 m)^2
= 1.6e-10J * (2e4/m^2/s) * 2.79e23 m^2
= 8.93e17 Watts
With the solar luminosity of 3.84e26 Watts, we see that the incoming cosmic rays have only
(8.93e17 Watts) / (3.84e26 Watts) ~ 2e-9.
Cosmic rays can provide only 2 billionths of the energy needed to power the Sun!
This is the inbound particle population we can detect, and it is woefully insufficient for the task of powering the Sun.
So where are all these incoming particles EU 'theorists' claim can power the Sun?
How do they hide?
One popular EU excuse is it's a 'dark current'. But 'dark current', in the plasma community, is an archaic term left over from the days when experimenter had to rely on their eyes as the detector. 'Dark current' meant there were particles moving through the region, they just didn't emit visible light. Such 'dark currents' can be detected by their emission in wavelengths beyond visible light, or by particle detectors. This excuse is not applicable.
Exercise for Readers:
From the cosmic ray review at the Particle Data Group, the cosmic ray spectrum above 1 GeV can be approximated by
I(E) = 1.8e4 (E/1GeV)^-alpha nucleons/m^2/s/sr/GeV
where the power-law index, alpha, is equal to 2.7.
Compute a more accurate power from cosmic rays by integrating over the spectrum over the energy range. How does it compare to the estimate above? Hint: it's still not enough to provide a substantial part of the solar luminosity.
Historical Note: In the late 1800s, before we knew about nuclear energy, it was actually hypothesized that infalling meteorites would provide some energy for the Sun.
Sunday, July 28, 2013
Sunday, July 21, 2013
(Non-) Electric Universe News for Summer 2013
Magnetic Reconnection
More observational evidence for magnetic reconnection in energetic solar events
and also other observations, courtesy of Solar Dynamics Observatory (SDO)
Note the reconnection animation at the bottom of the page. The magnetic field is NOT static.
Additional References
Some mainstream researchers still use the term 'discharges' when discussion the electric fields and current flows generated by magnetic reconnection, which EU supporters have seized upon to claim the researcher is actually talking about a discharge similar to lightning. I recently wrote about how this is in error (see On Magnetic Reconnection and "Discharges" as well as my section on magnetic reconnection in The Electric Sky - Short-Circuited).
IBEX Contradicts Electric Sun Models AGAIN!
The IBEX mission, which measures the flux of NEUTRAL ATOMS (not ions, not electrons) moving near Earth, seems to have detected the action of the fast and slow components of the solar wind interacting with the interstellar medium along the Sun's heliotail (Wikipedia: heliosphere). The interaction has provided a distinct signal for the heliotail of the Sun - the 'downwind' component of the heliosphere as it moves through the interstellar medium. The news is not that the heliotail structure exists - that has been suspected for years. The news is that we are seeing components (some expected, some unexpected) of it for the first time.
I've written before on how IBEX creates problems for an externally-powered 'Electric Sun':
Still more results showing how the solar neutrino problem was solved by neutrinos changing type as they travelled from the core of the Sun to the Earth. This result further reinforces the data of how the Sun is powered by INTERNAL nuclear reactions, not external electric currents.
And while mainstream science has plenty of published estimates of the neutrino flux for the standard solar model (Standard solar models, helioseismology, and solar neutrinos), we've yet to see a single estimate or even algorithm to compute the solar neutrino flux for ANY of the Electric Sun models.
Guess the Electric Sun supporters will have to continue to rely on innuendo to discredit the neutrino experiments since they have no facts…
When You Can't Win, Rewrite the Dictionary!
As the Electric Unverse advocates keep up their intellectual acrobatics trying to twist modern space science press releases into support for their model, they are running into more and more problems. I had written about some possibilies they might do as a 'Plan B' to rescue their struggling pseudo-science (see Whines of the Electric Universe. II.).
I'm finding examples on a variety of science forums where EU supporters, outside their safe zone of the Thunderbolts Forum, occasionally encounter knowledgeable amateurs and people who REALLY do science in space. When the Electric Universe supporters get cornered on the consequences of their more bizarre claims (as outlined in Challenges for Electric Universe 'Theorists'), they retreat to the claim that they are really correct because they believe gravity is actually an electric phenomena (see Thunderbolts: Article 16 : Implications of the electrical explanation of mass and gravity – Part 1).
More observational evidence for magnetic reconnection in energetic solar events
and also other observations, courtesy of Solar Dynamics Observatory (SDO)
Note the reconnection animation at the bottom of the page. The magnetic field is NOT static.
Additional References
- Wikipedia: Magnetic Reconnection
- Reconnection Experiments at the Princeton Plasma Physics Laboratory
- Thunderbolts, 2004: The Myth of Magnetic Reconnection
- Thunderbolts, 2008: Cluster’s "Magnetic Reconnection" Data and the Big Picture
- Thunderbolts, 2008: Magnetic Reconnection – Reinventing the Wheel
- Thunderbolts, 2011: Article 4 : “No” to Magnetic Reconnection and “Yes” to Electrified Plasma
Some mainstream researchers still use the term 'discharges' when discussion the electric fields and current flows generated by magnetic reconnection, which EU supporters have seized upon to claim the researcher is actually talking about a discharge similar to lightning. I recently wrote about how this is in error (see On Magnetic Reconnection and "Discharges" as well as my section on magnetic reconnection in The Electric Sky - Short-Circuited).
IBEX Contradicts Electric Sun Models AGAIN!
The IBEX mission, which measures the flux of NEUTRAL ATOMS (not ions, not electrons) moving near Earth, seems to have detected the action of the fast and slow components of the solar wind interacting with the interstellar medium along the Sun's heliotail (Wikipedia: heliosphere). The interaction has provided a distinct signal for the heliotail of the Sun - the 'downwind' component of the heliosphere as it moves through the interstellar medium. The news is not that the heliotail structure exists - that has been suspected for years. The news is that we are seeing components (some expected, some unexpected) of it for the first time.
- NASA: NASA’s IBEX Provides First View Of the Solar System’s Tail
- Phys.org: IBEX spacecraft images the heliotail, revealing an unexpected structure
I've written before on how IBEX creates problems for an externally-powered 'Electric Sun':
IBEX Results Cause Even More Problems for Electric Sun Model
"Electric Sun Verified"?? - In your dreams...
IBEX slams the Electric Sun model yet again...
The IBEX Challenge for the Electric Sun
Still more results showing how the solar neutrino problem was solved by neutrinos changing type as they travelled from the core of the Sun to the Earth. This result further reinforces the data of how the Sun is powered by INTERNAL nuclear reactions, not external electric currents.
And while mainstream science has plenty of published estimates of the neutrino flux for the standard solar model (Standard solar models, helioseismology, and solar neutrinos), we've yet to see a single estimate or even algorithm to compute the solar neutrino flux for ANY of the Electric Sun models.
Guess the Electric Sun supporters will have to continue to rely on innuendo to discredit the neutrino experiments since they have no facts…
When You Can't Win, Rewrite the Dictionary!
As the Electric Unverse advocates keep up their intellectual acrobatics trying to twist modern space science press releases into support for their model, they are running into more and more problems. I had written about some possibilies they might do as a 'Plan B' to rescue their struggling pseudo-science (see Whines of the Electric Universe. II.).
I'm finding examples on a variety of science forums where EU supporters, outside their safe zone of the Thunderbolts Forum, occasionally encounter knowledgeable amateurs and people who REALLY do science in space. When the Electric Universe supporters get cornered on the consequences of their more bizarre claims (as outlined in Challenges for Electric Universe 'Theorists'), they retreat to the claim that they are really correct because they believe gravity is actually an electric phenomena (see Thunderbolts: Article 16 : Implications of the electrical explanation of mass and gravity – Part 1).
With this re-writing of the dictionary, Electric Universe supporters make ALL results of mainstream astronomy become a consequence of their 'electrical' theories!
With this simple trick, the Electric Universe 'theorists' get to claim credit for other peoples' work while doing NO actual work themselves!
Sunday, July 14, 2013
Death by Electric Universe. Radiation Exposure Revisited
It recently came to my attention that some Electric Sun (ES) advocates have concocted an interesting excuse to 'rescue' their claims of an externally electrically-powered Sun (and stars) from the hazards created by the radiation environment of charged particles needed to power such a star. Most of these original articles are under the name Death By Electric Universe:
Most of 'justatruthseeker's supporting links are strangely irrelevant to the actual issue of the particle flux needed for an electric sun, diverting off into magnetic monopoles and magnetic shielding which have no relevance to the topic. This is a popular tactic of pseudoscientists and supporters to divert the discussion away from a point where they are clearly losing.
But back to the points claimed by 'JustATruthSeeker':
1) Spacecraft are shielded and so the astronauts are protected.
The major area of misunderstandings about the radiation environment created by an Electric Sun:
1) The high radiation environment of an electric sun is running continuously. This is not a case of heading for the heavy shelter for occasional events. The astronauts would have to be in the heavy shelter all the time.
2) The particle environment needed to power a star electrically is far higher than that created by any measured solar proton event - and again, is running continuously, not in episodes.
3) The shielding needed to protect astronauts in an electric sun environment is far larger than anything we've used before.
along with myths about radiation in general...
1) There is no 'all protecting' method of shielding from radiation that is practical. If there were, numerous problems in space flight such as human trips to Mars, and nuclear power generation and waste disposal, would not be problems at all.
2) Protection from radiation depends on amount of shielding and the type and amount of radiation. Shielding that is effective for the nuclear medicine division in your local hospital would be insufficient protection from the particle radiation of a solar flare for an orbiting astronaut or a nuclear worker.
As I have noted many times before, a successful model is defined as one where it can make numerical predictions (derived from more fundamental established principles) which can be matched to actual measurements. So let's get a better idea of what's happening by applying some numbers of the problem. I described the method of computing the radiation dose required for one model of an electrically-powered star in the previous article. At the orbit of the Earth, I obtained a radiation flux from just the electrons of:
Exposure Rate
(Note 1 rad = 0.01 sieverts)
Rads: 10.5 rads/s = 38,000 rads/hour
= 912,000 rads/day
Sieverts: 0.105 Sv/s = 105 mSv/s
= 380 Sv/hour
= 9,100 Sv/day
= 9,100,000 mSv/day
Since we are examining electrons, the Q-factor is one, so the biological effectiveness of the radiation, in REMS (wikipedia), is equal to the exposure in rads.
It is worth noting that these numbers represent the LOW limit of the radiation exposure as I have only used the incoming electrons, accelerated by the claimed billion-volt potential, in the calculation. If I included the outbound protons, also being accelerated by this potential, it would result in even higher radiation doses because protons have a higher biological effectiveness, Q-factor, than electrons. I'll leave that as an exercise for the reader - such a computation should be easily within the capabilities of a high-school physics student, but apparently beyond the capability of Electric Universe 'theorists'.
As also noted in the original article, we can define a limiting exposure above which our astronauts will suffer major health effects.
Above about 300 rads in one hour, you can expect serious health problems, and it gets worse with higher dosage.
Fatal dose 300 rads = 3 Sv = 3000 mSv
The radiation environment professionals have all kinds of strange units. One of the biggest difficulties in these analyses are making sure my units are consistent, and this is important (see Unit Mixups). Here's a few notes about the units used:
Explained: rad, rem, sieverts, becquerels: A guide to terminology about radiation exposure
1 gray (Gy) = 100 rad
1 rad = 10 milligray (mGy)
1 sievert (Sv) = 1,000 millisieverts (mSv) = 1,000,000 microsieverts (μSv)
1 sievert = 100 rem
1 becquerel (Bq) = 1 count per second (cps)
1 curie = 37,000,000,000 becquerel = 37 Gigabecquerels (GBq)
For x-rays and gamma rays, 1 rad = 1 rem = 10 mSv
For neutrons, 1 rad = 5 to 20 rem (depending on energy level) = 50-200 mSv
For alpha radiation (helium-4 nuclei), 1 rad = 20 rem = 200 mSv
Then there is also the question of what happens to spacecraft instrumentation (Solar Storms by Sten Odenwald).
Comparison of Electric Sun Particle Fluxes to the Actual Space Environment
Let's compare the electric flux needed to power the electric sun to some actual space environment measurements. As already noted in the original article, the flux and energies are far higher than anything we've measured from spacecraft anywhere in the solar system, including the Earth's radiation belts.
Note that the average exposure of all crews (shielded) amounted to between 0.26-2.1 mSv PER DAY (NASA: JSC-29295) from Project Mercury through Apollo and the Shuttle Program.
This is one millionth of the continuous radiation exposure required to power an Electric Sun (about 9 million milliSieverts).
In the next section, we'll start checking out the shielding requirements to reduce the exposure by an electric sun to the level experienced by flight crews.
The notion that the existing shielding on spacecraft are sufficient to protect astronauts from the particle environment of an electric Sun is looking like a pipe dream.
Shielding from an Electric Sun
Radiation exposure depends on particle flux (total number of particles passing through body) and energy of those particles. It is possible to reduce radiation exposure by increasing distance from the source, reducing the time of exposure, or increasing shielding shielding of sensitive hardware and crew.
Since we want to operate in space for significant durations of time, what kind of sheilding would be needed to protect astronauts from the radiation environments of an electric sun? How much shielding would be needed to reduce the unshielded radiation environment outside a spacecraft down to the level we've measured for astronaut exposure?
We want to reduce the radiation exposure from the EU particle environment from 912,000 rads/day to 2 rads/day, we must reduce the flux by a factor of 912,000/2.0 = 456,000, about half a million.
Since radiation absorption is a statistical process, we can compute the number of 'half-thicknesses' of shielding material needed to reduce the flux by this amount, 456000 = 2^n. Solving for n gives n = 18.8. Therefore, the total thickness of material we need is the half-thickness distance of the material, multiplied by about 19.
I'll use the halving thickness values in the table at Wikipedia: Radiation Protection. For lead, we see that the halving-thickness for gamma rays is 1 cm, and for steel, is 2.5 cm. Materials with lighter atomic numbers (such as those made into space suits) are not as effective. These will be useful reference values since gamma rays have the same Q value as electrons.
To reduce the radiation flux of an electric sun from 912,000 rads/day to 2 rads/day, we would need
(1cm) * 19 = 19 cm of solid lead
or
(2.5 cm) * 19 = 47 cm (almost half a meter or 1.5 feet) of solid steel
in a shell around the crew cabin.
That's significantly thicker, and heavier, than any spacecraft hull we've built to date!
Good luck getting that heavy thing off the ground!
(Still Unmet) Challenge for Electric Sun Advocates
'JustATruthSeeker', like so many other ES supporters, bizarrely uses the smaller actual radiation hazard as evidence that their model does not have a radiation problem.
The fact that space flight does not have this severe radiation problem is evidence that the particles and currents required to power an electric sun do not exist.
By what EU mysticism do all these electrons and protons become so undetectable, contrary to our laboratory experience? (The popular excuse of 'dark current' just means the effects are not visible in the optical range - radio, infrared, UV, x-ray or direct particle detectors are options).
The problem for Electric Sun supporters is that REAL space scientists run space weather models ROUTINELY to protect astronauts and other NASA assets around the solar system. Here's a snapshot from the continually updating projections generated at the NOAA Space Weather Prediction Center (SWPC)
These models don't have Electric Sun-powering 'currents' in them and yet provide fairly accurate predictions for event arrival time and particle flux needed to protect those satellites, all around the solar system. I've worked with these types of models propagated out to the orbit of Saturn.
Where are Electric Sun model runs for these events that we can compare to actual data?
Perhaps EUers want to invoke Excuse 6 above?
If Electric Sun supporters can't provide the algorithm for computing these predictions, then Electric Sun models are useless. This is the Electric Sun Epic Fail they evade talking about!
How about a more concrete, and simpler, practical example (mentioned in the earlier post, Death by Electric Universe. I. EU's Unsolvable Problem)…
A new mission called Solar Probe Plus (Wikipedia) is being built that will go on a trajectory sending it as close as 8.5 solar radii from the solar photosphere. Details of the radiation environment are vital for the successful operation of this mission. What kind of shielding does it need to be successful according to the Electric Sun model?
Electric Sun supporters like to claim their 'theory' of the Sun's operation solves all solar 'problems'. If Electric Sun supporters can't answer this basic question of how to shield the spacecraft, when the standard model of the solar wind can, then what good is their theory?
If Electric Sun supporters can't answer these fundamental question of practical implication for space flight, how can they claim their model is superior? Even more important, how can they be competent to be involved in a space program considering this affects the integrity of every satellite and the life of every astronaut?
What will be their excuse THIS time?
Update: July 21, 2013. Fixed a few typos
- Death by Electric Universe. I. EU's Unsolvable Problem
- Death by Electric Universe. II. The Solar Capacitor Model
- Death by Electric Universe. IV. The Z-Pinch (Solar Resistor) Model
- Excuse 1: But the spacecraft is shielded!
- Excuse 2: But Wait! Isn't the total radiated Photon Energy the same as the total Incoming Electron Energy?
- Excuse 3: What about those Drift Electrons?!
- Excuse 4: But a uniform population of drift electrons would be undetectable!
- Excuse 5: But Plasmas are Non-Linear!
- Excuse 6: We could do it if we had NASA's budget
- Excuse 7: It's not Important for Electric Sun Models
Most of 'justatruthseeker's supporting links are strangely irrelevant to the actual issue of the particle flux needed for an electric sun, diverting off into magnetic monopoles and magnetic shielding which have no relevance to the topic. This is a popular tactic of pseudoscientists and supporters to divert the discussion away from a point where they are clearly losing.
But back to the points claimed by 'JustATruthSeeker':
1) Spacecraft are shielded and so the astronauts are protected.
JustATruthSeeker: "And yet despite all your claims all spacecraft and spacesuits are heavily shielded against radiation so those astronaughts don't get fried, funny how that works huh? And apparently TB isn't aware of tests done."2) In the event of a particularly energetic event, there are shelters to provide more protection where the astronauts can safely 'ride out the storm'
JustATruthSeeker: "When in space and storms errupt, astronauts head to specially shielded rooms."There are numerous conceptual and physical errors in these excuses. One wonders if JustATruthSeeker even read the links they provided. As I will illustrate below, they clearly did not bother to check the numbers or the measurements, a common failure with crank science claims.
The major area of misunderstandings about the radiation environment created by an Electric Sun:
1) The high radiation environment of an electric sun is running continuously. This is not a case of heading for the heavy shelter for occasional events. The astronauts would have to be in the heavy shelter all the time.
2) The particle environment needed to power a star electrically is far higher than that created by any measured solar proton event - and again, is running continuously, not in episodes.
3) The shielding needed to protect astronauts in an electric sun environment is far larger than anything we've used before.
along with myths about radiation in general...
1) There is no 'all protecting' method of shielding from radiation that is practical. If there were, numerous problems in space flight such as human trips to Mars, and nuclear power generation and waste disposal, would not be problems at all.
2) Protection from radiation depends on amount of shielding and the type and amount of radiation. Shielding that is effective for the nuclear medicine division in your local hospital would be insufficient protection from the particle radiation of a solar flare for an orbiting astronaut or a nuclear worker.
As I have noted many times before, a successful model is defined as one where it can make numerical predictions (derived from more fundamental established principles) which can be matched to actual measurements. So let's get a better idea of what's happening by applying some numbers of the problem. I described the method of computing the radiation dose required for one model of an electrically-powered star in the previous article. At the orbit of the Earth, I obtained a radiation flux from just the electrons of:
Exposure Rate
(Note 1 rad = 0.01 sieverts)
Rads: 10.5 rads/s = 38,000 rads/hour
= 912,000 rads/day
Sieverts: 0.105 Sv/s = 105 mSv/s
= 380 Sv/hour
= 9,100 Sv/day
= 9,100,000 mSv/day
Since we are examining electrons, the Q-factor is one, so the biological effectiveness of the radiation, in REMS (wikipedia), is equal to the exposure in rads.
It is worth noting that these numbers represent the LOW limit of the radiation exposure as I have only used the incoming electrons, accelerated by the claimed billion-volt potential, in the calculation. If I included the outbound protons, also being accelerated by this potential, it would result in even higher radiation doses because protons have a higher biological effectiveness, Q-factor, than electrons. I'll leave that as an exercise for the reader - such a computation should be easily within the capabilities of a high-school physics student, but apparently beyond the capability of Electric Universe 'theorists'.
As also noted in the original article, we can define a limiting exposure above which our astronauts will suffer major health effects.
Above about 300 rads in one hour, you can expect serious health problems, and it gets worse with higher dosage.
Fatal dose 300 rads = 3 Sv = 3000 mSv
The radiation environment professionals have all kinds of strange units. One of the biggest difficulties in these analyses are making sure my units are consistent, and this is important (see Unit Mixups). Here's a few notes about the units used:
Explained: rad, rem, sieverts, becquerels: A guide to terminology about radiation exposure
1 gray (Gy) = 100 rad
1 rad = 10 milligray (mGy)
1 sievert (Sv) = 1,000 millisieverts (mSv) = 1,000,000 microsieverts (μSv)
1 sievert = 100 rem
1 becquerel (Bq) = 1 count per second (cps)
1 curie = 37,000,000,000 becquerel = 37 Gigabecquerels (GBq)
For x-rays and gamma rays, 1 rad = 1 rem = 10 mSv
For neutrons, 1 rad = 5 to 20 rem (depending on energy level) = 50-200 mSv
For alpha radiation (helium-4 nuclei), 1 rad = 20 rem = 200 mSv
Then there is also the question of what happens to spacecraft instrumentation (Solar Storms by Sten Odenwald).
"damage to sensitive electrical components becomes a problem at about 30,000 rads, considerably more than a satellite would accumulate in a typical 10- to 15-year lifetime."Note that in the radiation environment needed to power an electric sun, you exceed this amount of radiation in less than an hour if the effective target area of your electronics was equivalent to the size of a human!
Comparison of Electric Sun Particle Fluxes to the Actual Space Environment
Let's compare the electric flux needed to power the electric sun to some actual space environment measurements. As already noted in the original article, the flux and energies are far higher than anything we've measured from spacecraft anywhere in the solar system, including the Earth's radiation belts.
Note that the average exposure of all crews (shielded) amounted to between 0.26-2.1 mSv PER DAY (NASA: JSC-29295) from Project Mercury through Apollo and the Shuttle Program.
This is one millionth of the continuous radiation exposure required to power an Electric Sun (about 9 million milliSieverts).
In the next section, we'll start checking out the shielding requirements to reduce the exposure by an electric sun to the level experienced by flight crews.
The major transient events which endanger satellites and astronauts, the reason why we build extra shielding for long-term missions, are solar flares which can launch significant particle events, and coronal mass ejections (CME). Just how much radiation exposure can we expect from these types of events? Checking some references, we can get a few estimates.
- Forecasting Solar Energetic Proton events (E > 10 MeV)
- Wikipedia: Solar Proton Events
- Sickening Solar Flares
- Sickening Solar Flares. II. January 20, 2005 solar flare. 50 REM would have been absorbed by an astronaut in space suit from this single event. This was one of the largest measured events at the time, yet the exposure is still less than what you would get from an electric sun in less than ten seconds!
- NASA Technical Paper 2869: Solar-Flare Shielding with Regolith at a Lunar-Base Site. The August 1972 flare, provided a 500 REM unshielded dose over several hours, about 100 REM/hour. At an Electric Sun continuous rate of 38,000 rads/hour, we see even this flare's radiation would be lost in the radiation of an Electric Sun.
The notion that the existing shielding on spacecraft are sufficient to protect astronauts from the particle environment of an electric Sun is looking like a pipe dream.
Shielding from an Electric Sun
Radiation exposure depends on particle flux (total number of particles passing through body) and energy of those particles. It is possible to reduce radiation exposure by increasing distance from the source, reducing the time of exposure, or increasing shielding shielding of sensitive hardware and crew.
Since we want to operate in space for significant durations of time, what kind of sheilding would be needed to protect astronauts from the radiation environments of an electric sun? How much shielding would be needed to reduce the unshielded radiation environment outside a spacecraft down to the level we've measured for astronaut exposure?
We want to reduce the radiation exposure from the EU particle environment from 912,000 rads/day to 2 rads/day, we must reduce the flux by a factor of 912,000/2.0 = 456,000, about half a million.
Since radiation absorption is a statistical process, we can compute the number of 'half-thicknesses' of shielding material needed to reduce the flux by this amount, 456000 = 2^n. Solving for n gives n = 18.8. Therefore, the total thickness of material we need is the half-thickness distance of the material, multiplied by about 19.
I'll use the halving thickness values in the table at Wikipedia: Radiation Protection. For lead, we see that the halving-thickness for gamma rays is 1 cm, and for steel, is 2.5 cm. Materials with lighter atomic numbers (such as those made into space suits) are not as effective. These will be useful reference values since gamma rays have the same Q value as electrons.
To reduce the radiation flux of an electric sun from 912,000 rads/day to 2 rads/day, we would need
(1cm) * 19 = 19 cm of solid lead
or
(2.5 cm) * 19 = 47 cm (almost half a meter or 1.5 feet) of solid steel
in a shell around the crew cabin.
That's significantly thicker, and heavier, than any spacecraft hull we've built to date!
Good luck getting that heavy thing off the ground!
The bottom line is JustATruthSeeker's notion that astronauts could be protected from the radiation environment of an Electric Sun is, a best, a fantasy.
(Still Unmet) Challenge for Electric Sun Advocates
'JustATruthSeeker', like so many other ES supporters, bizarrely uses the smaller actual radiation hazard as evidence that their model does not have a radiation problem.
The fact that space flight does not have this severe radiation problem is evidence that the particles and currents required to power an electric sun do not exist.
By what EU mysticism do all these electrons and protons become so undetectable, contrary to our laboratory experience? (The popular excuse of 'dark current' just means the effects are not visible in the optical range - radio, infrared, UV, x-ray or direct particle detectors are options).
The problem for Electric Sun supporters is that REAL space scientists run space weather models ROUTINELY to protect astronauts and other NASA assets around the solar system. Here's a snapshot from the continually updating projections generated at the NOAA Space Weather Prediction Center (SWPC)
These models don't have Electric Sun-powering 'currents' in them and yet provide fairly accurate predictions for event arrival time and particle flux needed to protect those satellites, all around the solar system. I've worked with these types of models propagated out to the orbit of Saturn.
Where are Electric Sun model runs for these events that we can compare to actual data?
Perhaps EUers want to invoke Excuse 6 above?
If Electric Sun supporters can't provide the algorithm for computing these predictions, then Electric Sun models are useless. This is the Electric Sun Epic Fail they evade talking about!
How about a more concrete, and simpler, practical example (mentioned in the earlier post, Death by Electric Universe. I. EU's Unsolvable Problem)…
A new mission called Solar Probe Plus (Wikipedia) is being built that will go on a trajectory sending it as close as 8.5 solar radii from the solar photosphere. Details of the radiation environment are vital for the successful operation of this mission. What kind of shielding does it need to be successful according to the Electric Sun model?
Electric Sun supporters like to claim their 'theory' of the Sun's operation solves all solar 'problems'. If Electric Sun supporters can't answer this basic question of how to shield the spacecraft, when the standard model of the solar wind can, then what good is their theory?
If Electric Sun supporters can't answer these fundamental question of practical implication for space flight, how can they claim their model is superior? Even more important, how can they be competent to be involved in a space program considering this affects the integrity of every satellite and the life of every astronaut?
What will be their excuse THIS time?
Update: July 21, 2013. Fixed a few typos
Sunday, July 7, 2013
On Magnetic Reconnection and "Discharges"
There is a popular misconception, mostly among supporters of Electric Universe (EU) claims, that solar flares and similar eruptive events in plasmas are discharges much like terrestrial lightning or an arc furnace.
To support this claim, they often resort to papers by James Dungey, one of the pioneers in the study of the Earth's magnetosphere, who used the term 'discharge' when discussing one of his particular ideas of solar and magnetospheric eruptive events. The popular papers to cite in this case are
In the abstract of the 1953 paper, Dungey writes:
Dungey even uses the 'frozen-in' approximation, which I sure would infuriate EU advocates.
This is reinforced in Dungey's other papers on this topic:
Our early understanding of magnetic configuration associated with these eruptive events dated from less than a decade earlier (see Magnetic and Electric Phenomena in the Sun's Atmosphere associated with Sunspots) when Giovanelli began to examine the magnetic configuration around sunspots. Dungey also cites this work. What is amazing about the Giovanelli paper is that modern analyses solving the full Maxwell equations and plasma equations in this region have very little difference with the graphics in this early paper. From these initial observations of magnetic fields, combined with application of electromagnetic theory to sunspots came the recognition at a null point (a location where the magnetic field magnitude drops to zero) can form between two magnetic fields. By Maxwell equations, such null points can only form when the magnetic field around them forms a 'X' configuration.
A Discharge By Any Other Name
To add to the confusion with Dungey's word choice, the term 'discharge' has a much older history from the early days of plasma physics which developed from laboratory experiments with gas tubes and arc furnaces as well as observations of terrestrial lightning. In these cases, a discharge corresponds to a dielectric breakdown in a neutral gas under an externally applied electric field.
But solar flares cannot be a 'discharge' in this sense. The solar atmosphere is almost completely ionized and therefore quickly shorts any strong electric field unless that field is created in the plasma configuration itself. In this type of environment, such a 'discharge' cannot occur. Since solar flares and geomagnetic storms did not occur by this electrical breakdown process, the use of the term 'discharge' for these cases has been discouraged to improve clarity of the discourse. When discussing Dungey's model, some researchers would write 'discharge' in quotes to clarify the distinction between Dungey's use of the term and the classical definition of a discharge (see The Motion of Magnetic Field Lines by D. Stern).
In spite of these differences, one occasionally encounters a researcher who uses the term 'discharge' when describing the current flow in the reconnection region.
"X" Marks the Spot
As mentioned above, one of the common characteristics in observations of solar flares was the existence of a magnetic null point near the location of the observed flare. This null point would divide the region up into four zones, forming an 'X'-shaped configuration, as noted above.
If it were just a static magnetic field in a vacuum or in air, according to Maxwell's equations, it would be of little interest. But let that magnetic field vary in time, and according to Maxwell's equations, you'll get an electric field. Put this configuration in a plasma, even a neutral plasma, with equal numbers of positive ions and negative electrons, and all kinds of interesting things start to happen. Some Electric Universe supporters erroneously claim that magnetic reconnection occurs in a static magnetic field, which is incorrect. Often, Electric Universe supporters don't even mention that reconnection with energy release can only occur when the field is imbedded in a plasma.
Embedded in an electric field, the positive ions and negative electrons begin to move in opposite directions (the electrons much faster due to their smaller mass). The magnetic field also imparts an additional gyroscopic motion on the particles as they move, electrons with a very small orbit radius, ions with a much larger orbit radius. But these motions create a feedback system…
According to Maxwell's equations, distributions of charges and currents create electric and magnetic fields. According to the Lorentz equation, electric and magnetic fields accelerate charges, changing their motion. This acceleration is the source of the high energy charged-particles detected from reconnection sites.
Now there's a problem, because it is very difficult to mathematically model the behavior of lots of charged particles in electric and magnetic fields, especially when the particles themselves are contributing to the fields controlling their motion. Theorists try to make the problem manageable by abstracting the more complex, small-scale motions into approximations that can be described with some simple parameters.
One of the few methods which can generate an electric field and current in a predominantly neutral plasma is a null-point in a magnetic field - AKA, an X-point or "magnetic reconnection" (Wikipedia, from Plasma Physics Lectures at UT, Scholarpedia). Without reconnection, one must face the problem of how to generate the charge-separation in a neutral plasma to generate an electric field.
Some problems were found with the details of Dungey's description and mathematical model with observations, which are summarized by Heikkila in some papers:
What's in a Name?
This is also an example of how scientific terminology (like regular language) changes with time. When we discovered that chemical elements could change with the emission or absorption of some radiation or particle, we didn't understand what was going on, so we called it "transmutation of the elements". As we learned about the inner constituents of the atoms, and how the nucleus was the important component of these processes, the terminology changed to 'nuclear decay', 'nuclear reactions', and nucleosynthesis. "Transmutation of the elements" is today considered archaic and generally used in historical writing.
Yet some scientists can get really hung up on the terminology, forgetting that it is the underlying physical process that is important - not what we call it. Some researchers prefer the use of 'magnetic merging' (see Theoretical models of magnetic field line merging. I), those this term has not caught on in the research community.
Others put 'magnetic reconnection' in quotes to signify the analogy of reconnecting lines is not meant to be taken too literally. Either way, the physical framework of the magnetic field configuration has remained pretty much unchanged for over fifty years.
"Magnetic reconnection" is another example of a 'place holder' term which we use while we try to learn the details of what's going on. Historically, the neutrino was a place-holder from 1933 when it was first proposed, to 1954 when it was actually detected (Wikipedia). Today, "Dark Matter" and "Dark Energy" are place-holders in cosmology while we learn more about the phenomena. (ArsTechnica: Insert here: the role of placeholders in science ). Some of these place-holders get renamed as their underlying process is better understood, as happened for 'transmutation of the elements' described above. Other disappear into obscurity as they are identified as data collection biases, such as the K-effect in stellar radial velocities from the early 1900s.
When physicists use the term 'magnetic reconnection', it covers a wide variety of conditions. The magnetic field configuration and the presence of a plasma are common components, but many of the details, such as the plasma's resistivity/conductivity, diffusivity, composition, etc. become the details addressed in different reconnection models. These differences determine the speed and energetics of the reconnection event.
The bottom line is that Dungey's paper is NOT support for solar and magnetospheric energetic events being physically analogous to terrestrial lighting or arc discharges.
To support this claim, they often resort to papers by James Dungey, one of the pioneers in the study of the Earth's magnetosphere, who used the term 'discharge' when discussing one of his particular ideas of solar and magnetospheric eruptive events. The popular papers to cite in this case are
- J. W. Dungey. Conditions for the occurrence of electrical discharges in astrophysical systems. Philosophical Magazine Series 7, 44:725–738, 1953.
- The Neutral Point Discharge Theory of Solar Flares. a Reply to Cowling's Criticism
- Remarks on the Discharge Theory of Flares
In the abstract of the 1953 paper, Dungey writes:
It is shown that discharges are unlikely to occur anywhere except at neutral points of the magnetic field.But digging through the text reveals even more the error of interpreting this paper as support for terrestrial electric discharges like lightning. Dungey defines his term as
'discharge' as region where electrons accelerated to high energies by electric field so all electrons moving in same direction with high velocities.Dungey points out the problems involved in considering the discharge as due to an externally applied electric field (such as what occurs in terrestrial electric discharges). Figure 1 in Dungey's 1958 paper illustrates the classic magnetic reconnection configuration.
Dungey even uses the 'frozen-in' approximation, which I sure would infuriate EU advocates.
This is reinforced in Dungey's other papers on this topic:
Our early understanding of magnetic configuration associated with these eruptive events dated from less than a decade earlier (see Magnetic and Electric Phenomena in the Sun's Atmosphere associated with Sunspots) when Giovanelli began to examine the magnetic configuration around sunspots. Dungey also cites this work. What is amazing about the Giovanelli paper is that modern analyses solving the full Maxwell equations and plasma equations in this region have very little difference with the graphics in this early paper. From these initial observations of magnetic fields, combined with application of electromagnetic theory to sunspots came the recognition at a null point (a location where the magnetic field magnitude drops to zero) can form between two magnetic fields. By Maxwell equations, such null points can only form when the magnetic field around them forms a 'X' configuration.
A Discharge By Any Other Name
To add to the confusion with Dungey's word choice, the term 'discharge' has a much older history from the early days of plasma physics which developed from laboratory experiments with gas tubes and arc furnaces as well as observations of terrestrial lightning. In these cases, a discharge corresponds to a dielectric breakdown in a neutral gas under an externally applied electric field.
- The Theory of Collectors in Gaseous Discharges
- The Spectra of Gases Lighted with Strong Electrical Discharges
But solar flares cannot be a 'discharge' in this sense. The solar atmosphere is almost completely ionized and therefore quickly shorts any strong electric field unless that field is created in the plasma configuration itself. In this type of environment, such a 'discharge' cannot occur. Since solar flares and geomagnetic storms did not occur by this electrical breakdown process, the use of the term 'discharge' for these cases has been discouraged to improve clarity of the discourse. When discussing Dungey's model, some researchers would write 'discharge' in quotes to clarify the distinction between Dungey's use of the term and the classical definition of a discharge (see The Motion of Magnetic Field Lines by D. Stern).
In spite of these differences, one occasionally encounters a researcher who uses the term 'discharge' when describing the current flow in the reconnection region.
"X" Marks the Spot
As mentioned above, one of the common characteristics in observations of solar flares was the existence of a magnetic null point near the location of the observed flare. This null point would divide the region up into four zones, forming an 'X'-shaped configuration, as noted above.
If it were just a static magnetic field in a vacuum or in air, according to Maxwell's equations, it would be of little interest. But let that magnetic field vary in time, and according to Maxwell's equations, you'll get an electric field. Put this configuration in a plasma, even a neutral plasma, with equal numbers of positive ions and negative electrons, and all kinds of interesting things start to happen. Some Electric Universe supporters erroneously claim that magnetic reconnection occurs in a static magnetic field, which is incorrect. Often, Electric Universe supporters don't even mention that reconnection with energy release can only occur when the field is imbedded in a plasma.
Embedded in an electric field, the positive ions and negative electrons begin to move in opposite directions (the electrons much faster due to their smaller mass). The magnetic field also imparts an additional gyroscopic motion on the particles as they move, electrons with a very small orbit radius, ions with a much larger orbit radius. But these motions create a feedback system…
According to Maxwell's equations, distributions of charges and currents create electric and magnetic fields. According to the Lorentz equation, electric and magnetic fields accelerate charges, changing their motion. This acceleration is the source of the high energy charged-particles detected from reconnection sites.
Now there's a problem, because it is very difficult to mathematically model the behavior of lots of charged particles in electric and magnetic fields, especially when the particles themselves are contributing to the fields controlling their motion. Theorists try to make the problem manageable by abstracting the more complex, small-scale motions into approximations that can be described with some simple parameters.
One of the few methods which can generate an electric field and current in a predominantly neutral plasma is a null-point in a magnetic field - AKA, an X-point or "magnetic reconnection" (Wikipedia, from Plasma Physics Lectures at UT, Scholarpedia). Without reconnection, one must face the problem of how to generate the charge-separation in a neutral plasma to generate an electric field.
Some problems were found with the details of Dungey's description and mathematical model with observations, which are summarized by Heikkila in some papers:
- Critique of Fluid Theory of Magnetospheric Phenomena
- Magnetic reconnection, merging, and viscous interaction in the magnetosphere
What's in a Name?
This is also an example of how scientific terminology (like regular language) changes with time. When we discovered that chemical elements could change with the emission or absorption of some radiation or particle, we didn't understand what was going on, so we called it "transmutation of the elements". As we learned about the inner constituents of the atoms, and how the nucleus was the important component of these processes, the terminology changed to 'nuclear decay', 'nuclear reactions', and nucleosynthesis. "Transmutation of the elements" is today considered archaic and generally used in historical writing.
Yet some scientists can get really hung up on the terminology, forgetting that it is the underlying physical process that is important - not what we call it. Some researchers prefer the use of 'magnetic merging' (see Theoretical models of magnetic field line merging. I), those this term has not caught on in the research community.
Others put 'magnetic reconnection' in quotes to signify the analogy of reconnecting lines is not meant to be taken too literally. Either way, the physical framework of the magnetic field configuration has remained pretty much unchanged for over fifty years.
"Magnetic reconnection" is another example of a 'place holder' term which we use while we try to learn the details of what's going on. Historically, the neutrino was a place-holder from 1933 when it was first proposed, to 1954 when it was actually detected (Wikipedia). Today, "Dark Matter" and "Dark Energy" are place-holders in cosmology while we learn more about the phenomena. (ArsTechnica: Insert
When physicists use the term 'magnetic reconnection', it covers a wide variety of conditions. The magnetic field configuration and the presence of a plasma are common components, but many of the details, such as the plasma's resistivity/conductivity, diffusivity, composition, etc. become the details addressed in different reconnection models. These differences determine the speed and energetics of the reconnection event.
The bottom line is that Dungey's paper is NOT support for solar and magnetospheric energetic events being physically analogous to terrestrial lighting or arc discharges.
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