J. White calculates why Apollo craft could not have survived passage through the VABs

a reply to: Rob48

Quite frankly I wouldn't even trust him to give me the correct change for my burger.

I see what you did there.

But I think you're being too generous!

a reply to: AlphaHawk

I actually wonder — and this is not just me being flippant or insulting — whether Jarrah may have a mild form of dyscalculia.

You can often hear him hesitate and stumble over the numbers he reads out, and on more than one occasion in his videos he transposes two digits when reading them, or writes them incorrectly. And you just don't get the feeling from hearing him read out the calculations that he actually understands quite why he is doing the steps he does.

Most tellingly, when his calculations lead to an obviously absurd result (millions of rads per hour, by the end of the video!) he doesn't seem able to intuit that something has gone awry. That is a classic symptom.

It would explain a lot, actually. Dyscalculia affects people of all IQ levels, and for all that I take the mickey out of Jarrah, he is clearly not a stupid man.

He can work his way round film editing software rather well, track down some fairly esoteric source material and deliver a script rather convincingly (to a layman) as though he knows what he is talking about. He just has a huge blind spot when it comes to maths.

a reply to: Rob48

Not spotting an absurdly high and inaccurate number is something that's seen all too often, I think it's more "OMG look, see I'm right, high numbers!1!"

The best are sample results that chemtrail believers drag up, like the ones from California skywatch a few years ago.

They completely botch it to the point of absurdity, you'd think when the results showed arsenic at levels hundreds of thousands of times the lethal dose, they'd go back to the drawing board...nope, publish it!

He also has a knack for quoting from books that prove him wrong, relying on a quick zoom-'n'-pan over the offending areas to zoom in on the bit he is cherry-picking. Fortunately, YouTube offers a slow-mo function!

Here, just after the 15 minute mark, we see an excerpt from Problems in Shielding of Space Vehicles, which is part of a book called Aeronautical Engineering and Science. Jarrah skims over the page to get the formula for Bremsstrahlung radiation, completely ignoring the passages that point out just how easily shielded the Van Allen Belt electrons are!



As the book says, while Bremsstrahlung is still a potential hazard, it can be minimised by using a shielding material with a low atomic number. Aluminium, with Z = 13, is ideal in this respect!

Further up the page, you can also see the estimates for radiation in deep space of only 25 rem PER YEAR!

So, Jarrah has admitted he screwed the pooch. But it's not his fault!

Many have wrote [sic] in to say that I made an error on steps 5 and 9. That I should have divided the number of Joules by the mass. True.

To my credits [sic] though, I used these exact same steps for a university assignment that I submitted last semester, in which I used Pioneer 10 data to calculate the dose rates from electrons in Jupiter’s radiation belt at the vicinity of Europa. In that assignment I multiplied the Joules by the mass to convert the Grays. The examiner did not mark me down for it.

He goes on to claim that even with the correct conversion, he still gets a dangerous dose.

This is because he seems to think that if electrons are present with energies between 10 and 100 MeV, that means the average energy is 55 MeV. When in fact the energy distribution will pretty much follow a smooth power-law curve.

He just doesn't get it!

Next question: who the heck is Jarrah's university examiner? Does anybody know where he is doing his much vaunted astrophysics course?

Indeed JW has updated his video
and corrected a mistake that Rob pointed out here on this thread.
But JW still maintains that his calculations show the radiation doses
would have been fatal for the Apollo astronauts.

And I am s till waiting to see if anybody has NASA's math to compare
his calculations to.

500 rad = 5 sieverts. So a 5 sievert dose is a death sentence.
According to the UN, the electron belt would provide a daily dose
of "thousands" of sieverts! How did Apollo Astros get through that without
any complications? Not even a little nausea?

a reply to: FoosM

They got through the VAB by using a trajectory that minimized the time they spent in it.

Here are some basic sums

spacemath.gsfc.nasa.gov...

Why couldn't you find them?

Source for your 'UN' value would be useful, but it shouldn't be too difficult for anyone to spot the difference between a 'daily dose' and 'dose received by a spacecraft travelling through in well under an hour'.

a reply to: FoosM


he is still assuming there is NO SHIELD.. and that ALL 10^6 and 2x10^6 particles have a charge of 10MeV.. which they dont..



Jarrah uses this picture himself.. yet he only considers the outer hull??

Jarrah is ignoring the insulation another sheet metal, another honeycomb and another sheet metal..

which means the apollo CM hull assuming its the same thickness all around will be about 4.68g/cm^2 NOT INCLUDING THE INSULATION, not including hardware, not including the CSM.. just a spherical double hull..

and this alone by using jarrahs argument would stop upto about 8.57MeV..

but jarrah just assumes that ALL electrons carry greater than 10MeV and that the flux density is 10^6 and 2x10^6.. which is again him twisting the numbers to suit his agenda..

and incase you missed it, his calculations still assume there is no shield, but still adds the bremsstraulung effect to again twist the numbers.. there is no bresstraulung when there is no shield, Jarrah needs to make up his mind.

ETA:


why did you, i mean Jarrah, assume that there would be a particle flux of 10^6 and 2x10^6 with charges of 55MeV??

if you read the whole sentence which jarrah got the information that its between 10-100MeV it says:

the high-energy electron belt is located further out than the two overlapping inner belts, and in the above figure it is colored purple. Electrons in THIS outer belt carry between 10 to 100 million volts of energy, on average.

coloured purple!! and it only extends to i believe about 3.6 earth radii.. but the flux that jarrah is using is the area that is 5-6 earth radii?? whats going on?? you are taking the energy levels of one area and using the flux of a different area?? WHY????

originally posted by: onebigmonkey
a reply to: FoosM

They got through the VAB by using a trajectory that minimized the time they spent in it.

That is not correct, NASA has admitted that at least one trajectories went through
the hottest zone.

originally posted by: onebigmonkey
a reply to: FoosM

Here are some basic sums

spacemath.gsfc.nasa.gov...

Why couldn't you find them?

Like I said in an earlier post in this same thread regarding that same link you provided...

Who would stake an astronauts life based on those basic calculations backed up by dubious and unsubstantiated
figures or claims?

originally posted by: FoosM

originally posted by: onebigmonkey
a reply to: FoosM

They got through the VAB by using a trajectory that minimized the time they spent in it.

That is not correct, NASA has admitted that at least one trajectories went through
the hottest zone.

Source, or you're making it up.

originally posted by: FoosM

originally posted by: onebigmonkey
a reply to: FoosM

Here are some basic sums

spacemath.gsfc.nasa.gov...

Why couldn't you find them?

Like I said in an earlier post in this same thread regarding that same link you provided...

Who would stake an astronauts life based on those basic calculations backed up by dubious and unsubstantiated
figures or claims?

You asked for the figures. You've been given them. Are they correct or not?

You asked for Jarah's mistakes to be explained, they have been.

Who would stake their lives? The astronauts themselves.

originally posted by: onebigmonkey
a reply to: FoosM


Source for your 'UN' value would be useful, but it shouldn't be too difficult for anyone to spot the difference between a 'daily dose' and 'dose received by a spacecraft travelling through in well under an hour'.

Please explain what you mean daily dose differences. And what are you talking about traveling under an hour?
You mean though one of the zones? Because it took Apollo longer than an hour too travel through both belts.
You are aware of that, right?

originally posted by: onebigmonkey

originally posted by: FoosM

originally posted by: onebigmonkey
a reply to: FoosM

Here are some basic sums

spacemath.gsfc.nasa.gov...

Why couldn't you find them?

Like I said in an earlier post in this same thread regarding that same link you provided...

Who would stake an astronauts life based on those basic calculations backed up by dubious and unsubstantiated
figures or claims?

You asked for the figures. You've been given them. Are they correct or not?

Nobody has given anything so far. That link you provided I ALREADY EARLIER POSTED.
I consider the info provided in that link crap. But maybe your standards are lower.

originally posted by: FoosM

originally posted by: onebigmonkey

originally posted by: FoosM

originally posted by: onebigmonkey
a reply to: FoosM

Here are some basic sums

spacemath.gsfc.nasa.gov...

Why couldn't you find them?

Like I said in an earlier post in this same thread regarding that same link you provided...

Who would stake an astronauts life based on those basic calculations backed up by dubious and unsubstantiated
figures or claims?

You asked for the figures. You've been given them. Are they correct or not?

Nobody has given anything so far. That link you provided I ALREADY EARLIER POSTED.
I consider the info provided in that link crap. But maybe your standards are lower.

and you dont think the numbers given by jarrah are crap???



since you need reminding.. jarrah uses the charge of 10-100MeV WHICH IS IN A COMPLETELY DIFFERENT AREA to the flux density used to calculate his radiation dosage..

WHY??

if he wants to use the 10-100MeV figure he needs to use the corresponding flux figures, which would be about 30 cm^2/s NOT 10^6 cm^2/s and NOT 2x10^6 cm^2/s.

a reply to: FoosM

You asked for NASA figures yet you already had them? Aaaah I see, you had them but you don't like them because they prove you wrong.

if you think they are wrong then provide your own. Your favourite source for such figures has been shown to be incompetent as a source, so I'd look elsewhere. Links and references are helpful.

As for how long they spent there, they didn't spend a day there, so they would not have received a day's worth of dose. Not too difficult is it?

Some argue 4 hours as a time from start to finish, but this is not the same as spending the whole journey in the most intense region, which would be considerably less. If you have an exact figure, provide it, with a reference, and then give us a calculated dose for that time period based on the different levels you would experience for the different regions.

If you want the best figures for actual dosage, I suggest you look at this:

history.nasa.gov...

and if you don't believe them, prove them wrong.

onebigmonkey:

Source, or you're making it up.

Isn't this something...

The inner belt, where many satellites must operate, is home to the most hazardous and energized particles, mostly protons. “A staggering number of the spacecraft we rely upon daily have to spend a part of their orbit in the harshest area of Earth’s radiation environment,” says Joseph Mazur of the Aerospace Corporation, Principal Investigator of the probes’ Relativistic Proton Spectrometer (RPS). The Van Allen Probes are providing researchers with detailed views of how the populations of those particles vary with altitude, which should help engineers more effectively protect satellites. “This is the first time we’ve been able to measure the high energy particles in the heart of the radiation belts,” Mazur said. “We’re able to measure at the one billion electron volt level; particles at that energy are virtually impossible to shield against. They will easily penetrate half-inch thick aluminum plate.” Particles at that energy level are known to cause a range of damages to spacecraft, from physical degradation to instrument malfunctions and false readings.

www.space.com...

One billion volts at the heart of the Van Allen Belts?
Stick that number in the calculations.
Radiation that can penetrate half inch thick aluminum PLATES easily?
Im sure nobody here will deny that Apollo craft couldn't attenuate enough radiation to protect the astronauts.

See, when NASA was figuring out the Belts back in the 60's, they simply didnt have the instruments or technology
to really accurately measure the VABs. Apollo missions were based on incomplete research.
So even a few minutes in that zone should have at least made them sick.

No shielding possible.... so
there is no difference if you are 10 seconds in the water or 10 minutes, you are wet the same.

originally posted by: onebigmonkey

Source, or you're making it up.

So now that we know that the heart of the VABs has
energies up into the billions Im hoping Rob, or anybody here
can do the calculation to show how much radiation exposure
Apollo astronauts would have received with the shielding they had
including their suits. Because a dose of a thousand sieverts is no joke.

I think if NASA knew how radioactive that area was, it would
be against the law for them to send astronauts through that field knowingly.

a reply to: FoosM

funny how you didnt highlight the keywords..

they are able to measure at the billion electron volt level.. they did not say that there were billion electron volt particles..

and even if there were the flux would be very low.. which is what you are still failing to understand.. flux and the charge of particles are inversely proportional..

but i still want to know, why did you take the charge of some particles from one area and the flux from another area to prove that the radiation was too high??


its like trying to prove scotland is overpopulated by using the total population of china and dividing by the total land area of scotland and using that as evidence that scotland is overpopulated.. get real.

a reply to: FoosM

Still no source for your original claim, and the link you provide doesn't actually contain the quote you provided.

This page does:

www.nasa.gov...

So. How long did Apollo astronauts spend in this inner belt?