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We are all waiting for these discussions to happen.
Lets see how long this takes.
I think this is extremely important to the Apollo shielding question as it casts serious doubts on the role of aluminium in protecting the astronauts. In fact, it seems the aluminium had the potential to make the radiation environment MORE hazardous.
The range of photonic energies emitted by the system can be adjusted by changing the applied voltage, and installing aluminum filters of varying thicknesses. Aluminum filters are installed in the path of the X-ray beam to remove "soft" (non-penetrating) radiation. The number of emitted X-ray photons, or dose, are adjusted by controlling the current flow and exposure time.
So unless you think you're smarter than Dr. Blakely, I think this pretty much proves the aluminium shielding was not the most appropriate material to use.
Rough approximations of some values announced by Van Allen show that an unshielded man would receive a dose of millions of rads
per hour in either of the belts. Fatal dose for a man is 500 rads per hour...
A projected shielding of 10 grams per centimeter would protect a man from... the outer belt's lighter particles.
Protection from the heavier, more energetic particles of the inner belt would probably require more shielding.
The energy of those particles is so high that no reasonable amount of shielding reduces the dose significantly because of the enormous number of secondary particles generated in the shield
Originally posted by DJW001
reply to post by FoosM
I repeat: now that we all agree that the knowledge now exceeds that of 1961: why are there no pictures of the Apollo missions loitering in near Earth orbit?
Did NASA take the risk?
They still had to find a way to get passed a million rads produced per belt.
The radiation plan for the Apollo lunar mission calls for low-altitude earth orbits and rapid transit to the moon to keep the Van Allen belt radiation dose below 1 rad.
The Solar Particle Alert Network (SPAN) (Fig. 5) monitors solar flares and associated radio emissions
on a 24-hour basis.
Originally posted by theability
reply to post by FoosM
Did NASA take the risk?
They still had to find a way to get passed a million rads produced per belt.
Here you about your incorrect numbers:
The radiation plan for the Apollo lunar mission calls for low-altitude earth orbits and rapid transit to the moon to keep the Van Allen belt radiation dose below 1 rad.
Source
Plus this also said about detection capability:
The Solar Particle Alert Network (SPAN) (Fig. 5) monitors solar flares and associated radio emissions
on a 24-hour basis.
Below one rad, no problem whatso ever.
Next Let us talk about the shield they had on Apollo Missions it was called the Service Module.
As noted here:
[atsimg]http://files.abovetopsecret.com/images/member/4c8c97c8cb09.jpg[/atsimg]
How many more feet of shielding do you need. I'd imagine 40,000lbs of liquid gases would suffice in the absence of water now right?
Feet of cryogenic fluids, aluminum, radiator fluid. Wow I don't think there would be an issue with adsorbing all that energy now would there? I mean 30 feet plus of material is way more than enough.
Originally posted by DJW001
reply to post by FoosM
I repeat: now that we all agree that the knowledge now exceeds that of 1961: why are there no pictures of the Apollo missions loitering in near Earth orbit?
Originally posted by theability
reply to post by FoosM
Did NASA take the risk?
They still had to find a way to get passed a million rads produced per belt.
Here you about your incorrect numbers:
The radiation plan for the Apollo lunar mission calls for low-altitude earth orbits and rapid transit to the moon to keep the Van Allen belt radiation dose below 1 rad.
Source
Plus this also said about detection capability:
The Solar Particle Alert Network (SPAN) (Fig. 5) monitors solar flares and associated radio emissions
on a 24-hour basis.
Below one rad, no problem whatso ever.
Several instances of popular etymology are attested from ancient authors. Thus, the Greeks most often associated Apollo's name with the Greek verb απολλυμι (apollymi), "to destroy".[4] Plato in Cratylus connects the name with ἀπόλυσις (apolysis), "redeem", with ἀπόλουσις (apolousis), "purification", and with ἁπλοῦν (aploun), "simple",[5] in particular in reference to the Thessalian form of the name, Ἄπλουν, and finally with Ἀει-βάλλων (aeiballon), "ever-shooting". Hesychius connects the name Apollo with the Doric απέλλα (apella), which means "assembly", so that Apollo would be the god of political life, and he also gives the explanation σηκος (sekos), "fold", in which case Apollo would be the god of flocks and herds.
Source en.wikipedia.org...
Their plan for going rapidly through the belts.
How fast was that?
Originally posted by FoosM
books.google.com...=onepage&q=van%20allen%20belt%20rad&f=false
These conclusions (10) may be summarized as follows:
1) Flight below the Van Allen belts seems reasonably safe without radiation shielding.
2) It is probably impractical to shield a rocket sufficiently to permit a man to remain in the inner Van Allen belt for more than about an hour, but it should be possible for him to go through it without serious harm.
3) Shielding for the outer Van Allen belt is possible but would have to be quite heavy if a stay of more than a few hours were contemplated.
4) The primary cosmic radiation is not intense enough to deliver a serious radiation dose, even for exposures of a few weeks, and the heavy cosmic ray primaries do not seem to present an unusual hazard.
Originally posted by nataylor
Originally posted by FoosM
books.google.com...=onepage&q=van%20allen%20belt%20rad&f=false
I just want to point out that you reject actual data from spacecraft as irrelevant, but seem to unquestioningly accept the "rough approximations" in a portion of a summary of an article.
If you go look at the actual article that summary was written about, you'd find this:
Limitations on Space Flight due to Cosmic Radiations
These conclusions (10) may be summarized as follows:
1) Flight below the Van Allen belts seems reasonably safe without radiation shielding.
2) It is probably impractical to shield a rocket sufficiently to permit a man to remain in the inner Van Allen belt for more than about an hour, but it should be possible for him to go through it without serious harm.
3) Shielding for the outer Van Allen belt is possible but would have to be quite heavy if a stay of more than a few hours were contemplated.
4) The primary cosmic radiation is not intense enough to deliver a serious radiation dose, even for exposures of a few weeks, and the heavy cosmic ray primaries do not seem to present an unusual hazard.
Since you accept the "rough approximations" in that article, can we also assume you accept the conclusions of the article that it's possible to traverse both belts "without serious harm?"
Limitations on Space Flight due to Cosmic Radiations
Curtis
Science 3 February 1961: 312-316.
DOI:10.1126/science.133.3449.312
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