|
Post by Cavorite on Nov 15, 2009 7:48:07 GMT -4
I'd have to say this crossed the line into outright trolling some considerable time ago. If it's degenerated into taking shots at someone's screen name then any pretense at fact finding has been abandoned.
|
|
|
Post by PhantomWolf on Nov 15, 2009 8:15:45 GMT -4
If you remember from your elementary or high school science class, radiation comes in varying strengths. The three types are alpha, beta, and gamma radiation. The energy particles associated with each have different energy levels. The best illustration is what materials they can penetrate. Alpha particle are the weakest. They can be easily blocked by a piece of paper or skin. Beta particles are stronger and can penetrate the skin. This is where we see the effects of radiation. It can strike DNA causing spontaneous mutations. However aluminum and other substances of similar density can deflect these particles. The strongest radiation particles of all are gamma particles. This is the most common type of radiation in space. Only the most dense substances can stop them and even then they are absorbed upon contact. If you remembered your high school physics you'd know there is no such thing as a Gamma particle. Gamma radiation is called Gamma Rays because they are electromagnetic waves, not particles (unless you want to get into the whole what is a photon argument.) Also the most common form of harmful radiation (since light is a form of radiation) in space is particle based, not wave based. The VA Belts are protons and electrons, in fact Gamma can't even exist in the belts since it carries no charge and so in uneffected by magnetic felds and thus passes directly through them, while Cosmic Rays, despite the name, are heavy neculi such as iron and even uranium. These are all Alpha particles. As you have noted in your little speel, Beta and Alpha are both rather weak penetrators and can be stopped fairly easily.
|
|
|
Post by randombloke on Nov 15, 2009 8:49:11 GMT -4
fm: "Blah blah blah "flares can't be predicted" blah blah" citation? Date of citation? As I recall, flares were at least somewhat predictable, with a range of a couple of days, back when Apollo was flying. "A few days" being plenty sufficient for a three day mission. It is of course wildly insufficient for an extended duration mission to Mars for instance, which is why a new set of radiation studies is being done on the interplanetary environment. Also, "unpredictable" is not the same as "unobservable" - flare maxima are preceded by visible surface activity on the Sun, from which approximate intensity and primary vectors can be derived. On such a warning, astronauts can be ordered into their radiation shelter. Of course, this is a misdirection on your part as flares have very little to do with VAB radiation, which is particulate in nature and derived primarily from the solar wind, a separate phenomenon. You want to challenge the 8 minute claim? Go ahead, or should I in the future cite you as and expert in this area? Would you care to first point out where I even mentioned 8 minutes? You asserted that "flares are unpredictable" I asked you for a citation and you resorted to pejorative insults. This is not conducive to discussion. I never once mentioned the 8 minute figure because, oddly enough, it has nothing to do with prediction. In fact I totally agree that it should take 8 minutes for electromagnetic radiation to travel from the Sun to Earth. But that's like answering "it takes five hours to fly from New York to London" when asked for the time of the next scheduled flight. Factually accurate, but utterly useless as an answer to the question asked.
|
|
|
Post by drewid on Nov 15, 2009 8:51:38 GMT -4
"All manned space flight attempts must steer clear of these two belts of radiation until adequate means of safeguarding the astronauts has been developed"
Which is what they did, they steered around them. They are a barrier, but they are a barrier you can bypass. The stuff you posted from Van Allen's paper does not contradict that, or anything else that has been posted.
Also you seem to be implying that Randombloke's statements are self-contradictory. They aren't
|
|
|
Post by fm on Nov 15, 2009 12:27:55 GMT -4
"All manned space flight attempts must steer clear of these two belts of radiation until adequate means of safeguarding the astronauts has been developed" Which is what they did, they steered around them. They are a barrier, but they are a barrier you can bypass. And you revealed this in your drawing?
|
|
|
Post by echnaton on Nov 15, 2009 12:33:30 GMT -4
"All manned space flight attempts must steer clear of these two belts of radiation until adequate means of safeguarding the astronauts has been developed" Which is what they did, they steered around them. They are a barrier, but they are a barrier you can bypass. And you revealed this in your drawing? Can you state specifically why you disagree wiht the statement that they can be bypassed.
|
|
|
Post by archer17 on Nov 15, 2009 12:49:54 GMT -4
fm was doing the troll two-step from the beginning IMO. No one can avoid the facts like he does by accident. Sifting through the garbage... VAB - fm, despite continually showing his ignorance regarding the belts, avoids the key issue here ---> he needs to conclusively demonstrate how the Van Allen Belts made the Apollo manned lunar missions impossible. He hasn't and ignores that these belts were skirted by the astronauts. Why? He has to. Not only does he pretend not to "get it" when folks here illustrate how Apollo addressed the VAB, he conveniently misses the vast amounts of online data available. This data runs the gamut from Apollo mission radiation exposure totals to simpler explanations of the flight trajectories that are geared to kids. Shielding - fm would have you believe that, despite the evidence to the contrary, only he has the smarts to know what shielding would be sufficient for the lunar missions. Solar flares etc - We are supposed to be impressed that fm knows that it takes 8 minutes for the sun's emissions to get here but that red herring is elementary school stuff that, as randombloke points out, doesn't really address what fm is trying to imply - which is that we are totally in the dark about potential CME events. This is just not true and it's not a coincidence that, once again, a lame claim like this lacks a linked-to attribution. What fm actually needs to do is show us that a massive life-threatening CME occurred during every Apollo mission, an event that would have had to kill the astronauts. The one thing that fm honestly "doesn't get" is that he's not really tweaking anyone's nose here, which I feel is his real motivation. Some woos are like that. Well, in case you missed it fm, folks here like to show what they know and slap around HBers. Ask 'em. By acting like you're 'stuck on stupid' the way you do you aren't doing yourself and/or other HB promoters any favors and, ironically, have actually made this thread a place where lurkers and even semi-regulars like myself learned about aspects of the missions that we didn't know before. This thread turned out to be quite interesting... and it's not because of you, it's in spite of you.
|
|
|
Post by fm on Nov 15, 2009 13:22:14 GMT -4
And you revealed this in your drawing? Can you state specifically why you disagree wiht the statement that they can be bypassed. Your drawings revealed that the VABs where not bypassed. NASA says they weren't bypassed. And I define bypass as not going through them at all. So what did you mean by bypass?
|
|
|
Post by Jason Thompson on Nov 15, 2009 13:30:52 GMT -4
I think those pictures are a good representation, right? So a 2D representation is fine when you use it in your arguments, but insufficient in ours? Give up the double standard, will you? The gamma and x-rays take 8 minutes, and their flux really isn't that high. The particle ejections take hours to days to arrive, and these are far more deadly. The electromagnetic part of the flare is the warning that the really dangerous stuff is on the way. It's not dangerous to us, of course, because it gtes trapped in the belts, but to a spacecraft within or beyond them they are potentially deadly. The only people who don't consider them solved are people like you without the understanding required to interpret them. [quote[I think both sides, hoaxers and non-hoaxers might be benefiting... dare I say - financially - by keeping these debates going.[/quote] I get no benefit from doing this whatsoever. Many hoax proponents clearly do, however, by selling books and videos on the subject.
|
|
|
Post by Jason Thompson on Nov 15, 2009 13:39:02 GMT -4
A small amount of lead shielding would reduce the dose to a supportable level.
He didnt say add aluminum shielding. He states LEAD. He didn't say lead was the only possible or appropriate shield. He simply mentioned it as a possible effective shield. Gamma radiation is electromagnetic, not particle based. [/b] [/quote] But not in the van Allen belts, and in the space beyond what is the flux density and energy of the gamma radiation? It may be the most common, but that is a meaningless non-quantitative statement. Arguments about radiation are meaningless without numbers, and given that the VAST amount of research done by agencies not limited to NASA on the radiation environment in space the fact that no-one seems bothered by this level of radiation speaks volumes. Yawn. Not to anyone who actually understands the problems. And since the highest radiation levels during a translunar flight are encountered in the belts, which consist of high energy particle radiation such as protons and electrons, there is your explanation for why lead was not used in the spacecraft.
|
|
|
Post by drewid on Nov 15, 2009 14:45:33 GMT -4
Can you state specifically why you disagree wiht the statement that they can be bypassed. Your drawings revealed that the VABs where not bypassed. NASA says they weren't bypassed. And I define bypass as not going through them at all. So what did you mean by bypass? By avoiding the sections that are dangerous and minimising the transit time by skimming the edges of the belts where the radiation is minimal, and by using appropriate materials to shield high energy particle hits. You seem to have this idea that as soon as you encounter radiation it's instantly fatal, and that there is a hard border that marks the difference between totally safe and very dangerous. If you went out in a very light drizzle planning to get into your car, which will take ten seconds, then you're not going to get very wet. If you're going for a five mile hike in a monsoon then you will. It's all still rain, still water falling from the sky, but the effects are totally different. Radiation is like that. You posted a diagram from the wikipedia entry on the belts, the av8p 1.0MeV diagram. There is another diagram in the same wikipedia article showing the 400MeV proton density, notice the difference. The orbit misses this higher energy level area completely. Right, back to the 1MeV diagram, look at the numbers. The diagram shows proton hits per cm 2 per second. The diagram starts at a contour of 1. That's one hit per cm 2 per second. The hot core of the diagram goes up to 2x10^7. That's 20,000,000 hits per cm 2 per second . Spot the difference.
|
|
|
Post by echnaton on Nov 15, 2009 16:27:56 GMT -4
Can you state specifically why you disagree wiht the statement that they can be bypassed. Your drawings revealed that the VABs where not bypassed. NASA says they weren't bypassed. And I define bypass as not going through them at all. So what did you mean by bypass? As has been said many times before. The most dangerous portions of the belts were bypassed. The less dense parts were traversed with adequate shielding. That is what many people have been saying in several different ways. Your attempt to place different words in our mouths is indicative of the difficulties in this whole conversation.
|
|
|
Post by fm on Nov 15, 2009 18:55:29 GMT -4
I think those pictures are a good representation, right? So a 2D representation is fine when you use it in your arguments, but insufficient in ours? Give up the double standard, will you? Its quite simple actually. Do you believe the VAB's drewid drew are true to scale to the size of the actual VAB's in relation to Earth? If so how so, if not, why not. Maybe you do, because when I look at your sketch, your VABs also seem rather small in comparison to the Earth. What did you exactly base your scale on?
|
|
|
Post by PhantomWolf on Nov 15, 2009 19:56:58 GMT -4
Since you seem to be the expert on what they should look like fm, how about you draw and we critic for a while.
|
|
|
Post by frenat on Nov 15, 2009 20:15:44 GMT -4
Does the exact scale really matter or are you just nitpicking to be more of a troll? My guess is the latter. It has been shown many ways now that regardless of the exact scale of the belts, it is possible to miss them or skirt the edges with the described orbit. Any more trolling you want to do?
|
|