I'm researching the VA belts GCR's and SPE's in an attempt to understand the issue of thier affect on manned spaceflight better and I have recently come across the above mentioned phenomena..
Astronauts have reported seeing flashing lights in both Apollo spacecraft and in shuttles...could they have been due to Bremsstrahlung?

ChrisUK

<font size=-1>[ This Message was edited by: on 2003-02-07 14:56 ]</font>

Probably not. The "flashing lights" were most likely the result of cosmic rays (a term used loosely to include high energy particles as well) hitting the retinas of the astronauts' eyes. The flashing lights were not really lights at all but an artifact of that biological interaction.

No. Brehmsstrahlung is the emission of x-rays as an energetic electron is absorbed by a high atomic mass atom.

There is the simple retinal absorption theory you've already seen. There is also a minority theory: Dr. Ed Mitchell thought his flashes were blue, leading some to speculate about Cherenkov radiation.

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"Facts are stubborn things." --John Adams
Clavius Moon Base

Thanx guys....This info will go into my database....Although i do have information which suggests thst any time charged particles are accelerated or decellerated bremsstrahlung is emitted it is always a good thing to use several sources for info before coming to a conclusion....

<font size=-1>[ This Message was edited by: ChrisUK on 2003-02-07 16:47 ]</font>

And that information isn't inconsistent with what you saw here. It takes a high molecular weight substance to convert the particles' kinetic energy into x-rays - at least in any significant flux. But if x-rays were the source of the flashing lights, the mechanism by which that could occur isn't at all obvious - nor is it observable with medical x-rays.

I do see some merit to the Cherenkov radiation theory though. (Ed Mitchell isn't color blind is he?)

Which is why the apollo spacecraft would not have benefitted from lead sheilding while passing through the VA belts....the denser the material the more bremsstrahlung,which is x rays...which ar harmful to man in large quantities...now I get it!!

Debunking Dark Moon is gonna be easy!!!!!

Right, the degree of x-ray emission is proportional to the atomic weight of the material doing the slowing -- it could be lead, aluminum, or Frito crisps. So for shielding you want something that's dense (so it takes up a small volume) but you want it to be dense with hydrogen so that you get maximum stopping power with minimum braking mess.

Water is ideal, hydrocarbons are the most practical, and lead is monumentally stupid. It's stupid not because it won't do the trick; in sufficient thicknesses it will stop the particles and attenuate the x-rays. But because lead is so heavy, it's impractical for spacecraft when lighter materials work just as well or better.

High-density polyethylene is the material of choice. It's easy to work with, light, and packed with hydrogen.

(BTW, I'm the Clavius webmaster -- we corresponded earlier.)

__________________
"Facts are stubborn things." --John Adams
Clavius Moon Base

I can see it--the Apollo Frito-Lay^{<font size="-2">TM</font>} command module. Just don't eat away all of your shielding before you get back inside the Van Allen belts!
[img]/phpBB/images/smiles/icon_biggrin.gif[/img]

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<a name="JD2452679.Yy"> page JD2452679.Yy aka Yea? yuck
On 2003-02-08 05:15, David Hall wrote:
On Friday {around noon} the Japenesse kid
On 2003-02-07 23:29, JayUtah wrote:
sat B4 a couple of Ms {Intel innside}ERs
so I looked .. one Graph was _ the other /~
take your pick {i still have a 38620} & an IBM 8088 ALLso
anyway the interesting light was the background
darker yellow at the top fading to lighter
as the scan lines move down the page..
i did ask CrickShank if it was possible to send files
from 1 Ms To the other { YES? Later } see Summer$ Term

Thanx to all....most helpful indeed.

Chris

On 2003-02-08 06:19, HUb' wrote: To 1:50 A.M.1:50 A.M. HUb'
<a name="JD2452679.Y2y"> page JD2452679.Y2y aka Yea &yuck2
ok let me REtry
the TV set if viewed while listening to an AM
"RADIO" makes a good enough radioactivity detector.
because you can hear the click on the AM radio
and see the flash on the TV screen at the same instant
and their4 you can say with some certainty
{with a lots of practice} yes! there was a proton
or electron , alpha, beta. Gamma; a lot of junk
or something relevant. For these observations
both sets must be "ON" [and its best to be tuned off channel]
Ok my points this When the TVs turned off the phospher screen
still acts as an {insesitive} detector & would flash if hit by an energetic enough {whatever} It Does Not there for alls Quiet on the western front at 2:00 A.M. pst {BWUW}