Lunacy from Brussels

Pooh Bear wrote:
....

You might care to consider that humans will be 'fried' close to a nuclear
reactor.

Lead shielding will make a craft impractically heavy for space flight.



Here's the General Atomic lead and hydrocarbons shield design as
presented to NASA in 1964.

http://spacebombardment.blogspot.com...l-atomics.html


"According to recent studies of planetary
exploration requirements, this shielding is sufficient to attenuate the
probable solar-flare radiation to dose values similar to the 50 REM
allowed for propulsion. the total mission dose from both sources
was expected to be about 100 rem".

bombardmentforce wrote:

Pooh Bear wrote:
...

You might care to consider that humans will be 'fried' close to a nuclear
reactor.

Lead shielding will make a craft impractically heavy for space flight.


Here's the General Atomic lead and hydrocarbons shield design as
presented to NASA in 1964.

http://spacebombardment.blogspot.com...l-atomics.html

"According to recent studies of planetary
exploration requirements, this shielding is sufficient to attenuate the
probable solar-flare radiation

SOLAR FLARE !

to dose values similar to the 50 REM
allowed for propulsion. the total mission dose from both sources
was expected to be about 100 rem".

And that's supposed to be safe ?

Exposure (rem) Health Effect Time to Onset


5-10 radiation burns;
more severe as exposure increases.
changes in blood chemistry

50 nausea hours

55 fatigue

70 vomiting

75 hair loss 2-3
weeks

90 diarrhea

100 hemorrhage


http://www.epa.gov/radiation/underst...th_effects.htm

So you'll have one *very* sick crew !

Bloody brilliant !



Graham

http://www.epa.gov/radiation/underst...th_effects.htm
"Short-term, high-level exposure is referred to as 'acute' exposure."

the total mission dose from both sources

For the whole multi-month mission to Mars, not a short term exposure.

http://spacebombardment.blogspot.com...your-dose.html

About the same dose as seven years of ISS exposure or three years of
Mars surface exposure, toasty, but not deadly.

bombardmentforce wrote:

http://www.epa.gov/radiation/underst...th_effects.htm
"Short-term, high-level exposure is referred to as 'acute' exposure."

the total mission dose from both sources

For the whole multi-month mission to Mars, not a short term exposure.

http://spacebombardment.blogspot.com...your-dose.html

About the same dose as seven years of ISS exposure or three years of
Mars surface exposure, toasty, but not deadly.

Oh ! you mean it won't kill them outright ?

Very nice.

GO BOIL YOUR STUPID HEAD !


Graham

http://spacebombardment.blogspot.com...your-dose.html
About the same dose as seven years of ISS exposure or three years of
Mars surface exposure, toasty, but not deadly.

Oh ! you mean it won't kill them outright ?

Yes, and you thought it would, glad to be able to teach you a small
lesson.

bombardmentforce wrote:

http://spacebombardment.blogspot.com...your-dose.html
About the same dose as seven years of ISS exposure or three years of
Mars surface exposure, toasty, but not deadly.

Oh ! you mean it won't kill them outright ?

Yes, and you thought it would, glad to be able to teach you a small
lesson.

If you reckon a 100 rem dose of radiation is acceptable then you're even
more berserk than I first thought!

Graham

Pooh Bear wrote:

bombardmentforce wrote:



http://spacebombardment.blogspot.com...your-dose.html
About the same dose as seven years of ISS exposure or three years of
Mars surface exposure, toasty, but not deadly.


Oh ! you mean it won't kill them outright ?


Yes, and you thought it would, glad to be able to teach you a small
lesson.



If you reckon a 100 rem dose of radiation is acceptable then you're even
more berserk than I first thought!

Graham





It's a totally acceptable dose from a radiation safety point of view for
radiation workers to get 100 rems, as long as it is spread out over 20
years (allowed dose is 5 rem/yr). The time over which the dosage is
acquired is a critical factor. There are some places on this planet
where the does rate exceeds 2 rem/yr with no noticeable affect (total
lifetime dose 100 rems). Now, 100 rems acquired gradually over a few
years is not exactly desirable but it is not likely to kill you, at
least for a few decades. These sorts of doses are small compared to what
some cancer patients already have to cope with. Whether or not a person
will subject themselves to this sort of radiation will depend on several
factors, including the age of the subject (nobody lives forever) and if
they think the trip is worth the risk.

--
Chris M. Hall
Dept. of Geological Sciences
University of Michigan

Chris Hall wrote:

It's a totally acceptable dose from a radiation safety point of view for
radiation workers to get 100 rems, as long as it is spread out over 20
years (allowed dose is 5 rem/yr).

See the context !

" allowed dose is 5 rem/yr " - indeed and that should be regarded as an upper
limit.

Repeated exposure to radiation is not considered healthy.


Graham

Chris Hall wrote:

snip

if they think the trip is worth the risk.

To visit a dead rock ?

I 'm sure the sense of that is clear to all.


Graham

Pooh Bear wrote:

Chris Hall wrote:



It's a totally acceptable dose from a radiation safety point of view for
radiation workers to get 100 rems, as long as it is spread out over 20
years (allowed dose is 5 rem/yr).



See the context !

" allowed dose is 5 rem/yr " - indeed and that should be regarded as an upper
limit.

Repeated exposure to radiation is not considered healthy.


Graham






You seem to have ignored much of my post. It may not be considered
"healthy" but 20-30 rems spread out gradually over a year or so (the
rate you were talking about) isn't likely to be extraordinarily
dangerous either. Much less dangerous than traveling to Mars or the
Moon, for example.

--
Chris M. Hall
Dept. of Geological Sciences
University of Michigan