[LibWhacker]

Defeatist, anti-nuclear, leftist crap. Bring back Orion!

[ElkGroveDan]

Cosmic rays can be diverted the same way were are protect here on Earth, with a strong magnetic field around the ship. It could be turned of during short periods for communication.

The Luddites don't just play hacky sack in Star Trek movies, they are alive and well and living in America.

[Mister_Diddy_Wa_Diddy]

This allowance might get them to Mars or Venus, but not to Jupiter or Saturn.

What the heck are humans going to do on Jupiter or Saturn that robots can't do?

[LibWhacker]

Project Orion: Its Life, Death, and Possible Rebirth

We could, in principle, launch a ship the size of the USS Ronald Reagan, with a crew of thousands aboard, fully armored with heavy steel or lead plate, three foot thick, if needed. These ships could cruise to Mars in a matter of weeks, and to anywhere else in the solar system in a few months. Only liberal, scared-of-their-own-shadows girlie-men are preventing us from doing it. Think about that: girlie-men are preventing us! We must be scared of them. . . . Sorry, I'm p***ed that we'd let those losers block such a magnificient future for mankind.

[newgeezer]

To all my conservative friends who give a rat's rump about space travel, I send my heartfelt well-wishes for their endeavors, and trust they will fund their hobby with their own money, just as I fund mine with mine.

[BibChr]

But women are always in more danger than men because they ...are more susceptible to ...ovarian cancers.

'Way more, I'd speculate.

Though I'm neither a doctor, nor do I play one on TV.

Dan
Biblical Christianity BLOG

[DBrow]

This is 226 REM, or, assuming that a midsection CAT scan gives you 5 REM, about 45 CAT scans and as far as chest plates, more than 2000.

Typically there are minor blood changes seen at 50 REM whole body, and an acute dose of 300 is life threatening. If this analysis is correct, getting 226 REM over a year represents a serious dose.

Space radiation is difficult to shield. The low energy stuff, slow propons and electrons, get shielded easily. The high energy stuff generates braking radiation (bremsstrahlung) IN the shielding, so at some point doubling the shielding no longer cuts the radiation in half.

This is a factor in Shuttle and space station operations. While nuke plant workers are limited to an occupational dose limit of 5 REM annually and rarely come close to that, the limit for astronauts was increased to 15 so they can continue to fly. Astronauts get lots of radiation compared to nuke plant workers or medical isotope workers.

There are solutions- massive ship with an outer annulus of lunar rock or water is one, as is a lighter craft with a solar sail to reduce transit time.

http://www.space.com/scienceastronomy/radiation_evarm_020716.html

NASA's been thinking about this for a long time, but rarely discusses it as a problem- I'm guessing that they feel they'd lose support from the public given the average American's fear of ionizing radiation.

http://www.sirr.unina.it/Asi/collegamenti/Introduction/NASA/NASA_Strategic_Plan.pdf

[KansasConservative1]

I wear a foil hat around the house for just that reason. No cancer here.

[Bloody Sam Roberts]

"I do not see how the problem of this hostile radiation environment can be easily overcome in the future,"

Create a spacecraft that emulates the planet Earth by creating a large electromagnetic field that would act to deflect this radiation away from the crew compartment and other sensitive areas.

[EsmeraldaA]

Other side effects are: Nose bleed, Diarrhea, Vomiting, Headache, Dizziness and the uncontrollable urge to run wild with every full Moon

You cannot possible believe this is something they just noticed ? If it is; don't worry your pretty little head about it. There are older wiser people taking care (of the worrying anyway) of it already. And I am NOT trying to be offensive, if I was you would know for sure. :)

[Brett66]

Aargh, propulsion is the key, not shielding, if you decrease the transit times, you decrease the radiation hazzard.

If we had something like Orion, we could get to Mars in a month or two and we could layer the ship with considerable greater shielding as well as reducing the radiation hazzard inherent in long transit times.

All this article does is remind one of why chemical rockets are not a good technology for transport further than the moon. We really shouldn't plan on 3 year Mars missions in the future, but 3 month Mars missions will work.

[Thoro]

Helped by O'Brien, the FAA's Civil Aerospace Medical Institute in Oklahoma City investigated the radiation doses likely to be received by people on a 2.7-year return trip to Mars, including a stay of more than a year on the planet. The study estimated that individual doses would end up being very high, at 2.26 sieverts.

.01 Sieverts in 1 REM(Roentgen Equivalent in Man)
2.26 sieverts = 226 rem
annual radiation worker whole body exposure limit = 5 rem
annual non-radiation worker exposure limit = .1 rem
annual radiation worker eye lens exposure limit = 15 rem

So in essence, a Mars astronaut would recieve 45.2 years worth of occupational radiation in 2.7 years. Just for some perspective and to give that number a bit more meaning than "it causes a ton of cancer". Sounds like they're going to need a bit more half-value layers worth of lead.

[HangnJudge]

2.26 sieverts hmmmm... 226 Rads
whole body but slow gradual exposure

Referencing
http://www.uic.edu/com/uhrd/manual/section8/section8.html
Major radiation induced cancers are:
female breast
thyroid
lung
leukemia

35-49 years old = 2.1/10^6 persons/rad/year
US Normal is 160,000 cases/106 persons (16%) -- for all cancers
Calculator out.... 4.7%
But not corrected for mixed LET radiation as in space environment
Don't know how to correct for heavy nucleus cosmic ray encounters

For the Chance of A Lifetime to go to Mars

I'd go for it, no way to hold me back
Besides, much more likely to die in the attempt

[KevinDavis]

Wow a bunch Saganites, want space for their own personal playground at taxpayer expense..

[Chewbacca]

I will volunteer for a manned mission to Mars.
So what if I die from cancer in 20 or so years.
My name would become immortal as the first man on Mars.

We are all born terminally ill anyway, so might as well make something of the life we have.

[mercy]

Cosmic rays are killing all of us ... right now. The human body is self repairing. It just can't keep up with the ray bombardment.

Back when the 'firmament' was still in place folks lived hundreds of years.

[AntiGuv]

No biggie in the long run. If we can't solve the problem from one direction - properly shielding the spaceships - then we'll eventually solve it from the other: repairing the physical damage. Everyone seems to be fixated on the former, but the latter would be far more widely useful in any event.

[359Henrie]

Cosmic rays will keep democrats from thinking

[Doc Savage]

Let's send Jesse Jackson and Dirtbin!