[illustrative purposes only]
An improperly designed "study" by amateur scientists generated headlines worldwide:
“Cosmic Radiation Could Cause Alzheimer's in Mars Astronauts” ABC
“Astronauts and Alzheimer's: Mouse Study Shows Cosmic Radiation Is Associated With Disease" ABC News
“A mission to mars could damage astronauts' brains” Business Insider
“Study: Mars-Bound Astronauts Exposed To Heavy Radiation; More Likely To Have Alzheimer's"
“Mission to Mars Could Mess With Your Brain" Discovery News (LOL)
“Houston, we have another problem” Eureka Alert
“Can humans journey into deep space without cosmic radiation frying our brains?” iO9
“Space Flight Linked to Alzheimer's” News Max
"“Sad Science Fiction Plot Becomes Reality: Space Radiation Could Cause Alzheimer's" PopSci
“Does Deep Space Travel Cause Alzheimer's?" Smithsonian Blogs Surprising Science
“Technology News: Space: Alzheimer's Could Be the Trade-off for Deep-Space Pioneers” Tech News World
“Space Travel Could be Dealt a Blow with Discovery that Cosmic Radiation Could Cause Alzheimer's Disease" Cleveland Leader
“Cosmic radiation can cause Alzheimer's in astronauts: study” The Financial Express
A few questions:
1) who authorized this study
2) are they fired yet
3) is there a single j school grad capable of reading it?
"Galactic Cosmic Radiation Leads to Cognitive Impairment"... generates worldwide headlines, whereas "After a Single Acute Burst Exposure to an Accelerated Beam of Iron Nuclei at Three and a Half Months of Age Transgenic Mice Brains Predisposed to Alzheimer's Examined Only Four to Six Months Later Suffered Inflammation, with Males Showing Enhanced Plaque Pathology and Females Showing Absolutely None Whatsoever" might lead the public to question how close this poorly written study cloaked in jargon corresponds to actual humans exposed over six months to much smaller gradual increments of radiation. Specifically whether "These pathological increases are particularly concerning for astronauts who will be exposed to [Galactic Cosmic Radiation] in upcoming deep space missions" actually means Mars pioneers will suffer dementia, as so many scientifically illiterate journalists are now reporting. Low level six month exposures might be worse than a single burst, or, with proactive medical treatment might not be a concern at all. We do not know.......at the very least the next similar study ought to expose mice over a longer period of time to radiation at lower doses and not euthanize females two months early.
Months of low level cosmic radiation was supposedly compressed into a single meaningful 10 to 100 minute "acute dose"?
"...one major caveat of our model is that mice were subjected to acute exposures with a single HZE species [iron particle beam]. It is not known how the CNS [astronauts] will respond to the complex and chronic low-dose GCR [galactic cosmic ray] environment of space. Moreover, astronauts will not likely be familial AD carriers [genetically predisposed to Alzheimer's]. Therefore, while many of the pathological processes are believed to be similar, this model does not reflect the complete human condition."Intergalactic radiation is halved on the Martian surface and zero in habs buried beneath it. The only way to know whether humans can live on Mars is for us to go to there and strive to stay.
In the long term we may use water from asteroids to shield Earth-Mars cyclers, in addition to creating portable mini-magnetospheres: http://www.minimagnetosphere.org/
More information on the challenges of intergalactic radiation:
Much literature on radiation poisoning still uses the deprecated 'rad' unit of measurement. Readers may note these equivalences: 1 J/kg = 1 Gy = 100 cGy = 100 rad. 1 Sv = 100 rem. (Conversion from Gy/rad to Sv/rem depends on biological effect.) See also:
Apparently Slate is the only publication in the entire world with a journalist capable of deciphering this nonsense, Konstantin Kakaes:
"...basic flaw in the University of Rochester study is that it relies on subjecting mice to acute doses of radiation....
The researchers acknowledge these limitations in print, though they don’t seem to take their own caveats seriously: “Differences in mouse strain, timing, and radiation beam energy limit our ability to extrapolate from these studies,” they write at one point. They later continue, “while many of the pathological processes are believed to be similar, this model does not reflect the complete human condition.”
So headlines like “Study: Space Radiation Could Cause Alzheimer’s” are true in a narrow sense: Space radiation could cause Alzheimer’s. But this study doesn’t establish that it does. The real news here is that overreliance on mouse models continues, as does selective interpretation of data. In this study, significant changes in the amount of brain plaque thought to contribute to Alzheimer’s were seen only in male mice—but there’s little discussion of the fact that female mice appeared relatively unscathed. All of the mice had been genetically engineered to be susceptible to Alzheimer’s, something not likely to be true of astronauts. Even so, irradiated mice performed differently to non-irradiated mice in only two of three simplistic cognitive tests."http://www.slate.com/blogs/future_tense/2013/01/03/cosmic_radiation_may_give_astronauts_alzheimer_s_says_study_don_t_cancel.html
Thank you Konstantin for making an effort to publicize the flaws of this biased study. Yours is the only article I have yet found that does so. Bravo, good work.