The recent article, "NASA Likely to Break Radiation Rules to Go to Mars," see link, gives an overview of the radiation hazards a manned Mars mission will encounter.
Excerpt: “Based on current knowledge, astronauts on a mission to Mars would exceed NASA’s career radiation dosage limits. Although the Agency plans to continue efforts to develop countermeasures to address the radiation risk, NASA is likely to seek an exception from the current standards for those that cannot be fully mitigated.”
Deep-space radiation in the form of galactic cosmic rays is deadly to humans. The Sun's massive magnetic field deflects most such GCRs away from Earth; however the Sun's magnetic field is weakening. NASA has various satellites "up there" that monitor such things.
And, if death is not the immediate result, several other debilitating illnesses or diseases result: ". . . cancer-inducing radiation can also cause cardiovascular and degenerative diseases—like cataracts, premature aging, and endocrine problems—a risk “of much greater concern than previously believed.” It can also rejigger the central nervous system, screwing with everything from cognition to spatial perception to hand-eye coordination. Then there’s the infertility, the cataracts, the slow wound healing, and the problems that astronauts could pass on to future children if they make it back from the long trip to Mars and manage to procreate."
SLB has a few earlier articles on a manned Mars mission,
"Mars Colony - A Bad Idea" see link
A portion of "A Week That Was July 2016" - excerpted below:
o A serious doubt for the future of manned space exploration re-surfaced this past week, with evidence and a report that lunar astronauts suffer (and some have died) from much higher incidence of cardio vascular disease; almost none of the non-flying astronauts, nor the low-earth orbit astronauts have this; the explanation is exposure to intense deep-space radiation and ionizing high-energy particles (galactic cosmic rays) by those astronauts that flew past the Earth's Van Allen Belts and went to the moon. This has deep implications for the proposed moon-orbiting manned space station, any manned Mars missions, and especially a Mars colony. The long-term orbiting astronauts on the International Space Station provide valuable data on some medical aspects of space life, but that is all within the protective shield of the Van Allen Belts. see link to Nature article on deep-space radiation effects on astronauts, "Apollo Lunar Astronauts Show Higher Cardiovascular Disease Mortality: Possible Deep Space Radiation Effects on the Vascular Endothelium"
Roger E. Sowell, Esq.
copyright (c) 2017 by Roger Sowell - all rights reserved
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