Mars, the OAP Planet
MARS, the International Journal of Mars Science and Exploration, has just published two articles by Donald Rapp about the hurdles still to be clarified before sending astronauts to the Fourth Planet: “Mars life support systems” and “Radiation effects and shielding requirements in human missions to the moon and Mars”
The latter article contains sobering statements about the current status of space-travel technology (my emphasis):
For Mars missions, we conjecture a 400-day round trip transit to and from Mars, and about 560 days on the surface. The [Galactic Cosmic Radiation] dose equivalent with 15 g/cm2 of aluminum shielding during Solar Minimum is about double the allowable annual dose for each leg of the trip to and from Mars. If a major [Solar Particles Event] occurred during a transit, the crew would receive a sufficient dose to reduce their life expectancy by more than the 3% limit. […]
On the surface of Mars, the accumulated [Galactic Cosmic Radiation] exceeds the annual allowable [amount]. For a 560-day stay on Mars [it] would exceed the career allowable dose for most females and younger males.
May Richard Branson live looooooooong then (and prosper)!