Post by JayUtah on Apr 9, 2010 16:40:18 GMT -4
I've read the book. The hoax authors badly misquote and misrepresent Mauldin.
First and foremost, Mauldin accepts the validity of the Apollo missions and contrasts that engineering with what would be required for an interstellar spacecraft. Anyone who wants to argue that Mauldin's findings preclude a successful Apollo mission must deal with the fact that Mauldin believes Apollo was real.
Second, Mauldin is indeed talking about a specific kind of space voyage: a generation ship operating at velocities of around 0.3c for perhaps hundreds of years in interstellar space. He is not talking about short voyages to the Moon. The principal radiation source that concerns Mauldin (or rather, his hypothetical voyagers) is galactic cosmic radiation endured over an entire human lifetime outside the heliopause. GCR in interstellar space is a more energetic source of radiation than cislunar space during solar quiescence.
Second-order sources of radiation include solar activity in and around solar systems, and the induced radiation of the spacecraft moving at high speed through low-energy particles, creating high energy collisions. This is why the Enterprise has a deflector dish.
Because most of these sources persist for the lifetime of the crew, the attenuation must necessarily be aggressive. The attenuated dose rate should not exceed normal background radiation for a planetary dweller. Hence a generation mission has a much more stringent requirement for radiation attenuation than a 10-day mission conducted by persons designated as radiation-hazard workers for occupational purposes.
Mauldin discusses the shielding thickness in one portion of the book and shielding material in another part, so it's not clear what substances his "two meters" of shielding might be made of. Mauldin diagrams several shielding strageies, but does not give precise engineering design information.
What is clear, however, is that Mauldin intends his exercise to apply only to the type of mission he describes in the book, not to any space mission regardless of environment or constraints.
First and foremost, Mauldin accepts the validity of the Apollo missions and contrasts that engineering with what would be required for an interstellar spacecraft. Anyone who wants to argue that Mauldin's findings preclude a successful Apollo mission must deal with the fact that Mauldin believes Apollo was real.
Second, Mauldin is indeed talking about a specific kind of space voyage: a generation ship operating at velocities of around 0.3c for perhaps hundreds of years in interstellar space. He is not talking about short voyages to the Moon. The principal radiation source that concerns Mauldin (or rather, his hypothetical voyagers) is galactic cosmic radiation endured over an entire human lifetime outside the heliopause. GCR in interstellar space is a more energetic source of radiation than cislunar space during solar quiescence.
Second-order sources of radiation include solar activity in and around solar systems, and the induced radiation of the spacecraft moving at high speed through low-energy particles, creating high energy collisions. This is why the Enterprise has a deflector dish.
Because most of these sources persist for the lifetime of the crew, the attenuation must necessarily be aggressive. The attenuated dose rate should not exceed normal background radiation for a planetary dweller. Hence a generation mission has a much more stringent requirement for radiation attenuation than a 10-day mission conducted by persons designated as radiation-hazard workers for occupational purposes.
Mauldin discusses the shielding thickness in one portion of the book and shielding material in another part, so it's not clear what substances his "two meters" of shielding might be made of. Mauldin diagrams several shielding strageies, but does not give precise engineering design information.
What is clear, however, is that Mauldin intends his exercise to apply only to the type of mission he describes in the book, not to any space mission regardless of environment or constraints.