This article by A.M. Jorgensen of the New Mexico Institute of Mining and Technology's Electrical Engineering Department, S.E. Patamia from the Space Instrumentation and System Engineering department of the Los Alamos National Laboratory and B. Gassend from the Massachusetts Institute of Technology was published online 24 October, 2006 on Science Direct and will appear in Acta Astronautica, Volume 60, Issue 3, February 2007, Pages 198-209.
A precis of the abstract follows. Full text access to this article is available for US$30 upon registration with Science Direct.
The Earth's natural van Allen radiation belts present a serious hazard to ... travel on [a] space elevator. The average radiation level is sufficiently high that it can cause radiation sickness, and perhaps death, for humans spending more than a brief period of time in the belts without shielding.
The exact dose and the level of the related hazard depends on the type or radiation, the intensity of the radiation, the length of exposure, and on any shielding introduced.
For the space elevator the radiation concern is particularly critical since it passes through the most intense regions of the radiation belts.
Apollo astronauts [travelling through the belts] received radiation doses up to approximately 1 rem over a time interval less than an hour. A vehicle climbing the space elevator travels approximately 200 times slower than the moon rockets did, [resulting] in an extremely high dose up to approximately 200 rem under similar conditions, in a timespan of a few days [and may also affect] technological systems on the space elevator.
[This paper gives] an overview of the radiation belts in terms relevant to space elevator studies ... compute[s] the expected radiation doses and evaluate[s] the required level of shielding.
[The authors] concentrate on passive shielding using aluminum, but also look briefly at active shielding using magnetic fields.
[They] also look at the effect of moving the space elevator anchor point and increasing the speed of the climber. Each of these mitigation mechanisms will result in a performance decrease, cost increase, and technical complications for the space elevator.
Labels: Space elevator, Van Allen radiation belt