It is anticipated that the report would accomplish the following objectives:

Provide a preliminary assessment of the radiation exposure impact to ISS assembly activities. This aspect of the study will be executed in two parts. In the first part, the committees will simulate the radiation exposure to ISS during the coming solar maximum (1998-2002) by shifting the radiation events of the last solar cycle (cycle 22) ahead one cycle. This simulation is justified since the consensus prediction for solar cycle 23 (during which ISS will be constructed) is that it will be very similar to solar cycle 22 (for which there are data on radiation intensities from solar storms). The radiation events will be superimposed on the Space Shuttle flight and EVA (extravehicular activities) schedule for ISS assembly. For the second part of the study, the committees will estimate how often "significant" disruption to activities might occur. This first-order estimate will not be based on a detailed analysis of the radiation dose to an astronaut. Instead, the committees will first establish thresholds (based on intensity and duration) which, if exceeded, would be expected to disrupt the mission schedule. Then they will examine solar events from cycle 22 to determine how often this threshold was exceeded during scheduled EVAs. This exercise will be repeated several times with different start times for the assembly flights to obtain statistics with which to express the impact assessment.

Examine existing arrangements within NASA to manage the radiation risk problem. This fact-finding part of the study would provide background information on ongoing and planned activities at NASA centers and at headquarters. It would also examine arrangements between the NASA science and life sciences codes.

Recommend how operational radiation support to ISS might be optimally accomplished. This part of the study would focus on current capabilities and planned roles and responsibilities in NASA, NOAA, and DOD for generating, disseminating, and using operational space weather products, and it would identify gaps or overlaps and opportunities for improving support.

Meetings: The Committee on Solar and Space Physics, working in conjunction with its federated partner, the Committee on Solar-Terrestrial Research, will take the lead in this study. The committees have considerable expertise related to space weather and its potential effects on Space Station. The study is planned as a 1-year effort with three 3-day meetings for further fact finding, discussions, and drafting the report. The first meeting will be held on June 29-July 1, 1998. Subsequent meetings would be held in the fall of 1998 and late January/early February 1999. The final meeting to complete the report would likely be held at the Beckman Center. Publication of the report would occur by July 1, 1999.



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