NASA Logo

NTRS

NTRS - NASA Technical Reports Server

Collections About News Help Login
Back to Results
Space Radiation Risk Assessment for Future Lunar MissionsFor lunar exploration mission design, radiation risk assessments require the understanding of future space radiation environments in support of resource management decisions, operational planning, and a go/no-go decision. The future GCR flux was estimated as a function of interplanetary deceleration potential, which was coupled with the estimated neutron monitor rate from the Climax monitor using a statistical model. A probability distribution function for solar particle event (SPE) occurrence was formed from proton fluence measurements of SPEs occurred during the past 5 solar cycles (19-23). Large proton SPEs identified from impulsive nitrate enhancements in polar ice for which the fluences are greater than 2 10(exp 9) protons/sq cm for energies greater than 30 MeV, were also combined to extend the probability calculation for high level of proton fluences. The probability with which any given proton fluence level of a SPE will be exceeded during a space mission of defined duration was then calculated. Analytic energy spectra of SPEs at different ranks of the integral fluences were constructed over broad energy ranges extending out to GeV, and representative exposure levels were analyzed at those fluences. For the development of an integrated strategy for radiation protection on lunar exploration missions, effective doses at various points inside a spacecraft were calculated with detailed geometry models representing proposed transfer vehicle and habitat concepts. Preliminary radiation risk assessments from SPE and GCR were compared for various configuration concepts of radiation shelter in exploratory-class spacecrafts.
Document ID
20070016627
Acquisition Source
Johnson Space Center
Document Type
Conference Paper
Authors
Kim, Myung-Hee Y. (NASA Johnson Space Center Houston, TX, United States)
Ponomarev, Artem (NASA Johnson Space Center Houston, TX, United States)
Atwell, Bill (Boeing Co. Houston, TX, United States)
Cucinotta, Francis A. (NASA Johnson Space Center Houston, TX, United States)
Date Acquired
August 23, 2013
Publication Date
July 12, 2007
Subject Category
Space Radiation
Meeting Information
Meeting: International Congress of Space Radiation Research
Location: San Francisco, CA
Country: United States
Start Date: July 8, 2007
End Date: July 12, 2007
Distribution Limits
Public
Copyright
Public Use Permitted.

Related Records

There are no records associated with this record.
No Preview Available