The Absolute Spectra of Galactic Cosmic Rays at Solar Minimum and Their Implications for Manned Spaceflight

Abstract

The radiation dose from galactic cosmic rays during a proposed mission to Mars is near the annual dose limit for the crew. Since the absolute spectra of galactic cosmic rays critically influences mission planning and spacecraft design, these spectra must be determined as accurately as possible. We have fit published measurements with solutions of the spherically symmetric diffusion equation to make accurate representations of the spectra. We report preliminary determinations on the absolute differential energy spectra at 1 AU and discuss the implications for the proposed missions to Mars.