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Dr. John F. Cooper
Heliospheric Physics Laboratory
NASA Goddard Space Flight Center, Greenbelt, MD

September 28th, 2016, 12:00PM,  
Thirkield Hall (Physics), room 103

 
Virtual Energetic Particle Observatory: Radiation Environment at Mars and its Moons  [PDF]

ABSTRACT:  Planning of robotic and human exploration of Mars and its two
moons, Phobos and Deimos, requires understanding of the local radiation
environment at the orbit of Mars and how these moons are affected by that
radiation in proximity to Mars. The NASA Virtual Energetic Particle Observatory
(VEPO) at vepo.gsfc.nasa.gov provides enhanced on-line access to hot plasma
and energetic particle data from ongoing and legacy spacecraft missions that
can be used to assess the radiation environment of the inner solar system from
Mercury to Mars. The Pioneer 10-11, Voyager 1-2, Ulysses, and various
planetary spacecraft crossed the orbit of Mars at various times over several
solar cycles, while continuous measurements were being made by a series of
spacecraft near Earth or its 1-AU orbit around the Sun. VEPO is used to
investigate whether long-term averages of energetic particle flux spectra have
significant variation in the inner solar system from comparison of data from the
various spacecraft. The local radiation environment at the innermost moon,
Phobos, is discussed in terms of the VEPO data study and the natural radiation
shielding characteristics of the Mars-Phobos system. The sub-Mars point on the
Phobos surface would be a high-value location for remote monitoring and
coordination of exploration activities on the surface of Mars. Elsewhere on
Phobus, the irregular shape of the moon produces significant variance in
radiation intensities that can be accounted for in planning of mobile exploration
of Phobus.