Mars - orbit & surface
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GCRs + secondaries:
what we know:
- primaries ~ flux like that of interplanetary spectrum
- secondaries --> model only: SIREST (w/ HZTERN, FLUKA, etc)
-ISS experiments to validate transport codes, HEND on Odyssey (HZETRN, FLUKA, HETC, MCNPX)
what we need:
-validation of orbit and surface rad env models ("be there before you go")
-dust effects on transport????
how we get there:
- code validation needed (e.g. on stratospheric balloon Deep Space Testbed [DSTB])
(get comments from Townsend committee)
- need Mars surface level measurements including
surface neutrons for code tests and validation (note an atmosphere
model is part of the transport model-atmosphere is variable-)
endorse MSL RAD measurements also other exp? on MSL (is this enough for transport model valid?)
splinter group of space environment and transport code types to look at the above and
assess other needs/studies that need to be done
SEPs: what we know:
-primaries expected to be different from Earth observations due to heliospheric nonuniformity
of SEP events and modest radial attenuation - but few real comparative measurements other than
MARIE (on Odyssey) measurements and Phobos (questiob as to how well knowledge of SEP events
at Earth answers most important questions about SEPs at Mars)
-secondaries issues the same as GCRs- model only
-Mars causes SEP shadows in orbit (but not understood)m and any other Mars effects
how we get there:
- test softer spectral range performance of codes, including SEP heavy ions
treatment & crustal fields effects
- require interplanetary input measurements to make MSL meas useful
endorse MSL RAD (but no upstream SEP input measurements currently planned)
Upper atmosphere/ionosphere effects:
what do we know:
- Atmos/ionos. highly variable (e.g. dust storms, dynamics, solar X-ray + EUV variations,
auroras and likely SEP-related ionization, heating, solar wind interaction-related, etc)
- atmos. models exist (e.g. including "official" models used to design missions..e.g. COSPAR
models) but poorly validated. Include an Upper atmosphere TGCM, exosphere two-stream
and Monte Carlo, lower atmosphere GCMs.
-ionosphere models exist but not dynamic. One 3D model includes crustal fields (U of Mich.)
- atmos/ionosphere existing measurements
in-situ Viking (2 profiles on landers)
radio occultation profiles from Mariner, Viking, MGS?
drag measurements on several missions including recent
near-surface atmos. on landers +imaging of wind activity, dust devils, etc.
MGS upper ionosphere in-situ (shows crustal field and other effects)
existence of small-scale irregularities (neutral atmos and ionos) suggested by observations
- limited in-situ atmos./ionos observations. Remote sensing results?? (need update)
- limited supporting airglow, solar wind, EUV measurements from Phobos, MGS,
Mars Express. Local rad. env. measurements on Mars Odyssey (MARIE) only,
so difficult to evaluate cause/effect of the related variations
what we need:
- need well validated models for orbiting, aerobraking, landing (to the ground)
- determine if scintillation or ionosphere/atmosphere disturbances from dust storms
or space weather are a factor and where (altitudes, geog. locations)
- determine how solar/interplanetary variations affect the upper atmosphere/ionosphere
and near-surface conditions and equipment/technologies
how do we get there:
- Collect and synthesize lessons learned from aerobraking, drag experiments at Mars
and communications at Mars including rover to orbiter, plus "real" atmos. measurements
from radio occultations, available in-situ measurements and remote sensing (nneds a special
Program and AO for that end??)
-validate and further develop (e.g for variability, extremes) atmosphere models using
Mars "aeronomy" and main atmosphere missions and/or measurements, lander descent profiles
and weather stations, landed networks of met stations, balloons, to address shortcomings
(need to coordinate with Mars Exploration Program or design own missions to address))
- Develop solar wind interaction models coupled w/upper atmosphere & ionosphere models
- Make landed, balloon, rover measurements of mag. and electric fields (incl. d/dt measurements),
radio signal absorption and noise (riometer), conductivity, EUV, dust electrification/adhesion,
properties
-coordination with Mars Exploration Program
OTHER:
-concerns over synthesizing committee reports/study conclusions (e.g. LWS, MEPAG, SSE Roadmap, Mars Exploration
Program, Mars Human Precursor Study, NRC commitees, COSPAR European Mars Climate Data Base Comm,, EXOMARS
mission study (ESA), Solar and Space Phys Roadmap, Astrobiology links? others)-some conclusions, priorities may
conflict