Atmospheric Sciencefor & with InSight

Aymeric Spiga, François Forget,
Ehouarn Millour, Tanguy Bertrand
Laboratoire de Météorologie Dynamique,Paris, FranceDon Banfield
Cornell UniversityLMD

InSight Science Goal:
Understand the formationand evolution of terrestrial
planets through investigation of the interior structure
and processes of Mars.
 Seismology

 Geodesy Heat Flow Magnetism
Courtesy of B. Banerdt & S. Smrekar
1How Does a Terrestrial Planet Form?
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1. The planet starts forming throughaccretion of meteoritic material.
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2. As it grows, the interior begins to heat upand melt.
happens!
3. Stuff happens…

InSight!

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4. The planet ends up with a crust, mantle,
and core with distinct, non-meteoritic
compositions.
Courtesy of B. Banerdt

2InSight Payload
Wind and Thermal
Shield (WTS)

RISE (S/C Telecom)

SEIS (CNES)(also IPGP, ETH/SSA, MPS/DLR,IC/Oxford/UKSA, JPL/NASA)

Seismic Experiment for Interior Structure

Rotation and Interior
Structure Experiment
Small Deep SpaceTransponder

Thermal Enclosure(RWEB)

HP3 (DLR)Heat Flow and Physical Properties Probe
Radiometer

Support
Structure

Electronics (Ebox)Back End
Electronics

TetherLengthMonitor

Sensor Head:VBB, SP, LVL

Tether (THR)

IDS (JPL)
Instrument Deployment System

IFG (UCLA) – InSight
FluxGate

Scientific Tether• Embedded T sensors for thermal
gradient measurements
Pressure SensorMole• Hammering mechanism• Active thermal conductivity
measurements• Static Tilt sensors

TWINS (CAB) – Temp.
and Wind for INSight

IDA – Instrument Deployment Arm

APSS (JPL)IDC – Instrument Deployment Camera

Auxiliary PayloadSensor Suite

ICC – Instrument Context Camera

Courtesy of B. Banerdt & S. Smrekar

Martian Seismology – Multiple Signal Sources
Rate of Seismic Activity
3Magnitude
456Faulting
ExpectedRange

Atmospheric
Excitation

Body
Waves
SurfaceWaves

Phobos Tide
Normal Modes

Courtesy of B. Banerdt

InSight
Landing Area

Meteorite Impacts

Daubar et al., 201014 January, 2015

InSight Flight School – Arcadia, CA

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Atmospheric Science expertise and tools …
• … for InSight– Predict environmental conditions to prepare EDL and operations– Characterize and minimize seismic noise from the atmosphere• … with InSight
Prepare P,T,winds,tau measurement strategy and interpretation– Dust cycle– Water cycle– Atmospheric perturbations

15 January 2015

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Tools @ LMD to study the atmospheric environment

Mars Climate Database:www-mars.lmd.jussieu.fr
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Atmospheric Science expertise and tools …
• … for InSight– Predict environmental conditions to prepare EDL and operations– Characterize and minimize seismic noise from the atmosphere• … with InSight
Prepare P,T,winds,tau measurement strategy and interpretation– Dust cycle– Water cycle– Atmospheric perturbations

15 January 20157

Large-scale winds on Mars @ InSight landing site
MCD v5.0 dust storm average solar scenario Ls=226° - Altitude 10mLocal time at Insight Landing site: 14:00

Large-scale winds on Mars @ InSight landing site
Above the surface ~5m - Simulated with the LMD-GCM over one martian year
WestLs ~300°
science mission
Higher amplitude
Higher variability
Ls ~230°landingMesoscale wind study @ InSight landing ellipses• We focus on what simulations yield for near surface winds at
the 4 Insight landing ellipses (E05, E08, E09, E17).
• 6 Simulations, using realistic dust scenarios, spread overvarious Ls (30,90, 226, 293) and Mars Years (MY24, 25, 28).

Regional winds : sensitivity to season and dust opacity
Ls = 226° tau=0.2

Change : Ls = 293°

Change : tau=1

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Atmospheric Science expertise and tools …
• … for InSight– Predict environmental conditions to prepare EDL and operations– Characterize and minimize seismic noise from the atmosphere• … with InSight
Prepare P,T,winds,tau measurement strategy and interpretation– Dust cycle– Water cycle– Atmospheric perturbations

15 January 2015

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Atmospheric excitation of the surface
Modelling boundary layer seismic noise with Large-Eddy Simulations

Simplified pressure noise model: methodology• For every section of the LES grid, the variation of the vertical force exerted on the groundat the center of the section of the grid is calculated.
• Then, the displacement of the ground at the seismometer feet will be a sum of thedisplacements caused by each section of the grid (each considered to be a point source).
• Once the vertical displacement at each of the seismometers feet has been calculated,
the resulting acceleration tilt can be found.
ΔF = ΔP.A• The size of each section ofthe LES grid is 50 m x 50 m.

Courtesy of N. Murdoch

Dustdevils on the Vertical Component (3/3)

Courtesy of P. Lognonné

Atmospheric Science expertise and tools …
• … for InSight– Predict environmental conditions to prepare EDL and operations– Characterize and minimize seismic noise from the atmosphere• … with InSight
Prepare P,T,winds,tau measurement strategy and interpretation– Dust cycle– Water cycle– Atmospheric perturbations

15 January 2015

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Atmospheric science with InSight• Insight offers opportunities to improve our knowledge of theMartian atmospheric system:- Long term high accuracy measurements of winds,
temperature, pressure- Dust devil detection and monitoring, but also
convective activity evaluation using high freq.
pressure measurements- Dust opacity measurements (using camera andeffective dust deposition on solar panels)- Water ice cloud and near-surface fog cycles(seasonal and diurnal) studies- …

Pressure : THE meteorological variable• Interannual & Seasonal variations– CO2 condensation cycle• Day-to-day variations– passing weather patterns (equator)• Diurnal variations– thermal tides• Hour-to-hour variations– gravity waves, slope winds• Minutes-to-minutes variations– boundary layer convection, gravity waves• Second-to-second variations– convective vortices (dust devils)
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Seasonal and Secular Pressure Record• Monitor seasonal pressure changes• High accuracy/stability desired to constrain secular pressuretrends– Residual Polar Cap losing mass? (Malin et al. ‘01)
– Accurate pressure measurements can detect this (Haberleand Kahre, ‘10)– Pressure stability TBD

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Thermal tides : typical vs. dust storm conditions

Daily cycleof surfacepressure

16 January 201420

Gravity waves  observed on pressure ?
Terrestrial measurements
Gossard & Munk Journal of Meteorology 1954

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Surface pressure variations : convective cells

22Turbulent horizontal winds

23Surface pressure variations : convective vortices
Curiosity REMS Observations (October 2012)

Observed
Dust devil
like vortices
NASA/JPL-Caltech/ CAB(CSIC-INTA)

Surface pressure variations : convective vortices

ModeledDust devil
like vortices25

Atmospheric science with cameras• Clouds : diurnal and seasonal evolution• Dust opacity: seasonal evolution
and storm monitoring• Aeolian processes: witness lifting events (and assess wind
threshold for motions?), seasonal evolution of ripple migration

Seasonal cycle of water ice clouds and fogs

TES (daytime IR observations) water ice cloudoptical depth database (Smith 2008)••MARCI (daytime UV observations) extracted
from SSI MARCI cloud optical depth
database (Wolff et al. 2013)
GCM prediction of water ice
fog near the surface
Fog present only at distincttimes of year

Diurnal cycle of water ice clouds and fogs
Thicker clouds develop during the night

Near surface fog develops during thenight and vanishes at daybreak.

Summary and Conclusions• InSight: equatorial lander with meteorological package + highresolution pressure sensor + cameras• Increment existing datasets : wind, T, dust opacity, clouds• Pressure– Increment existing large-scale diagnostics– New science for boundary layer and gravity waves• LMD atmospheric models: GCM, mesoscale, LES– Involved for preparation & analysis– Happy to help with atmospheric expertise29