PICAM sur Mars Express: (putain,)10 ans !

F. Montmessin et l’équipe SPICAM au LATMOS France: LATMOS, LMD, IASRussia: IKIBelgium: IASB, Univ. LiègeU.S.: SwRI, Univ. of Arizona

L’équipe SPICAM• France (LATMOS, LMD, IAS):

F. Montmessin (PI), J.-L. Bertaux (ex-PI), A. Reberac, G. Lacombe, N. Chapron, F. Lefèvre, J.-Y. Chaufray, F. Leblanc, F. Forget, S. Lebonnois, E. Quémerais, L. Maltagliati, A. Määttänen, C. Listowski, B. Gondet

• Russie (IKI) : O. Korablev (CoPI), A. Fedorova, A. Trokhimovsky, A.V. Rodin

• Belgique (IASB, Univ. de Liège) : A.-C. Vandaele, N. Mateshvili, Y. Willamme, J.-C. Gérard, A. Stiepen, D. Fussen, C. Simon

• U.S. (LPL): B. Sandel, A. Stern

• Collaborations: P. Withers, S. Bougher, T. McDunn, N. Schneider, etc.

SPICAM on Mars 96: 40 kg

SPICAM « light » on Mars Express:4.8 kg

UV Grating Imaging

Spectrometer (4 kg)

IR AOTF Spectromete

r (0.8 kg) SPICAM IR solar (23 kg)

SPICAM UV/Vis étoile (17 kg)

Schéma Optique

Nadirdirection

M

Ø30

Light trap

Telescope

FOV diaphragm

AOTF

IR detectors

Sundirection

Nadirdirection

40x40

Parabolicmirror Slit

Grating

Intensifier

CCD

M

FibreUV

IR

Bertaux et al. (JGR,2006)

Instrument développé au LATMOS (ex-Service d’aéronomie).

Le même instrument vole sur la mission ESA Venus Express.

Bande spectrale / Résolution:UV: 118-320 nm R=150 IR: 1.0-1.7 µm

R=1300

Modes d’observation : • Occultation (étoile /

soleil)• Nadir• Limbe

UV Spectrometer -3

kg-

IR Spectrometer -

800 g-

Light IN OUT

RF IN

TeO2 crystal

Transducer

Mars Express spacecraft

orbit

MARS

NADIR : l’instrument vise dans la direction du centre de la planète = mesure du spectre de la lumière solaire réfléchie par la surface et l’atmosphère Colonne d’abondance des

constituants CO2, O3, H2O responsables des absorptions observées

Mars Express spacecraft

orbit

MARS

LIMBE : L’instrument vise le “bord”de la planète = mesure du spectre des émissions et diffusion du spectre solaire par l’atmosphère Profil vertical en altitude des émissions aéronomiques et des poussières

Spectrum of the star :

outside the atmosphere

through the atmosphere

star

Mars Express spacecraft

orbit

MARS

Line of sight

OCCULTATION : L’instrument vise une étoile à travers l’atmosphère de la planète = mesure du spectre de l’étoile à travers et hors atmosphère profils verticaux des constituants responsables des absorptions observées (CO2, O3, O2, CO, H2O, aérosols)

NO δ C2 – X2

NO γ A2 + – X2

H Lyα

Spectre UV (côté nuit)

Bertaux et al. (Science, 2005)

O21Dg

The oxygen O21Dg emission line

at 1.27 mm is produced by UV dissociation of O3

H2O ice

CO2 ice

Korablev et al. (JGR, 2006)

Etat des lieux• Instrument health:

• UV channel defects noticed since orbit #2639 = additional “cleaning” stage in the pipeline

• Further degradation since Safe Mode #25 of Mars Express in summer 2011

• IR channel has operated flawlessly and continues to do so• Data Production:

• MEx has completed its 10,000th orbit in 2011• SPICAM has achieved >10,000 observations and collected

13,500,000 UV spectra and 2,000,000 IR spectra to date • 63 Giga-Octets of data transmitted to Earth

• Science Production:• 60 publications • JGR special edition (SPICAM results) in 2006• >180 communications in workshops/conferences

Thèmes scientifiques couverts

1. Emissions spontanées de l’atmosphère:• NO detection and characterization (UV )• Auroras and Dayglows (CO2

+, CO, etc.) (UV) • Hydrogen and Oxygen corona (UV)• O2 dayglow/nightglow (IR) (also relevant to 2.)

2. Composition et climat:• Ozone, carbon dioxide (temperature) and water vapor mapping

and vertical profiling (UV & IR) • Aerosols and clouds characterization (UV & IR)

3. Surface(s) :• Phobos and Deimos observations (UV)

Quelques accomplissements SPICAMesques…..

1. Martian Airglows:• First detection of Nitric Oxide emissions, revealing atmospheric global

circulation pattern;• First detection of auroras above crustal magnetic field anomalies;• Characterization of dayglow and nightglow emissions;• Characterization of the O and H Martian corona.

2. Atmospheric Composition & Climate• Detection of mesospheric (>100 km) cloud layers, of likely CO2

ice origin;• First annual mapping of O3, simultaneously with H2O;• 4D (x,y,z,t) distribution of O3 and H2O through combination of

occultation and nadir modes;• Compilation of the largest density/temperature dataset in the

mesospheric/thermospheric 70 to 140 km altitude range;• Detection of water vapor in a high supersaturation state.

Spectrum of the star :

outside the atmosphere

through the atmosphere ratio

star

Atmospheric Transmission

Mars Express spacecraft

orbit

SPICAM Ultra-Violet

observations, orbit #17

13 jan. 2004

MARS

Line of sight

Occultation sequence

1 spectrum / second Dz~1-3 km

Prominent signatures of CO2, O3 and

aerosols

CO2 profile gives T(z)

Aerosols affect wholespectral range and

exhibits a pronounced spectral slope

Forget et al. (JGR, 2009)

• Large differences between SPICAM observations and LMD GCM predictions for the mesopause altitude and temperature

• O underestimated by model = CO2 cooling underestimated

Nuages mésosphériques martiens

Montmessin et al. (Icarus, 2006)

Simultaneous temperature

profile inversion indicates that layers appear partly inside

supersaturated pockets of CO2

Nuages mésosphériques martiens : de la glace de CO2 ?

Määttänen et al., Icarus, 2013

Evolution spatio-temporelle de l’activité nuages/aérosols :

• Occultations stellaires/solaires confondues

• Suivi de la hauteur max (plafond) des aérosols correspondant à une opacité colonne le long de la ligne de visée de 1

Ztop

Mars Express spacecraft

orbit

MARS

NADIR : l’instrument vise dans la direction du centre de la planète = mesure du spectre de la lumière solaire réfléchie par la surface de la planète après qu’elle est traversée l’atmosphère

comparaison spectre mesuré/spectre solaire : Colonne d’abondance des constituants CO2, O3, H2O responsables des absorptions observées

1.4

1.2

1.0

0.8

0.6

0.4

0.2

0.0

Rel

ativ

e al

bedo

320300280260240220200 wavelength (nm)

SPICAM relative albedo model with Earth O3/200 model with Earth O3

Observation nadir : principe

θ1

Scattering by surface with albedo A

MEX/ SPICAM

tv vertical optical thickness of absorption, varies strongly with wavelength

Absorptionby gas CO2

Water vapour band

SPICAM – near Infrared observations, orbit 8, 9 jan. 2004

SPICAM – Ultra-Violet observations, orbit 8, 9 jan. 2004

UV

IR

Perrier et al. (J. Geophys. Res., 2006)

Lefèvre et al. (2013)

MY29

MY27

MY28

Multi-annual monitoring of H2O water vapor

MY30

MY27

MY28

H2O, pr.mm

Ls

Annual water vapor cycle: an average view

All years combined

1 km3

of ice

H2O pr.mm

MY29

MY27

Interannual variability of H2O vapor

MY30

MY28

H2O, pr.mm

sun

Atmospheric Transmission

Mars Express spacecraft

orbitSPICAM Infrared

observations

Line of sight

SPICAM data LMD GCM predictions

north

south

northern spring-summerMaltagliati et al. (Science,

2011)

Maltagliati et al. (Science, 2011)

Credit: ESA/AOES Medialab

north

south

southern spring

SPICAM data LMD GCM predictions

Maltagliati et al. (Icarus, 2013)

Meeting SPICAM/SPICAVPoros Island (Greece): 28 june to 2 july 2010

50 – 100 ppm of water vapor at 60 km, for ~5 Ls

60 km

Climate Model results:Water vapor contours (colors) superimposed on circulation pattern

Montmessin et al., 2004

0.1 50 200ppm

Northern summer Southern summer

Aphelion cloud belt formation

at z ~15 km

On an annual average, the climatic asymmetry favors accumulation/storage of water in the north.

60 km

Montmessin et al., 2004

0.1 50 200ppm

Aphelion cloud belt formation

at z ~15 km

Southern summerNorthern summer

60 km

Montmessin et al., 2004

0.1 50 200ppm

Southern summerNorthern summer

SPICAMGCM

MY29

MY27

MY30

MY28

H2O, pr.mmInterannual variability of H2O vapor

MY29

MY27

MY30

MY28

H2O, pr.mmInterannual variability of H2O vapor