Publications (25)
The nitrogen cycles on Pluto over seasonal and astronomical timescales
T. Bertrand, F. Forget, O. M. Umurhan +13
Pluto's landscape is shaped by the cycles of the volatile ices covering its surface. In particular, the Sputnik Planitia (SP) ice sheet displays a large diversity of terrains, with…
Thermal structure and aerosols in Mars' atmosphere from TIRVIM/ACS onboard the ExoMars Trace Gas Orbiter : validation of the retrieval algorithm
Sandrine Guerlet, N. Ignatiev, F. Forget +12
The Atmospheric Chemistry Suite (ACS) onboard the ExoMars Trace Gas Orbiter (TGO) monitors the Martian atmosphere through different spectral intervals in the infrared light. We pre…
High-Order harmonics of Thermal Tides observed in the atmosphere of Mars by the Pressure Sensor on the Insight lander
J. Hernandez-Bernal, A. Spiga, F. Forget +1
Thermal tides are atmospheric planetary-scale waves with periods that are harmonics of the solar day. In the Martian atmosphere thermal tides are known to be especially significant…
Volatile transport modeling on Triton with new observational constraints
T. Bertrand, E. Lellouch, B. J. Holler +18
Neptune's moon Triton shares many similarities with Pluto, including volatile cycles of N2, CH4 and CO, and represents a benchmark case for the study of surface-atmosphere interact…
Observations of Water Frost on Mars with THEMIS: Application to the Presence of Brines and the Stability of (Sub)Surface Water Ice
L. Lange, S. Piqueux, C. S. Edwards +4
Characterizing the exchange of water between the Martian atmosphere and the (sub)surface is a major challenge for understanding the mechanisms that regulate the water cycle. Here w…
Eight-year Climatology of Dust Optical Depth on Mars
L. Montabone, F. Forget, E. Millour +8
We have produced a multiannual climatology of airborne dust from Martian year 24 to 31 using multiple datasets of retrieved or estimated column optical depths. The datasets are bas…
3D Modelling of the climatic impact of outflow channel formation events on Early Mars
M. Turbet, F. Forget, J. W. Head +1
Mars was characterized by cataclysmic groundwater-sourced surface flooding that formed large outflow channels and that may have altered the climate for extensive periods during the…
InSight Pressure Data Recalibration, and Its Application to the Study of Long-Term Pressure Changes on Mars
L. Lange, F. Forget, D. Banfield +9
Observations of the South Polar Residual Cap suggest a possible erosion of the cap, leading to an increase of the global mass of the atmosphere. We test this assumption by making t…
The Martian mid-latitude subsurface ice is the remnant of a past ice sheet
E. Vos, F. Forget, L. Lange +3
On Mars, a relatively pure water ice layer lies beneath several centimeters of dry soil at mid-latitudes. Its widespread presence poleward of 60° latitude was detected by remote n…
Pluto's lower atmosphere and pressure evolution from ground-based stellar occultations, 1988-2016
E. Meza, B. Sicardy, M. Assafin +167
Context. Pluto's tenuous nitrogen (N2) atmosphere undergoes strong seasonal effects due to high obliquity and orbital eccentricity, and has been recently (July 2015) observed by th…
No detection of SO2, H2S, or OCS in the atmosphere of Mars from the first two Martian years of observations from TGO/ACS
Ashwin S. Braude, F. Montmessin, K. S. Olsen +13
The detection of sulphur species in the Martian atmosphere would be a strong indicator of volcanic outgassing from the surface of Mars. We wish to establish the presence of SO2, H2…
Global seasonal variations of the near-surface relative humidity levels on present-day Mars
B. Pál, Ã. Kereszturi, F. Forget +1
We investigate the global seasonal variations of near-surface relative humidity and relevant attributes, like temperature and water vapor volume mixing ratio on Mars using calculat…
Modelling Slope Microclimates in the Mars Planetary Climate Model
L. Lange, F. Forget, E. Dupont +5
A large number of surface features (e.g., frost, gullies, slope streaks, recurring slope lineae) are observed on Martian slopes. Their activity is often associated with the specifi…
Constraints on the structure and seasonal variations of Triton's atmosphere from the 5 October 2017 stellar occultation and previous observations
J. Marques Oliveira, B. Sicardy, A. R. Gomes-Júnior +234
A stellar occultation by Neptune's main satellite, Triton, was observed on 5 October 2017 from Europe, North Africa, and the USA. We derived 90 light curves from this event, 42 of…
Pluto's Haze as a Surface Material
W. M. Grundy, T. Bertrand, R. P. Binzel +37
Pluto's atmospheric haze settles out rapidly compared with geological timescales. It needs to be accounted for as a surface material, distinct from Pluto's icy bedrock and from the…
Is Gliese 581d habitable? Some constraints from radiative-convective climate modeling
R. Wordsworth, F. Forget, F. Selsis +3
The recently discovered exoplanet Gl581d is extremely close to the outer edge of its system's habitable zone, which has led to much speculation on its possible climate. We have per…
Study of gravity waves distribution and propagation in the thermosphere of Mars based on MGS, ODY, MRO and MAVEN density measurements
M. Vals, A. Spiga, F. Forget +3
By measuring the regular oscillations of the density of CO in the upper atmosphere (between 120 and 190~km), the mass spectrometer MAVEN/NGIMS (Atmosphere and Volatile Evolut…
EChO - Exoplanet Characterisation Observatory
G. Tinetti, J. P. Beaulieu, T. Henning +131
A dedicated mission to investigate exoplanetary atmospheres represents a major milestone in our quest to understand our place in the universe by placing our Solar System in context…
Impact of gravity waves on the middle atmosphere of Mars: a non-orographic gravity wave parameterization based on Global Climate modeling and MCS observations
G. Gilli, F. Forget, A. Spiga +7
The impact of gravity waves (GW) on diurnal tides and the global circulation in the middle/upper atmosphere of Mars is investigated using a General Circulation Model (GCM). We have…
Global modelling of the early Martian climate under a denser CO2 atmosphere: Water cycle and ice evolution
R. Wordsworth, F. Forget, E. Millour +3
We discuss 3D global simulations of the early Martian climate that we have performed assuming a faint young Sun and denser CO2 atmosphere. We include a self-consistent representati…
A Reappraisal of Subtropical Subsurface Water Ice Stability on Mars
L. Lange, F. Forget, M. Vincendon +6
Two arguments have suggested the presence of subsurface water ice at latitudes lower than 30\textdegree~on Mars. First, the absence of CO2 frost on pole-facing slopes was explained…
Wind measurements in Mars' middle atmosphere at equinox and solstice: IRAM Plateau de Bure interferometric CO observations
R. Moreno, E. Lellouch, T. Encrenaz +4
Characterizing the Martian atmosphere is an essential objective to understand its meteorology and its climate. The lower atmosphere (< 40 km) and middle atmosphere (40-80 km) of Ma…
The CH4 cycles on Pluto over seasonal and astronomical timescales
T. Bertrand, F. Forget, O. M. Umurhan +13
New Horizons observations suggest that CH4 on Pluto has a complex history, involving reservoirs of different composition, thickness and stability controlled by volatile processes o…
Exploring the spatial, temporal, and vertical distribution of methane in Pluto's atmosphere
E. Lellouch, C. de Bergh, B. Sicardy +3
High-resolution spectra of Pluto in the 1.66 um region, recorded with the VLT/CRIRES instrument in 2008 (2 spectra) and 2012 (5 spectra), are analyzed to constrain the spatial and…
Stratigraphic and Isotopic Evolution of the Martian Polar Caps from Paleo-Climate Models
E. Vos, O. Aharonson, N. Schorghofer +4
Exposed scarps images and ice-penetrating radar measurements in the North Polar Layered Deposits (NPLD) of Mars show alternating layers that provide an archive of past climate osci…