The Venus Emissivity Mapper Concept

Based on experience gained from using the VIRTIS instrument on Venus Express to observe the surface of Venus and the new high temperature laboratory experiments, we have developed the multispectral Venus Emissivity Mapper (VEM) to study the surface of Venus. VEM imposes minimal requirements on the spacecraft and mission design and can therefore be added to any future Venus mission. Ideally, the VEM instrument will be combined with a high-resolution radar mapper to provide accurate topographic information, as it will be the case for the NASA Discovery VERITAS mission or the ESA EnVision M5 proposal

Mars – Ion and Neutral Energy Analyser: A new instrumental concept to characterize Mars’ upper atmosphere

International audienceThe “Mars Magnetosphere ATmosphere Ionosphere and Space-weather SciencE (M-MATISSE)” mission is an ESA Medium class (M7) candidate currently in Phase-A study by ESA. M-MATISSE main scientific goal is to unravel the complex and dynamic couplings of the magnetosphere, ionosphere and thermosphere (MIT coupling) with relation to the Solar Wind (i.e. space weather) and the lower atmosphere of Mars. Among the set of instruments present onboard the platform, the Mars – Ion and Neutral Energy Analyzer (M – INEA) is an energy spectrograph and mass spectrometer specifically designed to image the low energy range of the neutral particles’ energy distribution (<10eV) with a high energy resolution (~0.1 eV).The innovative concept of this instrument consists in the use of an energy analyser capable ofinstantaneously imaging the energy spectrum of the particles entering the instrument. In addition, atime-of-flight mass analysis is also performed, allowing the mass to be determined simultaneouslywith its energy. Thanks to an End-to-End model developed with the software SIMION, theperformances of the instrument were estimated. The model predicts a resolution in mass of ~22 andin energy better than 0.1 eV as well as a resolution in temperature and velocity better than 50K and20 m/s respectively. With such capability, M-INEA could, for the first time, provide directmeasurement of Mars’ neutral atmospheric escape rate and ultimately bring crucial information tounderstand the history of the Red Planet Atmosphere. Additionally, with the ability toinstantaneously image the energy distribution along the ram direction of the spacecraft, theinstrument is also able to measure the temperature and the drift velocity of the particles in theMartian upper atmosphere. At the same time, we have been working on the development of an ion source, also necessary forthe optimal operation of M-INEA, and based on the use of carbon nanotubes (CNT) as electronemitters instead of usual hot filaments. The measured efficiency of this source is comparable to thatof sources using hot filaments in mass spectrometers flown on recent space missions, such asROSINA on Rosetta or NGIMS on MAVEN. Cold emission by CNTs requires much less electrical powerthan hot filaments and prevents the detrimental instrumental effects due to the outgassing of theheated walls of the ion source and the space charge in high intensity electron beams. The longevityand stability of CNT cathodes are also demonstrated with a test including ∼700 h of continuousemission, showing only a drop of about 20% of the emitted (Steichen et al., 2024).At present day, the first prototype of M-INEA has been assembled and is being tested atinstrumental level. The results obtained during the test campaign will confirm the instrumental concept of M-INEA and give a first estimation of the real performances of the instrumen

The Venus InfraRed Atmospheric gases Linker instrument concept on-board the Venus Orbiter Mission of the Indian Space Research Organization

International audienceIn 2019, the Indian Space Research Organisation (ISRO) opened an Announcement of Opportunity to the international science community to study Venus for space-based experiments onboard planned ISRO's Venus Orbiter Mission. The joint proposal of Space Research Institute (Russia) and Laboratoire Atmosphères, Observations Spatiales, UVSQ Université Paris-Saclay (France) was chosen by the ISRO mission program committee. The VIRAL (Venus InfraRed Atmospheric gases Linker) project is aimed at proposing a remote sensing infrared (IR) spectrometer to provide first-class information on the composition and structure of the atmosphere at the top and above the cloud layer of Venus. VIRAL leverages from the legacy of a generation of spectrometers that has achieved very high detecting performances in a compact, light-weight, and easily-to-design. VIRAL will cover the IR range from 2.3 to 4.3 μm that will allow the retrieval of the layering of the Venusian upper atmosphere and its composition. The list of measured species includes CO2 and its main isotopes (with related retrievals of the atmospheric temperature), H2O and HDO (related to the evolution of water on Venus), CO, SO2, HCl, HF, H2SO4 droplets and aerosols. Its enhanced sensitivity will allow establishing refined upper limits or new detections for a number of trace gasses, such as OCS, H2S, H2CO, C2H2. An exclusive science goal is to trace phosphine, recently announced in Venus atmosphere. The concept, design and expected performance will be reported

The Venus InfraRed Atmospheric gases Linker instrument concept on-board the Venus Orbiter Mission of the Indian Space Research Organization

International audienceIn 2019, the Indian Space Research Organisation (ISRO) opened an Announcement of Opportunity to the international science community to study Venus for space-based experiments onboard planned ISRO's Venus Orbiter Mission. The joint proposal of Space Research Institute (Russia) and Laboratoire Atmosphères, Observations Spatiales, UVSQ Université Paris-Saclay (France) was chosen by the ISRO mission program committee. The VIRAL (Venus InfraRed Atmospheric gases Linker) project is aimed at proposing a remote sensing infrared (IR) spectrometer to provide first-class information on the composition and structure of the atmosphere at the top and above the cloud layer of Venus. VIRAL leverages from the legacy of a generation of spectrometers that has achieved very high detecting performances in a compact, light-weight, and easily-to-design. VIRAL will cover the IR range from 2.3 to 4.3 μm that will allow the retrieval of the layering of the Venusian upper atmosphere and its composition. The list of measured species includes CO2 and its main isotopes (with related retrievals of the atmospheric temperature), H2O and HDO (related to the evolution of water on Venus), CO, SO2, HCl, HF, H2SO4 droplets and aerosols. Its enhanced sensitivity will allow establishing refined upper limits or new detections for a number of trace gasses, such as OCS, H2S, H2CO, C2H2. An exclusive science goal is to trace phosphine, recently announced in Venus atmosphere. The concept, design and expected performance will be reported

The Venus InfraRed Atmospheric gases Linker instrument concept on-board the Venus Orbiter Mission of the Indian Space Research Organization

International audienceIn 2019, the Indian Space Research Organisation (ISRO) opened an Announcement of Opportunity to the international science community to study Venus for space-based experiments onboard planned ISRO's Venus Orbiter Mission. The joint proposal of Space Research Institute (Russia) and Laboratoire Atmosphères, Observations Spatiales, UVSQ Université Paris-Saclay (France) was chosen by the ISRO mission program committee. The VIRAL (Venus InfraRed Atmospheric gases Linker) project is aimed at proposing a remote sensing infrared (IR) spectrometer to provide first-class information on the composition and structure of the atmosphere at the top and above the cloud layer of Venus. VIRAL leverages from the legacy of a generation of spectrometers that has achieved very high detecting performances in a compact, light-weight, and easily-to-design. VIRAL will cover the IR range from 2.3 to 4.3 μm that will allow the retrieval of the layering of the Venusian upper atmosphere and its composition. The list of measured species includes CO2 and its main isotopes (with related retrievals of the atmospheric temperature), H2O and HDO (related to the evolution of water on Venus), CO, SO2, HCl, HF, H2SO4 droplets and aerosols. Its enhanced sensitivity will allow establishing refined upper limits or new detections for a number of trace gasses, such as OCS, H2S, H2CO, C2H2. An exclusive science goal is to trace phosphine, recently announced in Venus atmosphere. The concept, design and expected performance will be reported

The Venus infrared atmospheric gases linker instrument concept for solar occultation studies of Venus atmosphere composition and structure onboard the Venus Orbiter Mission of the Indian Space Research Organization

International audienceIn this paper, we describe the concept of the Venus InfraRed Atmospheric Linker (VIRAL) spectrometer for investigation of the composition and structure of the planetary atmosphere at the top and above the cloud layer of Venus onboard the Venus Orbiter Mission announced by the Indian Space Research Organization (ISRO). VIRAL includes two channels, an infrared echelle spectrometer channel and an ultra-high resolution heterodyne interferometer channel. Here, we present the concept of the echelle channel only. The instrument is designed to perform solar occultation, providing an optimal photon yield combined with a superior spectral resolving power that exceeds 20,000. VIRAL echelle spectrometer will cover the wavelength range from 2.3 to 4.3 μm, and achieve high vertical resolution (with a footprint of about 1 km at the limb) to allow the detailed altitude profiling of the Venusian upper atmosphere with its composition and structure. We present the instrument concept, its preliminary optical design and science objectives of the experiment

Instrumental requirements for the study of Venus’ cloud top using the UV imaging spectrometer VeSUV

International audienceUltraviolet spectral imaging has been a powerful tool to investigate the cloud top of Venus, allowing for measurement of several minor gases (especially SO2, SO, O3), of cloud top aerosol’s microphysical properties and of atmospheric dynamics through tracking of the unevenly distributed UV absorber. After a brief review of recent UV instruments that orbited around Venus, we present the results of a state-of-the-art radiative transfer model from Marcq et al. (2020) to derive the spectral resolution and Signal-to-Noise ratio (SNR) required to derive abundances of these gases, retrieve optical properties of the aerosols beyond our current knowledge. This leads us to propose a two-channel UV hyperspectral push-broom imager called VeSUV (standing for Venusian Spectroscopy in UV) whose technical characteristics will improve on existing measurements by a factor of at least 2, and which is well suited to the integration into the payload of future low Venus orbit platforms such as the proposed EnVision mission to ESA M5 call

Monitoring Venus cloud top: the VenSpec-U spectrometer on board ESA EnVision

International audienc

The VenSpec suite on the ESA EnVision mission to Venus

International audienceThe VenSpec instrument suite is part of the payload for the ESA M5 mission proposal EnVision which is currently in a competitive Phase A study. VenSpec consists of three channels: VenSpec-M, VenSpec-H and VenSpec-U. VenSpec-M will provide near-global compositional data on rock types, weathering, and crustal evolution by mapping the Venus surface in five atmospheric windows. VenSpec-H will be dedicated to extremely high-resolution atmospheric measurements. The main objective of the VenSpec-H instrument is to detect and quantify SO2, H2O and HDO in the lower atmosphere, to enable characterization of volcanic plumes and other sources of gas exchange with the surface of Venus, complementing VenSAR and VenSpecM surface and SRS subsurface observations. VenSpec-U will monitor sulphured minor species (mainly SO and SO2) and the as yet unknown UV absorber in Venusian upper clouds and just above. In combination, VenSpec will provide unprecedented insights into the current state of Venus and its past evolution. VenSpec will perform a comprehensive search for volcanic activity by targeting atmospheric signatures, thermal signatures and compositional signatures, as well as a global map of surface compositio