The Mars Microphone onboard SuperCam

The Mars Microphone is one of the five measurement techniques of SuperCam, an improved version of the ChemCam instrument that has been functioning aboard the Curiosity rover for several years. SuperCam is located on the Rover's Mast Unit, to take advantage of the unique pointing capabilities of the rover's head. In addition to being the first instrument to record sounds on Mars, the SuperCam Microphone can address several original scientific objectives: the study of sound associated with laser impacts on Martian rocks to better understand their mechanical properties, the improvement of our knowledge of atmospheric phenomena at the surface of Mars: atmospheric turbulence, convective vortices, dust lifting processes and wind interactions with the rover itself. The microphone will also help our understanding of the sound signature of the different movements of the rover: operations of the robotic arm and the mast, driving on the rough floor of Mars, monitoring of the pumps, etc ... The SuperCam Microphone was delivered to the SuperCam team in early 2019 and integrated at the Jet Propulsion Laboratory (JPL, Pasadena, CA) with the complete SuperCam instrument. The Mars 2020 Mission launched in July 2020 and landed on Mars on February 18th 2021. The mission operations are expected to last until at least August 2023. The microphone is operating perfectly.Comment: 40 page

Aerial Seismology Using Balloon-Based Barometers

Seismology on Venus has long eluded planetary scientists due to extreme temperature and pressure conditions on its surface, which most electronics cannot withstand for mission durations required for ground-based seismic studies. We show that infrasonic (low-frequency) pressure fluctuations, generated as a result of ground motion, produced by an artificial seismic source known as a seismic hammer, and recorded using sensitive microbarometers deployed on a tethered balloon, are able to replicate the frequency content of ground motion. We also show that weak, artificial seismic activity thus produced may be geolocated by using multiple airborne barometers. The success of this technique paves the way for balloon-based aero-seismology, leading to a potentially revolutionary method to perform seismic studies from a remote airborne station on the earth and solar system objects with substantial atmospheres such as Venus and Titan

Detection of Artificially Generated Seismic Signals using Balloon-borne Infrasound Sensors

We conducted an experiment in Pahrump, Nevada, in June 2017, where artificial seismic signals were created using a seismic hammer, and the possibility of detecting them from their acoustic signature was examined. In this work, we analyze the pressure signals recorded by highly sensitive barometers deployed on the ground and on tethers suspended from balloons. Our signal processing results show that wind noise experienced by a barometer on a free‐flying balloon is lower compared to one on a moored balloon. This has never been experimentally demonstrated in the lower troposphere. While seismoacoustic signals were not recorded on the hot air balloon platform owing to operational challenges, we demonstrate the detection of seismoacoustic signals on our moored balloon platform. Our results have important implications for performing seismology in harsh surface environments such as Venus through atmospheric remote sensing

The sound of geological targets on Mars from the absolute intensity of laser-induced sparks shock waves

Inspection of geological material is one of the main goals of the Perseverance rover during its journey across the landscape of the Jezero crater in Mars. NASA's rover integrates SuperCam, an instrument capable of performing standoff characterization of samples using a variety of techniques. Among those tools, SuperCam can perform laser-induced breakdown spectroscopy (LIBS) studies to elucidate the chemical composition of the targets of interest. Data from optical spectroscopy can be supplemented by simultaneously-produced laser-produced plasma acoustics in order to expand the information acquired from the probed rocks thanks to the SuperCam's microphone (MIC) as it can be synchronized with the LIBS laser. Herein, we report cover results from LIBS and MIC during Perseverance's first 380 sols on the Martian surface. We study the correlation between both recorded signals, considering the main intrasample and environmental sources of variation for each technique, to understand their behavior and how they can be interpreted together towards complimenting LIBS with acoustics. We find that louder and more stable acoustic signals are recorded from rock with compact surfaces, i.e., low presence loose particulate material, and harder mineral phases in their composition. Reported results constitute the first description of the evolution of the intensity in the time domain of shockwaves from laser-produced plasmas on geological targets recorded in Mars. These signals are expected contain physicochemical signatures pertaining to the inspected sampling positions. As the dependence of the acoustic signal recorded on the sample composition, provided by LIBS, is unveiled, the sound from sparks become a powerful tool for the identification of mineral phases with similar optical emission spectra.Many people helped with this project in addition to the co-authors, including hardware and operation teams, and we are most grateful for their support. This project was supported in the USA by NASA’s Mars Exploration Program and in France is conducted under the authority of CNES. Research funded by projects UMA18-FEDERJA-272 from Junta de Andalucía and PID2020-119185GB-I00 from Ministerio de Ciencia e Innovacion, of Spain. P.P. is grateful to the European Union’s Next Generation EU (NGEU) plan and the Spanish Ministerio de Universidades for his Margarita Salas fellowship under the program ′′Ayudas para la Recualificacion del Sistema Universitario Español′′. RCW was funded by JPL contract 1681089. A.U was funded by NASA Mars 2020 Participating Scientist program 80NSSC21K0330. Funding for open access charge: Universidad de Málaga / CBU

The sound of a Martian dust devil

Dust devils (convective vortices loaded with dust) are common at the surface of Mars, particularly at Jezero crater, the landing site of the Perseverance rover. They are indicators of atmospheric turbulence and are an important lifting mechanism for the Martian dust cycle. Improving our understanding of dust lifting and atmospheric transport is key for accurate simulation of the dust cycle and for the prediction of dust storms, in addition to being important for future space exploration as grain impacts are implicated in the degradation of hardware on the surface of Mars. Here we describe the sound of a Martian dust devil as recorded by the SuperCam instrument on the Perseverance rover. The dust devil encounter was also simultaneously imaged by the Perseverance rover's Navigation Camera and observed by several sensors in the Mars Environmental Dynamics Analyzer instrument. Combining these unique multi-sensorial data with modelling, we show that the dust devil was around 25m large, at least 118m tall, and passed directly over the rover travelling at approximately 5ms-1. Acoustic signals of grain impacts recorded during the vortex encounter provide quantitative information about the number density of particles in the vortex. The sound of a Martian dust devil was inaccessible until SuperCam microphone recordings. This chance dust devil encounter demonstrates the potential of acoustic data for resolving the rapid wind structure of the Martian atmosphere and for directly quantifying wind-blown grain fluxes on Mars.We are most grateful for the support of the Mars 2020 project team, including hardware and operation teams. This project was supported in the US by the NASA Mars Exploration Program, and in France by CNES. It is based on observations with SuperCam embarked on Perseverance (Mars2020). The research carried out at the Jet Propulsion Laboratory, California Institute of Technology, is under a contract with the National Aeronautics and Space Administration (80NM0018D0004). The JPL co-author (M.T.) acknowledges funding from NASA’s Space Technology Mission Directorate and the Science Mission Directorate. A. V-R is supported by the Spanish State Research Agency (AEI) Project No. MDM-2017-0737 Unidad de Excelencia “María de Maeztu”- Centro de Astrobiología (INTA-CSIC), and by the Comunidad de Madrid Project S2018/NMT-4291 (TEC2SPACE-CM). R.H. and A.S-L. were supported by Grant PID2019-109467GB-I00 funded by MCIN/AEI/10.13039/501100011033/ and by Grupos Gobierno Vasco IT1742-22. A.M. was supported by Grant PRE2020-092562 funded by MCIN/AEI/10.13039/501100011033 and by “ESF Investing in your future”. R.L. acknowledges InSight PSP Grant 80NSSC18K1626 as well as the Mars 2020 project. B.C. is supported by the Director’s Postdoctoral Fellowship from the Los Alamos National Laboratory, grant 20210960PRD3. JA.RM., M.M, J.T and J.G-E were supported by MCIN/AEI’s Grant RTI2018-098728-B-C31

Understanding The Correlation Of Libs And Acoustic Measurements Of Rocks And Soils Found In The Traverse Of The Perseverance Rover Across The Jezero Crater, Mars

The SuperCam instrument of the NASA MARS 2020 Perseverance rover combines a suite of atomic and molecular spectroscopies intended for an extensive description of rocks, soils and minerals in the surroundings of the landing site of the mission – the Jezero crater. The microphone installed on the SuperCam instrument allows the acquisition of acoustic signals resulting from the expansion of laser-induced plasmas towards the atmosphere. Apart from being affected by the propagation characteristics of the Mars atmosphere, the acoustic signal has an additional component related to the properties of the target including surface morphology, hardness, deformation parameters, and elasticity, among others. This information is currently being investigated as a complementary resource for characterization of the ablated material and may well supplement the LIBS data gathered from coincident laser shots. This talk will present SuperCam acoustic data of rocks and minerals found in the traverse of the Perseverance rover and will discuss its correlation with LIBS spectra.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Aerial Seismology Using Balloon-Based Barometers

Seismology on Venus has long eluded planetary scientists due to extreme temperature and pressure conditions on its surface, which most electronics cannot withstand for mission durations required for ground-based seismic studies. We show that infrasonic (low-frequency) pressure fluctuations, generated as a result of ground motion, produced by an artificial seismic source known as a seismic hammer, and recorded using sensitive microbarometers deployed on a tethered balloon, are able to replicate the frequency content of ground motion. We also show that weak, artificial seismic activity thus produced may be geolocated by using multiple airborne barometers. The success of this technique paves the way for balloon-based aero- seismology, leading to a potentially revolutionary method to perform seismic studies from a remote airborne station on the earth and solar system objects with substantial atmospheres such as Venus and Titan

Detection of Artificially Generated Seismic Signals Using Balloon-Borne Infrasound Sensors

Abstract We conducted an experiment in Pahrump, Nevada, in June 2017, where artificial seismic signals were created using a seismic hammer, and the possibility of detecting them from their acoustic signature was examined. In this work, we analyze the pressure signals recorded by highly sensitive barometers deployed on the ground and on tethers suspended from balloons. Our signal processing results show that wind noise experienced by a barometer on a free-flying balloon is lower compared to one on a moored balloon. This has never been experimentally demonstrated in the lower troposphere. While seismoacoustic signals were not recorded on the hot air balloon platform owing to operational challenges, we demonstrate the detection of seismoacoustic signals on our moored balloon platform. Our results have important implications for performing seismology in harsh surface environments such as Venus through atmospheric remote sensing