22-EPN3-006: An Isotopic Inventory of Mars analogue environments
Visit by Michael Macey and Daniel Loy (OU, UK) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 17-25 January 2024
An international team of scientists from The Open University (OU) and the Botswana International University of Science and Technology (BIUST) conducted fieldwork across the Makgadikgadi Basin. The aim of the research conducted was to collect sediment cores and water samples to assess how viability of sulfur-cycling microbes varies across a gradient of salinities, desiccation, and UV-exposure, and how this might impact the formation of biosignatures. The timing of the trip allowed sampling across a spectrum of fluctuating environmental stressors in terms of the availability of water. During the trip, a total of 16 x 30 cm cores were collected for geochemical and microbiological characterisation. Furthermore, environmental variables were taken with pH, temperature, conductivity, redox potential, and UV monitored. The trip was a success, with the collection of ideal samples to identify the relative abundance and diversity of sulfur cycling microbes across this analogue environment.
22-EPN3-041: Study of the Dust Lifting Phenomena and Electrification Processes in a Martian Analogue Site
Visit by Gabriele Franzese (INAF-OACN, Italy) and Hezi Yizhaq (Ben-Gurion University of the Negev, Israel) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 24 July – 02 August 2023
We performed a field campaign in the Makgadikgadi Salt Pans, during the dry season, to study the local dust lifting events and test a space designed dust sensor. With these purposes, we deployed a fully equipped meteorological station with the addition of a camera system and of the MicroMED sensor, the Optical Particle Counter selected on board of the ExoMars programme to characterise in situ the martian airborne dust. Here we used the terrestrial version of MicroMED, fully representative of its Martian counterpart.
We spent one week between two sites, facing different soil and wind conditions and successfully achieving both aspects of the campaign. MicroMED was indeed able to automatically operate using a preloaded acquisition schedule during day and night, in a range going from clear to highly loaded dust conditions. The campaign has hence been truly representative of the martian expected scenario and the data will be useful for further tuning the sensor and its functioning pipeline. Moreover, MicroMED acquisitions are precious also for studying the dust lifting events, in combination with all the other installed sensors. We were indeed able to monitor two days of intense dust devil activity, performing also an image survey of the events. The acquired data are promising, being under various aspects totally new to the literature. They can hence lead to highly improve our knowledge of the dust lifting phenomenon, regarding in particular the induced electric field
22-EPN3-026: Life detection and biosignature preservation studies via lipid biomarker analysis in Makgadikgadi Salt Pan
Visit by Pablo Finkel and Laura Sánchez García (Centro de Astrobiología (CAB), CSIC-INTA, Spain) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 02-09 October 2023
In large evaporitic basins such as the Makgadikgadi Salt Pans in Botswana, a series of strategies that promote the long-term preservation of lipids take place in its immediate subsurface: protective mineral-organics interactions, halite encapsulations within matrices, salt-derived enzymatic inhibition, cellular adaptations, and entombment by chemical precipitation of minerals. These strategies, plus the high preservation potential of lipid biomarkers, crafts a recipe for optimism in regard to the state of the lipids found in Makgadikgadi, whose degradation may be effectively attenuated as their preservation is enhanced.
The main goal of this project was to collect different types of samples from the pans to characterise their lipid biomarker content to a) identify biological (molecular and isotopic) features and b) to assess lipid preservation and/or degradation. Samples with protective matrices suitable for organics preservation include halite crusts, xero-mineral matrix and silcretes from Sua Pan, as well as silcretes, calcretes and mineral precipitates found in inverted channels from a relict delta. More humid samples where these protective features may lack included surface and subsurface soil samples from concentric layered mounds believed to have formed under a water table. Nonethless, these mounds present a geomorphological analogy to the Equatorial Layered Deposits (ELD) on Mars, and given the infiltrating capillary fringe that render the Makgadikgadi mounds humid, a similar process on Mars could establish the ELDs as habitable refugia. In the laboratory, once the lipid profile of all samples is characterised, the team will proceed with irradiation studies to challenge lipid degradation in protective versus non-protective matrices.
Read the full scientific report with kind permission by Pablo Finkel and Laura Sánchez García.
22-EPN3-024: VIS-NIR and Raman measurement of clays and evaporitic products as analogs of Oxia Planum in the framework of the Rosalind Franklin rover mission
Visit by Marco Ferrari and Mauro Ciarniello (INAF-IAPS, Italy) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 11-17 September 2023
This project aimed at a sampling campaign of evaporite and sedimentary products (e.g., sulfates, clays) and deposits showing evidence of biosignatures in the Makgadikgadi Salt Pans, Botswana. Samples taken from this location will be used for VIS-NIR and Raman spectroscopy measurements in the context of the future ExoMars mission.
To achieve this, the team visited 10 different sites in the Makgadikgadi Pan area, distributed across both the Ntwentwe Pan and Sue Pan during the visit. They collected 35 samples in different forms, both loose sediments with grain sizes varying from clays to sand, and cohesive sediments such as the salt crusts that characterise the top surface of the Pan. They also collected some solid rock blocks with sizes suitable for the laboratory setup of the Ma_MISS (Mars Multispectral Imager for Subsurface Studies) instrument (i.e. blocks with a maximum size of 10x10x10 cm), to perform drilling operations and spectroscopic measurements in the wall of the borehole.
The campaign aimed to confirm the ability of the Ma_MISS instrument to detect spectral signatures of organic substances in geological samples containing biosignatures. With the spectroscopic data obtained in the laboratory on the collected samples, the team aims to build a spectral database that will be useful to the scientific community.
These activities on terrestrial analogues have proven useful for understanding life in extreme conditions and how these can be preserved in the form of biosignatures and detected by the scientific instruments that will be on board future missions to Mars. In addition, this work will help to acquire crucial preparation for the exploitation and interpretation of the scientific data that the Ma_MISS instrument will provide during the active phase of the mission.
Read the full scientific report with kind permission by Marco Ferrari and Mauro Ciarniello.
20-EPN3-70: Investigation of geomorphic features in Ntwetwe pans, Makgadikgadi Basin, Botswana, using Ground Penetrating Radar: implications for Matrial surface landforms
Visit by Mebatseyon Shawel (Addis Ababa University, Ethiopia) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 06-13 July 2023
The Makgadikgadi Basin in Botswana, covering an area of 16,000 square kilometres, is the largest salt pan in the world. Its formation is related to a tectonic episode in the Tertiary, possibly linked to the East African Rift System (EARS), which caused the subsidence and infilling with water and sediments. Changes in climate and tectonics eventually led to the drying up of the ancient lake, leaving behind the expansive salt pans we see today. The basin consists of two major pans, namely Sua and Ntwetwe, with a combined area of approximately 8,400 square kilometres. These pans are mostly flat but feature distinct geomorphic elements such as mounds and shoreline features that can be easily identified through satellite imagery. In the western part of the Ntwetwe pan, there are numerous mounds with an east-facing convex side and an average height of 5 metres. These mounds are primarily composed of fine-grained sands, calcareous sand, and occasionally contain bivalve shells. While several theories have been proposed regarding their origin, the internal sedimentary structure of these geomorphic features remains unknown.
On Mars, conical mounds are significant morphological features that have been observed and mapped in various regions. The Noachian-Hesperian climate change on Mars resulted in the deposition of crudely layered sediments in the equatorial region, where fluctuations in groundwater played a crucial role. These layered sediments, known as Equatorial Layered Deposits (ELDs), contain numerous mounds that were exposed due to impact craters. The objective of this study is to investigate the mounds in the Ntwetwe pan using geophysical methods, particularly Ground Penetrating Radar (GPR). By employing GPR, we aim to image the internal structure of these mounds and other geomorphic features, with the ultimate goal of understanding the formation and preservation of similar structures on the Martian surface.
Several sites within the Ntwetwe pan were selected for GPR survey, primarily along east-west and north-south profiles. These sites are located in the northwest, northeast, and central parts of the pan. Over a period of six days, approximately 23 kilometres of GPR data were collected. Most of the surveys utilized 50MHz antennas, while three lines were acquired using both 50MHz and 30MHz antennas to attain penetration depth as well as resolution. Preliminary results indicate clear imaging of the top 15 meters over the mounds and delta sites. However, reflections away from these structures appear to be weaker, possibly due to the high moisture content of clays on the pan floor, requiring further processing works to achieve better results.
20-EPN-24: Spectral investigation of the Makgadikgadi Salt Pans as planetary analog for ancient fluvio-lacustrine environments on Mars
Visit by Katrin Stephan and Ernst Hauber, DLR Institute of Planetary Research (Germany) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 30 July – 08 August 2022
Sedimentary environments on Mars display evidence for phyllosilicates and salts. The identification and characterisation of such minerals within ancient lacustrine environments on Mars is key to resolving its past habitability. Due to their geologic importance and their potential to preserve bio signatures (e.g. organic compounds), such deposits are prime targets for lander missions (e.g. Mars2020 and Exomars). To identify promising investigation areas and landing sites spectrometers working in the visible-near Infrared (VNIR) wavelength range are extremely useful to identify and map the surface composition of Mars and other planetary surfaces (Mars Express Omega, MRO CRISM< Cassini VIMS, Dawn VIR etc).
The Makgadikgadi Salt Pans of Botswana offer access to a depocenter in a closed basin that is characterised by clastic and chemical sediments. They are therefore an ideal analogue to collect in situ spectra at a terrestrial analogue to martian sedimentary deposits and to collect samples for investigation in the laboratory by other techniques (e.g. Raman spectroscopy). Katrin Stephan and Ernst Hauber (DLR) spent 9 days at the pans and measures a divers range of surfaces at 22 locations with a portable field spectrometer. For most of the measured sites and subsides (at most of the locations, several measurements were performed), samples were collected for further investigation in the laboratory. In parallel with the field measurements, we analyse satellite data to be able to tie the field data not only to laboratory measurements, but also to remote sensing data as we would do in planetary science.
20-EPN-28: 20-EPN-28: Microbial adaptation in the hypersaline environment of Sua Pan Evaporator Ponds in Botswana and implications for search for life on Mars
Visit by Claudia Pacelli, Italian Space Agency (Italy) and Alessia Cassaro, University of Tuscia (Italy) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 12-21 July 2022
The current conditions of the Martian surface are considered prohibitive for life as we know it, due to strong radiation, highly oxidizing conditions, concentrated evaporative salts, and relatively low water activity. The Earth hosts a multitude of extreme environments whose physico-chemical properties partly match extraterrestrial planetary bodies (e.g. Mars). Such environments are defined “analogue sites” and may offer critical test-bed for astrobiological studies in characterising the physical and chemical boundaries within which life may exist on Earth and in assessing the habitability of other planets, understanding the biological mechanisms for survival in extreme environments. For example, the Makgadikgadi desert, located in north central Botswana is considered one of the largest deserts on Earth, where the salts concentration is up to 21% of NaCl. These conditions may be compared with those detected on Mars.
Here, the main aim of this Europlanet project was to collect soil samples of Makgadikgadi salt pans in order to i) understand the adaptations of microbial systems to extreme conditions in natural terrestrial environments, ii) correlate the biodiversity with the geological context. This study is of significant interest to astrobiology investigations, allowing to assess the effects of hypersaline environment on the survival potential of microorganism and to understand if hypothetical life-forms may exist or have existed on Mars, where the concentration of chlorate salts has been detected in many different locations, from 1970s.
Report Summary:
Read the full report, published with kind permission by Dr Pacelli and Dr Cassaro.
220-EPN2-85: Preservation of Organic Matter in Paleo-Mega Lakes: Implications for Martian Biosignatures
Visit by Charlotte Spencer-Jones, Durham University, (UK) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 20-29 April 2022
The geological history of Mars indicates that this planet has transitioned between conditions that could have supported life. Extensive fluvial features on the Martian surface provides evidence for the presence of water in Martian history and suggests that Mars may have been habitable during the Noachian period (4.1-3.7 Ga). Therefore, establishing a suite of relevant and robust biosignatures diagnostic for past life remains one of the key methods for detecting extinct Martian lifeforms. Organic compounds are the fundamental building blocks of all terrestrial life and are widespread throughout the solar system with structurally diverse organic compounds detected in a range of extra-terrestrial samples.
The main aims of this fieldwork campaign (20-EPN2-085) were to collect a range of samples, including sediments, biofilms, and salts from the Makgadikgadi basin with accompanying physical data from the basin. The second phase of this study will characterise organic compounds within the samples. The outcome of this work will be to establish the key parameters that control organic compound preservation within Martian analogue environments. These results will determine biosignatures that could be identified during future Mars missions (e.g. ExoMars 2020) and thus highlight the mineralogies present that have the highest preservation potential for biosignatures.
Report Summary:
Read the full report, published with kind permission by Dr Spencer-Jones.
20-EPN-61: Life in extreme environments: Distribution and importance of far-red light driven photosynthesis to primary production in Martian-like environments
Visit by Dennis Nürnberg, Freie Universität Berlin, (Germany) and Daniel Canniffe, Liverpool University (UK) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 10-19 February 2022
The aim of this project was to confirm the richness and abundance of chlorophyll f-containing cyanobacteria, and their ability to use low-energy light to perform oxygenic photosynthesis in Martian-like environments. This study was a follow-up to a 2019 sampling trip to the sabkhas of the Western Sahara (Morocco), for which we could show that chlorophyll f-cyanobacteria are highly abundant. Here we expanded this research by collecting samples from the hypersaline environments of the Sua and Ntwetwe Pans in Makgadikgadi (Botswana). Microbial mat and rock samples containing endolithic and hypolithic phototrophs were collected. Light microscopy on site confirmed the abundance of cyanobacteria of various morphologies in most collected samples. The microbial mat samples were especially rich in cyanobacteria, forming a 1-2 mm thick layer at various depths depending on the absorption properties of the top layer.
Preliminary analyses with high-performance liquid chromatography (HPLC) in combination with hyperspectral confocal fluorescence microscopy confirmed the presence of red-shifted chlorophylls in some of these samples but to less extent as observed in the sabkhas. Genomic DNA has been extracted and will be used for sequencing and phylogenetic analyses based on 16S rRNA and specific far-red light genes. This will allow to fully evaluate the microbial diversity and their ability to perform chlorophyll f-driven oxygenic photosynthesis. In addition, the enrichment and isolation process of new chlorophyll f-containing cyanobacteria has been started by transferring the samples to growth media of various salinity and keeping them under selective far-red light illumination.
Report Summary:
Read full report, published with kind permission by Dr Nürnberg and Dr Canniffe.
Looking for clues about water circulation on Mars in the remote Makgadikgadi salt pans of Botswana
From 18 – 28 October 2021, researchers Erica Luzzi, Jacobs University (Germany) and Gene Schmidt, Università degli Studi Roma Tre (Italy) were funded by the Europlanet 2024 Research Infrastructure (RI) Transnational Access (TA) programme to visit the Makgadikgadi Salt Pans in Botsawana. The trip was led by Fulvio Franchi (Botswana International University of Science and Technology (BIUST)) who is responsible for the Botswana Planetary Field Analogue for Europlanet 2024 RI. In this guest post, Erica Luzzi reports on the field trip.
Our trip to Botswana through the Transnational Access offered by Europlanet has given us an incredible amount of surprises.
Figure 1: View of the Makgadikgadi Salt Pans. Credit: E Luzzi
In addition to the precious data that we collected, we indeed had a life-changing experience visiting one of the most remote places on Earth. From the absolute silence in the desert, to the calm and breath-taking landscapes in the savanna, for some moments we really felt like being on another planet. Among many adventures (and misadventures), we accessed this extraordinary place on Earth, where a lot has been studied but still leaving space for many mysteries: the Makgadikgadi salt pans (Fig. 1). These dry lands occupy a broad area in the savanna of Botswana, and are characterized by a mixture of clays and sulfates with recurrent morphologies related to desiccation processes, such as mud cracks (Fig. 2).
Mud cracks in the pan, formed by dessication processes typical of playa environments. Credit: E Luzzi
This area once hosted an ancient lake which, due to paucity of water, turned into a playa, namely a dry lake bed. Such dry environments are hypothesized to have occurred also on Mars, where also the same types of minerals have been detected.
Part of a line in the pan. The deployed cable followed the truck’s footprints that were guided by the GPS. Credit: E Luzzi.
By studying an analog field site that we can touch with our hands as it is located on Earth, we can get a variety of insights that may help us to better investigate the processes that shaped Mars into the planet we observe today.
In the region of Arabia Terra, on Mars, light-toned layered deposits often associated with mounds have been widely described in literature, and among other interpretations they were also attributed to playa-like environments. The aim of our work was to analyse the subsurface of the Makgadikgadi salt pans, looking for faults where water could have circulated and then contributed to the hydro-geological cycle that led to the deposition of such deposits.
We performed an Electrical Resistivity Tomography survey in different areas of the pans (Fig. 3).
This particular type of geophysical technique consists of placing a number of electrodes in the ground, carefully spacing them at an equal distance, and then applying a known current. Each material responds to the current in a different way, and many variables can influence the resistivity (e.g. porosity, water content, mineralogy, etc.). A preliminary version of the resulting images confirmed the occurrence of faults that will be better investigated after a robust post-processing of the data.
While we are still working on it, for now we can conclude that the survey has been successful and we look forward to linking our observations with the enigmatic deposits occurring in Arabia Terra, Mars.
Read more about Erica’s experiences on this thread on Twitter:
4) The team. Our group was composed by Gene Schmidt, first author of the future paper, Fulvio Franchi, prof at BIUST, Ame Thato Selepeng, prof at BIUST, Cabelo, an MSc student at BIUST, Rachel, driver at BIUST, and me. I thank them all for this extraordinary experience. 5/ pic.twitter.com/pabwcH8eC1
20-EPN2-121: Constraining the movement of groundwater and fluid expulsion within playa environments on Mars
Visit by Gene Schmidt, Università degli Studi Roma Tre (Italy) and Erica Luzzi, Jacobs University (Germany) to TA1.5 Makgadikgadi Salt Pans (Botswana). Dates of visit: 20-27 October 2021
Across the surface of Mars there is evidence of past lacustrine and evaporitic environments found within basins and craters, where often layered sedimentary deposits and hydrated minerals are observed. However, the intensity, duration and precise phases of water cycle activity during this period remain unresolved. Although several geological processes and locations on Earth have been previously proposed as examples to describe these deposits on Mars, we lack a strong visualisation of what water activity might have looked like during evaportic stages within basins and craters. The Makgadikgadi Salt Pans of Botswana, where once the Makgadikgadi Lake existed, is a present evaporitic environment rich in hydrated minerals and water activity. It is a depression located at the southwestern end of a northeast-southwest set of graben. Faults have been previously proposed to have been pathways for groundwater to enter basins and craters on Mars, which then contributed to both the deposition and alteration of the sedimentary deposits. Thus, imaging the subsurface of a similar environment on Earth can help us to better understand how water processes on Mars might have continued as the Martian global climate became drier.
By using the already established locations of the faults to the north of the pans, we used remote sensing techniques to trace the best location of the faults underneath the pans (Figures 1 and 2). We then used electrical resistivity surveys to image 70 – 150 m of the pans’ subsurface where the faults were deemed most likely to occur. This work allows us to better understand the possibilities of what the underlying lithology of rocks within filled basins and craters might look like. Furthermore, it demonstrates the scientific importance of future missions to employ subsurface imaging techniques on Mars.
From 29 September – 6 October 2021, researchers Daniel Toledo and Victor Apestigue (Instituto Nacional de Técnica Aeroespacial (INTA), Spain) were funded by the Europlanet 2024 Research Infrastructure (RI) Transnational Access (TA) programme to visit the Makgadikgadi Salt Pans in Botsawana. The trip was led by Fulvio Franchi (Botswana International University of Science and Technology (BIUST)) who is responsible for the Botswana Planetary Field Analogue for Europlanet 2024 RI. Ignacio Arruego, Javier Martinez-Oter and Felipe Serrano (INTA) also participated in the field trip.In this guest post, Daniel Toledo reports on the field trip.
The main goal of the field campaign in the Makgadikgadi Salts Pans was to study how dust is lifted into the air. For our investigation, we used the spare units of the Radiation and Dust Sensor (RDS) from the NASA Mars 2020 mission and the Sun Irradiance Sensor (SIS) from the ExoMars 2022 mission (see Figure 1), which are designed to study dust carried in the atmosphere of Mars by measuring how sunlight is scattered by the dust particles.
In addition to giving information about the properties of airbourne dust, these instruments are also sensitive to the presence of dust devils – swirling columns of sand and dust that are a common feature of desert areas on Mars and on Earth. RDS and SIS can detect the changes over time in the sky brightness produced by a dust devil, and this offers a unique opportunity for monitoring and studying such events during the Mars 2020 and ExoMars 2022 missions. However, to be able to characterise and interpret dust devil observations on Mars, we first need to understand how dust devils affect SIS and RDS signals by thorough testing and evaluation of the instruments in Mars-like conditions on Earth.
Figure 1. (Left) RDS instrument: two sets of eight photodiodes. One set is pointed upward, with each photodiode covering a different wavelength range between 250-1000 nanometres. The other set is pointed sideways, 20° above the horizon, and they are spaced 45° degrees apart in azimuth to sample all directions at a single wavelength; a zenith-pointed camera (Skycam) with special optics is designed to measure column optical depth.(Right) SIS instrument: Five detectors pointed at zenith and with different spectral bands and Fields of View (FOVs); twelve lateral detectors (six in the ultraviolet range and six in the near infrared range) pointed sideways; a micro-spectrometer pointed directly upwards (at zenith) with a spectral resolution of 10 nanometres in the 340-780 nanometres range.
Figure 2. Dust devils observed in Makgadikgadi Salt Pans (left panel) and on Mars (right panel). A typical dust devil on Mars spans from hundreds of metres to thousands of metres in diameter, with a height one-eight times as large. Dust devils of Mars are thought to account for the ~50% of the total dust budget, and they represent continuous source of lifted dust, active even outside the dust storms season. For these reasons, they have been proposed as the main mechanism able to sustain the constantly-observed dust haze in the martian atmosphere.
To achieve this goal, we planned a field campaign from 29 September to 6 October in the southern part of Makgadikgadi Salt Pans (see Figure 3), in the Pan near Mopipi town. This location is characterised by frequent dust devil events and conditions that promote the lifting of high levels of aerosols (dust and particles) into the atmosphere.
Each day of the campaign, we set up RDS and SIS at two different locations from sunrise to sunset, separated by about 25 m, along with:
Two cameras to record panoramic videos during the campaign period.
A Vaisala weather station to perform measurements of pressure, wind direction and intensity, temperature and relative humidity.
A ZEN radiometer to measure how much light was absorbed by the dust at different wavelengths.
The objective of having the two main instruments at two different locations was observe the dust lifting events from different perspectives.
During the campaign, we observed a large number of dust devils (many more than 10) and dust lifting events produced by wind gusts (over 10). For each dust lifting, we recorded the dust devil distance, the size, duration and direction. To do this, we marked out concentric circles with radii of 25, 50, 75, 100, 125 and 150 m on the ground. This information along with the videos made by the cameras, helped us to establish the amount of dust lifted by the dust devil as well as their distances from the instruments. All the data collected for each event was key to establish the RDS and SIS capabilities for dust lifting characterisation on Mars.
The first two days of the campaign were characterised by high dust-loading conditions and frequent formations of dust lifting events produced by dust devils or wind gusts. During these two days, each dust lifting event registered by the cameras was also detected by RDS and SIS, with signals showing a sharp peak at the time when the event passed within the sensors field of view. Preliminary analysis suggests that we can infer from RDS and SIS signals the difference between dust lifting events produced by dust devils and those produced by wind gusts – an important result for the observations on Mars.
Figure 3. Map indicating the location selected for carrying out the field campaign in the southern part of Makgadikgadi Salt Pans (red square) and the village Rakops (black square) where different lodges are available.
The third day of campaign had to be cancelled due to rain. This resulted in a lower dust-loading conditions in the following days, and thus the amount of dust lifted by vortices or wind gusts was smaller compared to the first two days.
Upon return to BIUST in Palapye on 6 October, we held a seminar for staff and students titled Atmospheric science on Mars: from Earth analogues to future planetary networks.
In summary, the campaign was a complete success. Our observations have demonstrated the capability of the RDS and SIS sensors to detect and characterise dust devils on Mars. The analysis of the signals along with the information acquired by the other instruments will allow us to quantitatively establish the sensors limit of detection. In addition, the rainy episode offered us the chance to study dust lifting events in different aerosol loading conditions.
20-EPN2-046: Characterising dust lifting events using the ground-based Mars-2020-RDS and ExoMars-2022-SIS radiometers
Visit by Daniel Toledo, INTA (Spain) to TA1.5 AU Makgadikgadi Salt Pans (Botswana). Dates of visit: 29 September – 06 October 2021
Report Summary:
On Mars, the airborne dust is a critical factor that drives the weather and climate of the planet. Dust devils are thought to account for the ~50 % of the total dust budget, and they represent a continuous source of dust, present even outside the dust storms period. For these reasons they have been proposed as the main mechanism able to sustain the observed dust haze of the martian atmosphere. However, additional dust devil surveys covering long diurnal periods are needed to place quantitative constraints on the cycles of these events. In this regard, the present and future observations of the Radiation and Dust Sensor (RDS) and the Sun Irradiance Sensor (SIS), which are part of NASA Mars 2020 and ESA/Roscosmos ExoMars 2022 missions, offer a unique opportunity to monitoring dust devils at high temporal resolution from sunrise to sunset, and with an excellent spatial coverage.
The main goal of the field campaign in the Makgadikgadi Salts Pans (20-EPN2-065) was to study dust lifting events using the spare units of RDS and SIS. During the campaign (29 Sept to 6 Oct 2021), a large number of dust devils (>10) and dust lifting events produced by wind gusts (>10) were observed by RDS and SIS sensors. For each case, information on distance, size, temporal duration and direction was registered. This information along with observations made by other instruments (e.g. wind speed and direction), have allowed us to study the potential RDS and SIS capabilities for dust lifting characterisation on Mars.
Europlanet 2024 RI has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 871149.
Europlanet AISBL (Association Internationale Sans But Lucratif - 0800.634.634) is hosted by the Department of Planetary Atmospheres of the Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Avenue Circulaire 3, B-1180 Brussels, Belgium.
