Viking Research Articles

The influence of oxychlorine phases on the flash pyrolysis of polycyclic aromatic hydrocarbons and implications for mars

A variety of chlorine-bearing hydrocarbons have been detected in the chemical analyses of soil and rock samples performed on Mars with the GCMS instruments onboard the Viking landers and the SAM instrument suite onboard the Curiosity rover. These aromatic and aliphatic chlorohydrocarbons are most likely produced by chemical reactions between salts (e.g., perchlorates, chlorates) and organic molecules of martian origin either during the thermal processing of the samples in flight or generated through radiation processes happening in Mars’ near surface. To understand the influence of salts on the organic molecules during pyrolysis and identify the potential precursors of the chlorohydrocarbons detected on Mars, we performed a systematic study and pyrolyzed three polycyclic aromatic hydrocarbons (PAHs)—naphthalene, phenanthrene, and benzanthracene—in the presence of six perchlorate and chlorate salts that have been identified or are most likely present on Mars—calcium perchlorate, iron perchlorate, sodium perchlorate, magnesium perchlorate, sodium chlorate, and potassium chlorate. Iron perchlorate had the strongest (oxy)chlorination power on the PAHs of all the salts tested whereas magnesium perchlorate and potassium chlorate were the most destructive ones. Despite the presence of these caustic salts, PAHs were highly chemically and thermally stable, suggesting they would likely be detectable natively if present in a martian sample. In addition, chlorohydrocarbons that are characteristic of the parent PAH were formed and could be used to help identify the nature of a PAH. This investigation underlines that PAHs could be the precursors of aromatic chlorohydrocarbons detected on Mars, but a definitive identification will require the detection of the parent PAHs and their respective pyrolyzates, molecules that were not yet detected on Mars likely because of the flight operating constraints of the SAM instrument.

Advancements in the 3D shape reconstruction of Phobos: An analysis of shape models and future exploration directions

Aims. Our research focuses on developing a high-precision and relatively high-resolution shape model of Phobos. Methods. We employed advanced photogrammetric techniques combined with novel computer vision methods to reconstruct the 3D shape of Phobos from nearly 900 Mars Express/SRC and Viking Orbiter images. This research also involved a comparison of the newly developed shape model with previous models to identify differences for future missions. Results. This shape model was used to generate new measurements of the volume (5740 ± 30) km3, the surface area (1629 ± 8) km2, and the bulk density (1847 ± 11) kg m−3 of Phobos. By comparing our reconstructed shape model with prior models, we have identified key differences, especially in areas such as the Opik crater and near the Shklovsky crater. These findings highlight critical areas that warrant further investigation in future missions dedicated to exploring Phobos.

Analysis of aromatic carboxylic acid and calcium salt couples with gas chromatography-mass spectrometry: Implications and comparison with in situ measurements at Mars' surface

Aromatic organic salts such as benzoates or phthalates may be widespread degradation products of organic molecules at the surface of Mars. The low volatility of these aromatic carboxylic salts could have compromised their detection through thermal extraction in situ analyses such as those performed by the Viking landers. However, over the years, analytical chemistry laboratories on board current and future Martian surface missions, such as the Sample Analysis at Mars (SAM) instrument suite on board the Curiosity rover and the Mars Organic Molecule Analyzer (MOMA) instrument of the Rosalind Franklin ExoMars rover, respectively, have evolved. These instruments have improved in efficiency to detect refractory and polar organic compounds, which could influence the detection of aromatic organic salts. To evaluate the capability of detecting aromatic organic salts on Mars with in situ instruments, we performed laboratory experiments under Viking, SAM, and MOMA-like Gas Chromatography-Mass Spectrometry (GC–MS) conditions with two carboxylic acid/salt couples: phthalic acid/calcium phthalate and benzoic acid/calcium benzoate. We studied the behavior and signatures of both molecular forms when using pyrolysis and derivatization experiments and the implications of these results in the search for organic molecules on Mars. This study showed that the Viking experiments could not have detected the presence of aromatic carboxylic salts in Martian samples because its maximum pyrolysis temperature was too low (500 °C). However, we showed that calcium benzoate and calcium phthalate, despite their refractory nature, could be identified indirectly through the detection of thermal and derivatized degradation products, both with SAM and MOMA. No conclusive proof of the presence of these aromatic organic salt species have been found in the SAM in situ data but given the right instrumental set-up they could be detected if present. The conclusions of this work raise essential questions on the detectability of refractory molecules, the analytical efficiency of flight instruments, and the interpretation of in situ data.

The habitability conditions of possible Mars landing sites for life exploration

A major focus of Mars exploration is the search for life. Since the Viking landers in the 1970's, no mission has searched for evidence of modern life. Future landed missions with this objective will require a landing site that optimizes the potential for current or geologically-recent habitable conditions. While the definition of habitability is broad, we concentrate on two conditions for habitability of temperature and water activity. In addition, we consider the access to subsurface ice (e.g., via a lander drill) as a major requirement. To examine potential landing sites, we utilize a standard model of temperature and ground-ice stability to explore a range of latitudes for the past 2.5 Myrs of orbitally induced climate change. We find that in the current epoch, habitable conditions do not occur within the ice-rich permafrost, where stable ice is limited to poleward of ∼47°N. Habitable conditions defined as favorable to metabolic activity in Earth-like potential Mars organisms did occur seasonally during periods of high obliquity >33°, when ground ice would have been more ubiquitous. The most recent occurrence was about 510 kyrs ago when temperatures and water activities seasonally exceeded the threshold for metabolic activity of −40 °C and 0.6, respectively. Periods such as these last 10s of kyrs at each occurrence. At no time or location do habitability conditions favor propagation (cell replication above −18 °C) in Earth-like Mars organisms. We present a model of subsurface stratigraphy based on the occurrence of ground ice, the age of the ice, and history of habitable conditions. From this stratigraphy we find that all latitudes offer some potential for life exploration. However, middle-latitude sites (47°N to 61°N) offer access to 100-kyr-old ice that experienced past habitable conditions, while high-latitudes sites (>61°N) offer this plus access to “ancient ice” > > 1 Myrs old. Access to, and comparison between, multiple stratigraphic layers with differing ages and histories will maximize the science results of a life exploration mission. These latitude limits may vary slightly with surface conditions of slope and soil properties.

Development of three-dimensional rotated lattice Boltzmann flux solver for the simulation of high-speed compressible flows

A three-dimensional (3D) Rotated Lattice Boltzmann Flux Solver (RLBFS) is proposed and analyzed with matrix-based linear stability theory for simulating compressible flows in a wide range of Mach numbers. The 3D RLBFS applies the finite volume method to discrete the Navier-Stokes equations and evaluates its fluxes at each cell interface. To improve numerical stability, the convective fluxes are obtained in a hybrid way by using the D1Q4 lattice Boltzmann model in two perpendicular directions decomposed by the outer normal vector of each cell interface. The viscous fluxes are computed in a conventional way using the second-order central scheme. The stability performance and order accuracy of the proposed 3D RLBFS are examined by using the matrix-based stability theory and L2 errors on different meshes respectively. It is shown that the 3D RLBFS is stable even at high Mach number and has the second-order accuracy in space. The reliability and capability of the proposed method is further evaluated by simulating several challenging compressible flow problems, including subsonic flow over the DLR-F4, transonic flow over the ONERA M6 wing, supersonic flow around NACA0012 wing, hypersonic flow over the Viking lander capsule, hypersonic flow over a hemisphere and hypersonic flow around a blunt nose double cone. The obtained numerical results are in good agreement with experimental and/or numerical data published in the literature, indicating that the present method provides a reliable and effective tool for simulating practical three-dimensional compressible flow problems in aeronautics and astronautics.

High-resolution shape models of Phobos and Deimos from stereophotoclinometry

We created high-resolution shape models of Phobos and Deimos using stereophotoclinometry and united images from Viking Orbiter, Phobos 2, Mars Global Surveyor, Mars Express, and Mars Reconnaissance Orbiter into a single coregistered collection. The best-fit ellipsoid to the Phobos model has radii of (12.95 ± 0.04) km × (11.30 ± 0.04) km × (9.16 ± 0.03) km, with an average radius of (11.08 ± 0.04) km. The best-fit ellipsoid to the Deimos model has radii of (8.04 ± 0.08) km × (5.89 ± 0.06) km × (5.11 ± 0.05) km with an average radius of (6.27 ± 0.07) km. The new shape models offer substantial improvements in resolution over existing shape models, while remaining globally consistent with them. The Phobos model resolves grooves, craters, and other surface features ~ 100 m in size across the entire surface. The Deimos model is the first to resolve geological surface features. These models, associated data products, and a searchable, coregistered collection of images across six spacecraft are publicly available in the Small Body Mapping Tool, and will be archived with the NASA Planetary Data System. These products enable an array of future studies to advance the understanding of Phobos and Deimos, facilitate coregistration of other past and future datasets, and set the stage for planning and operating future missions to the moons, including the upcoming Martian Moons eXploration (MMX) mission.Graphical

On the Prospect of Fossil Fuel on Planet Mars

Planet Mars has long been a source of attraction to astronomers and scientists. In 1976, the Viking probes inaugurated the beginning of a new era in human history by searching for primitive lifeforms on Mars. Successive Martian missions have discovered evidence, in the form of dried rivers and lake beds, of the prior abundance of water on the Martian surface leading to conjecture that, millions of years ago, some kind of primeval lifeforms, supported by chemical and biological processes, are at the origin of formation of fossil fuel on planet Mars. One hypothesis even maintains that conditions on Mars, in its early history, resembled, to a major extent, the environment reigning on Earth in its embryonic stage. Petroleum has been the outcome of this natural environment on Earth. It is argued that nascent conditions on Mars developed a fertile environment leading to the formation of fossil fuel. The aim of this paper is to investigate the prospect of such hypothesis, and to examine the likelihood that subterranean resources being extant in Mars in view of the latest data gathered by Martian probes. Analysis shows that kerogen is a viable signature of the potential presence of fossil fuel on Mars, and this result comports with preliminary findings of the Martian Rovers.

Leroy L. Cogger: A Pioneer in Optical Observations From Space

AbstractThis perspective is in memory of Leroy Leonard Cogger, a pioneer in optical imaging of the aurora and the airglow, who passed away in October 2022 in Canada at the age of 85. In his 40‐plus‐year career, which spans both space and ground‐based optical instrumentation and observations, Dr. Cogger has made significant contributions to the development of instruments for several space missions and ground observatories, including the world's first truly digital (charge‐coupled device) camera to be used in the field, the UV auroral imagers for the Swedish Viking and Freja satellites, the NASA IMAGE satellite, and the Russian INTERBALL‐2 satellite, respectively, and the fast near‐infrared auroral imager on the Canadian CASSIOPE/Enhanced Polar Outflow Probe satellite. He has also collaborated and mentored the next generation of space scientists in Canada and Europe in many areas of auroral and airglow research; he was particularly adept at combining diverse observations to provide insight into a wide array of atmospheric phenomena. His legacies go well beyond his contributions in the peer‐reviewed literature and innovative instrumentation: his scientific vision and leadership played an indispensable role in the Canadian space science research agenda, and his commitment to mentoring has left an indelible mark on many of his students and associates. He exemplified AGU's motto of “Unselfish cooperation in research.” His gentle and quiet spirit, his passion for research and in making a difference in life will be very much missed by his many friends and colleagues in Canada and abroad alike, as will his great sense of humor.

GRS contributions to flow-induced vibrations related activities in Europe

Abstract Flow-induced vibrations in nuclear power plants may lead to material fatigue, fretting wear, and eventually to loss of component integrity. The consequences might be substantial costs due to long unplanned outages or a fault that requires safety provisions to perform as intended. To avoid these, Fluid-Structure Interaction analyses are performed to understand and predict the complex thermal-hydraulic and structural mechanics phenomena. To further advance the knowledge of solving FSI problems with the help of numerical tools, in the beginning of 2020, the joint industry VIKING project was established in Europe. Further, OECD/NEA initiated in 2021 an FSI Benchmark on FIV that should be finished by the end of 2022 and the final synthesis report should be published in 2023. This paper provides a short overview of the GRS contributions within these two international activities on the prediction of FIV in nuclear power reactors. The content of this article was initially presented at the 33rd German CFD Network of Competence Meeting, held on March 22–23 at GRS in Garching, Germany.

A Prolific Innovator: Dr. Helena Wisniewski [WIE From Around the World

Dr. Helena Wisniewski’s father was an engineer who worked on the Viking Mars Landing—his patented actuator was on the landing vehicle—and her mother was a kindergarten teacher. Every Sunday, her grandfather used to arrive at her house with puzzles for her to solve, each one harder than the last, and he delighted in seeing her master them. In high school, she would pick up her father’s engineering books and apply them to her own coursework. She had a passion and an aptitude for math, and she would go on to study mathematics at William Paterson University, where she became a distinguished alumnus, and Stevens Institute of Technology before receiving her Ph.D. degree in mathematics from the Graduate Center of the City University of New York.

In situ organic biosignature detection techniques for space applications

The search for life in Solar System bodies such as Mars and Ocean Worlds (e.g., Europa and Enceladus) is an ongoing and high-priority endeavor in space science, even ∼ five decades after the first life detection mission at Mars performed by the twin Viking landers. However, thein situdetection of biosignatures remains highly challenging, both scientifically and technically. New instruments are being developed for detecting extinct or extant life on Mars and Ocean Worlds due to new technology and fabrication techniques. These instruments are becoming increasingly capable of both detecting and identifyingin situorganic biosignatures that are indicative of life and will play a pivotal role in the search for evidence of life through robotic lander missions. This review article gives an overview of techniques used for space missions (gas chromatography, mass spectrometry, and spectroscopy), the further ongoing developments of these techniques, and ion mobility spectrometry. In addition, current developments of techniques used in the next-generation instruments for organic biosignature detection are reviewed; these include capillary electrophoresis, liquid chromatography, biosensors (primarily immunoassays), and nanopore sensing; whereas microscopy, biological assays, and isotope analysis are beyond the scope of this paper and are not covered.

Superthermal electron’s effects on lump solitons structures in magnetized auroral plasma

Based on the considerations of the acknowledgements of the numerous space observations by satellites in the auroral plasma, astrophysics plasmas, spacecraft observations, various plasma models have been framed and revealed different interesting features, like electrostatic structures, solitary waves, double layers, supersolitons, etc. Soliton theory is a very efficient and competent way to describe nonlinear features. Using Viking satellite data in the auroral plasma, we have derived lump soliton solutions of the Kadomstev-Petviashvili (KP) equation by employing Hirota bilinear method. Due to its wide range of applications, the study of lump soliton is very attractive and important too. It has been shown that the lump solitons structures as well as in the one-dimensional form of lump soliton are varied with associated parameters in the auroral magnetized plasma. During the analysis of the features of the lump solitons, it is found that the system parameters play a pivotal role on the lump solitons structures.

Different Levels of Complexity for Integrating Textured Extra-terrestrial Elevation Data in Game Engines for Educational Augmented and Virtual Reality Applications

Elevation and visual data from Chang’E-2, Mars Viking, and MOLA were transformed into 3D models and environments using unity and unreal engine to be implemented in augmented (AR) and virtual reality (VR) applications, respectively. The workflows for the two game development engines and the two purposes overlap, but have significant differences stemming from their intended usage: both are used in educational settings, but while the AR app has to run on basic smartphones that students from all socio-economic backgrounds might have, the VR requires high-end PCs and can therefore make use of respective devices’ potential. Hence, the models for the AR app are reduced to the necessary components and sizes of the highest mountains on Luna and Mars, whereas the VR app contains several models of probe landing sites on Mars, a landscape containing the entire planet at multiple levels of detail and a complex environment. Both applications are enhanced for educational use with annotations and interactive elements. This study focuses on the transfer of scientific data into game development engines for the use in educational settings using the example of scales in extra-terrestrial environments.

A seismometer maps Mars’s anatomy

NASA’s InSight is the first mission to explore seismic waves in a planetary body since Apollo 17 in 1972.

Science Goals and Objectives for the Dragonfly Titan Rotorcraft Relocatable Lander

Abstract NASA’s Dragonfly mission will send a rotorcraft lander to the surface of Titan in the mid-2030s. Dragonfly's science themes include investigation of Titan’s prebiotic chemistry, habitability, and potential chemical biosignatures from both water-based “life as we know it” (as might occur in the interior mantle ocean, potential cryovolcanic flows, and/or impact melt deposits) and potential “life, but not as we know it” that might use liquid hydrocarbons as a solvent (within Titan’s lakes, seas, and/or aquifers). Consideration of both of these solvents simultaneously led to our initial landing site in Titan’s equatorial dunes and interdunes to sample organic sediments and water ice, respectively. Ultimately, Dragonfly's traverse target is the 80 km diameter Selk Crater, at 7° N, where we seek previously liquid water that has mixed with surface organics. Our science goals include determining how far prebiotic chemistry has progressed on Titan and what molecules and elements might be available for such chemistry. We will also determine the role of Titan’s tropical deserts in the global methane cycle. We will investigate the processes and processing rates that modify Titan’s surface geology and constrain how and where organics and liquid water can mix on and within Titan. Importantly, we will search for chemical biosignatures indicative of past or extant biological processes. As such, Dragonfly, along with Perseverance, is the first NASA mission to explicitly incorporate the search for signs of life into its mission goals since the Viking landers in 1976.

Four decades of understanding Martian geomorphology: Revisiting Baker’s ‘The geomorphology of Mars’

Our understanding of the Martian atmosphere, terrain and subsurface has continuously evolved over the past couple of decades as a result of a number of successful orbiter and rover missions. This prompts a need to revisit the first holistic review of Martian geomorphology, based on images from the Viking orbiters, by Victor R. Baker in 1981. Several of the interpretations and recommendations based on remote sensing in Baker’s paper are as valid today as they were four decades ago. With an unprecedented focus on Mars exploration in the coming decades, it is important to revisit the advances and prospects in Martian geomorphology research.

Olena Stepaniv Contribution to the Development of Transport Geography and Geologistics in Ukraine

Peculiarities of life, military, the diplomatic activity of Doctor of Sciences in Geography, O. I. Stepaniv, as well as her scientific achievements as a Ukrainian geographer and geologist, are revealed. Olena Stepanov was the first woman in Ukraine and the world – a military officer in the Ukrainian Sich Riflemen (Ukrainski Sichovi Striltsi, USS) and the Ukrainian Galician Army (Ukrainska Halytska Armiia, UHA) during the First World War and the Ukrainian Liberation War of 1917–1921, a diplomatic official of the Western Ukrainian People’s Republic and the Ukrainian People’s Republic. Having a doctorate in geography and history, she made a significant contribution to the development of Ukrainian geographical science, including economic and social geography, as well as transport geography and modern understanding of geologistics. The last two areas of geographical science are most fully disclosed in her work “Modern Lviv”, which provides a comprehensive description of the transport infrastructure of Lviv and Lviv region and its importance in the transport system of Ukraine, in particular, emphasizes the central position of Lviv as a transport and logistics hub on the trans-European way connecting the Baltic and Black Seas; identified the main transport routes of Lviv region, important on a national scale; in addition to the main roads, regional and local ones were identified and characterized. The characteristics of transport routes were combined with the indication of the most significant industrial enterprises of Lviv region; tourist and recreational areas and centres which were located on the ways of transport routes were indicated, as well as the tourist specialization of these centres (in textbooks on the geography of transport of the Soviet era, it was not mentioned at all); such transport and logistics indicators as road congestion, traffic intensity on them were used, as well as their historical names were given and their significance in the past was revealed. O. I. Stepaniv’s scientific works remain relevant today. This applies not only to the problems of the geography of transport communication in modern Lviv but also to current issues of international logistics, in particular, Ukraine’s participation in the Baltic-Black Sea transport and logistics integration system. O.I. Stepaniv’s scientific works on transport geography are of direct importance to the most modern EU project in the field of transport and logistics – the Three Seas Initiative (TSI). The recent TSI Summit in Tallinn (October 19–20, 2020) highlighted the impact of the TSI on the entire Baltic-Adriatic Black Sea region. TSI is open to countries – strategic partners of the EU, including Ukraine. Although the latter is not a member of the EU, it was invited to the first TSI summit in 2016 andis currently an active participant in many projects under this Initiative, without having formal membership in the TSI. Ukraine should continue to cooperate with TSI, especially with Poland, in such important infrastructure projects as the Gdansk-Odesa highway, the railway Viking project, the development of gas infrastructure within the North-South corridor (involving Ukrainian underground storage facilities of “blue fuel”), etc.

Martian boundary layer wind profiles during the landings of Viking and InSight

Interaction between mesoscale, synoptic and planetary scale circulations on Mars can combine to produce locally complex winds that make interpretation of lander wind data a challenge. We investigate the structure of the boundary layer winds by obtaining new wind speed and directions from trajectory analysis of the Viking 1, Viking 2 and InSight landings. We use the new wind data for InSight together with a column model to investigate the near-surface winds at the InSight landing site.We use our Trajectory Model and Analysis Tool (TMAT) to verify wind data obtained by Viking lander 1 (VL-1) as it passed through a region of strong winds. This is important as the winds may be evidence of Western Boundary Currents. We constrain the vertical extent of this wind layer. We also verify the wind data for Viking lander 2 (VL-2). For VL-2 the winds remain constant from parachute deployment to lander release below which there is a large change in wind direction. For InSight our analysis indicates the wind speeds remain approximately constant with altitude. We found the wind blows from the west in the upper part of InSight's descent and from the north northwest closer to the surface.We use our new TMAT inferred wind data for InSight to initialise the winds of a column model (University of Helsinki/Finnish Meteorological Institute). We investigate the influence of slope winds on the local winds at the InSight landing site. Our results demonstrate that Martian slopes and large-scale circulations can interact in a complex way to produce the near-surface wind patterns as observed by InSight.We have been able to obtain new wind velocity data at several altitudes and locations on Mars by utilizing atmospheric modelling and the known locations of landed hardware from Mars surface missions. We have applied these new velocity data to investigate the interactions of large-scale winds and the Martian topography.

Theoretical analysis of electron acoustic shock waves in magnetized superthermal plasma with electron beam

AbstractWe have analysed the small‐amplitude non‐linear electron acoustic shock waves by taking into account the effects of electron beam in magnetized plasma. Satellite observations in different regions of the Earth's magnetosphere have shown that the electrostatic solitary waves are generally associated with electron or/and ion beams. The nonlinear Korteweg‐de‐Vries Burgers (KdVB) equation has been derived by considering the basic fluid equations and dissipation effects. The nonlinear coefficient of KdVB equation comes out to be negative. Only dip‐shaped potential structures are reported here. For the parameters discussed in this paper, we did not find positive polarity shocks. This could be due to the restrictions on the plasma parameters since we are using the fixed densities of the cold, hot, and beam electrons as observed by the Viking satellite in the auroral region. In this paper, the importance of the cold electron to hot electron temperature in conjunction with the beam speed is pointed out. Increase in beam density, kinematic viscosity, and magnetic field results in increase in the amplitude while the increase in hot electron concentration and superthermality leads to decrease in potential. The numerical analysis is presented for the parameters corresponding to the observation of burst b event by Viking satellite in the dayside auroral zone of the earth's magnetosphere.

Multimode excitation and modulational instability of beam plasma system with Tsallis-distributed electrons

In the present investigation, authors have studied the linear mode structure of electron-acoustic waves, their modulational instability and rogue wave profiles in four-component plasma system consisting of stationary ions, cold electron fluid, Tsallis-distributed hot electrons and an electron beam. By applying standard perturbation method to the fluid equations, the dispersion relation is obtained that depends on various parameters such as beam density, beam velocity, beam temperature and non-extensivity q. Based on the phase velocities, two electron-acoustic (EA) modes known as slow and fast, have been extracted as real modes for which a detailed analysis is presented. Further, the basic set of equations is reduced to nonlinear Schrodinger equation (NLSE), where the nonlinearity and dispersion coefficients compete and significantly affect the stability characteristics of EA waves. For both the modes, a comprehensive study of modulational instability and rogue wave profile has been carried out by taking into consideration the effect of non-extensivity and beam velocity. The obtained results have been compared with other research works. The present investigation may be relevant to the observation from Viking satellite in the day-side auroral zone.