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An accurate knowledge of the orientation, the tidal deformability, and the gravity field of a celestial body is fundamental to provide constraints on its internal structure. These quantities may be retrieved by processing radiometric tracking and altimetry data from a probe in orbit around such body. This paper presents a method to combine altimetry crossovers with two-way Doppler tracking observations at normal equation level, using the Bernese GNSS Software and the pyXover software library. This method was applied to a proposed 200 km altitude orbiter around Callisto, a privileged destination for the upcoming phase of Solar System exploration. Enhancing "standard" Doppler tracking with altimetry generally benefited both orbit determination and a joint estimation of the orientation of the north pole and of planetary librations. The retrieval of low-degree gravity field parameters was also improved by the addition of altimetry data. However, the improvements on the estimated parameters were highly dependent on the characteristics of the simulation, e.g., the underlying topography roughness. Overall, combining radioscience with altimetry data accounted for a visible reduction of correlations among estimated parameters, while also allowing for a consistent estimation of the "vertical" Love number h 2 along with gravity. • An original method to combine altimetry crossovers and Doppler data is presented. • Applied to Callisto, this combination improves the orbit of a low altitude probe. • Low-degree gravity and orientation parameters benefit from the combination. • Combining observations allows for consistent estimations of Love numbers k 2 and h 2. [ABSTRACT FROM AUTHOR]

The Planetary Health Diet (PHD), also known as the EAT-Lancet reference diet, was developed to optimize global dietary quality while keeping the environmental impacts of food production within sustainable planetary boundaries. We calculated current national and global adherence to the PHD using the Planetary Health Dietary Index (PHDI). In addition, we used data on diet and mortality from three large US cohorts (n = 206,404 men and women, 54,536 deaths) to estimate the total and cause-specific mortality among adults 20 y of age and older that could be prevented by shifting from current diets to the reference PHD. The PHDI varied substantially across countries, although adherence was universally far from optimal (mean PHDI = 85 out of 140). By improving the global PHDI to 120, approximately 15 million deaths (27% of total deaths) could be prevented annually. Estimates of preventable deaths due to this shift ranged from 2.5 million for cardiovascular diseases to 0.7 million for neurodegenerative diseases. Our analysis suggests that adopting healthy and sustainable diets would have major direct health benefits by reducing mortality due to multiple diseases and could contribute substantially to achieving the United Nations Sustainable Development Goals. These numbers of preventable deaths are based on evidence that human biology is similar across racial and ethnic groups, but the exact numerical estimates should be interpreted with caution because some assumptions used for the calculations build on limited data. Refinement of these estimates will be possible when additional regional data on diet and mortality become available. [ABSTRACT FROM AUTHOR]

It is time for anthropology to reclaim truth and speak it to capitalist power more forcefully. The rise of post-truth and the truth of our planetary socioecological predicaments demand this. How to do so is not straightforward. Recalibrating deconstruction and finding a new balance between epistemic solidities and shifting sands is only part of the task. The greater anthropological challenge is reorienting ethnography from frictions (how "global connections" fragment) to tensions (how and why contradictory global connections came about and endure or not). To explore this reorientation, I propose a political ecology of truth and the cultivation of a planetary ethnography. Both aspire to do anthropological justice to the dramatic transformations in our dominant planetary consciousness and the contradictory socioecological predicaments this is mired in. [ABSTRACT FROM AUTHOR]

As an alternative to a model of world literature complicit with global capitalism and its ecological destruction, critics have proposed the ‘planetary turn’ to name the emergence of a mode of thinking capable of accommodating both social and ecological diversity. Global relationality in this context is understood not only as connectivity between different cultures but also that between the human and the non-human, and emphasizes not only cultural differences and interactions but also our deep embeddedness in and reliance on the ecological environment. Planetary thinking champions the dynamic entanglement between manifold peoples and cultures at the same time as it insists on the connections between the human and the physical world. This article focuses on the ways in which francophone postcolonial North African poetry also betrays a peculiar attentiveness at once to cultural hybridization and to the riches of the ecological landscape. The Moroccan Abdellatif Laâbi and the Tunisian Tahar Bekri are contemporary writers whose poetry has combined, over the last forty years or so, a passion for multilingualism and cultural exchange with a fascination with the singular plant life they discover at home and abroad. Both use both French and Arabic, though most of their work is in French, and write against the forces of oppression left by the legacies of colonialism in part by celebrating transculturality. Both also evoke a form of intimate communion with the ecological environment, and portray it as a force with agency in order to condemn the history of ecological destruction. Their ‘ecocosmopolitan’ poetry in this way proposes a salutary communality that responds in far-reaching ways to human mastery and oppression as it acts both on cultural difference and on the delicate ecology of planet.

In this work, we studied the x‐ray energy dependence of x‐ray beam diameter focused by polycapillary optics. A quantitative beam diameter–energy relation enables more accurate estimation of the element‐specific interrogation area of a sample using the compositional maps produced by a micro‐XRF system. This improves upon our ability to visualize individual beam‐diameter sized mineral grains and in turn directly benefits Planetary Instrument for X‐ray Lithochemistry (PIXL) analyses of martian soil in addition to benefitting other micro‐focused x‐ray fluorescence (XRF) systems. The spatial distribution of an array of characteristic XRF emission lines was measured by sampling via a knife‐edge approach with small motor stepping of the beam across target edges. Data taken as part of this effort, from the Planetary Flight Model (PFM), were limited to only seven beam energies corresponding to the elements Ni, Cu, Se, Ta, Au, Ti and Ba. Hence, we conducted additional analysis using JPL's lab‐based breadboard (LBB) micro‐XRF system, a system that emulates PIXL's functionality where we measured beam diameter corresponding to 18 elements: Na, Mg, Al, Si, Cl, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Ga, Ge, Se, Sr and Mo. The experimental results were also compared with Monte Carlo simulations. The beam diameter (y)–energy (x) relation that we obtained for LBB was y = 185.79 exp(−0.078x) whose exponential component was then used to get a more accurate relation for the PFM even with the limited data set: y = 227.53 exp(−0.078x). The difference in the two coefficients for the PFM and LBB stems mainly from the difference in the polycapillary optic design, and this work establishes x‐ray beam diameter versus energy relation quantitatively for both the systems. [ABSTRACT FROM AUTHOR]

This paper introduces the new Venus global ionosphere‐thermosphere model (V‐GITM) which incorporates the terrestrial GITM framework with Venus‐specific parameters, ion‐neutral chemistry, and radiative processes in order to simulate some of the observable features regarding the temperatures, composition, and dynamical structure of the Venus atmosphere from 70 to 170 km. Atmospheric processes are included based upon formulations used in previous Venus GCMs, several augmentations exist, such as improved horizontal and vertical momentum equations and tracking exothermic chemistry. Explicitly solving the momentum equations allows for the exploration of its dynamical effects on the day‐night structure. In addition, V‐GITM's use of exothermic chemistry instead of a strong heating efficiency accounts for the heating due to the solar EUV while producing comparable temperatures to empirical models. V‐GITM neutral temperatures and neutral‐ion densities are compared to upper atmosphere measurements obtained from Pioneer Venus and Venus Express. V‐GITM demonstrates asymmetric horizontal wind velocities through the cloud tops to the middle thermosphere and explains the mechanisms for sustaining the wind structure. In addition, V‐GITM produces reasonable dayside ion densities and shows that the neutral winds can carry the ions to the nightside via an experiment advecting O2+ ${\mathrm{O}}_{2}^{+}$. Plain Language Summary: We present a new, state‐of‐the‐art Venus global circulation model, the Venus global ionosphere thermosphere model. The new model will be useful for answering unknown questions about Venus' atmosphere, the physics of CO2 rich planets, and Venus missions utilizing the aerobraking maneuver. We performed many model simulations and compared the results to some of the existing Venus data sets to assess the accuracy of the model. The results showed that the dayside extreme ultraviolet heating can be captured using the dominant ion‐neutral chemistry rather than relying on simplified legacy methods. Furthermore, the cloud layer below the thermosphere has a unique wind pattern and its impact on the thermospheric temperatures and winds were explored. This work also revealed that the thin nightside ionosphere forms as a result of the transport of a single ion species. Key Points: A new, non‐hydrostatic Venus ionosphere‐thermosphere model is introduced with new physics not previously included in Venus GCMsSimulations during solar minimum conditions are used for data‐model comparisons of the temperatures, plasma, and neutral densitiesThe influence of the retrograde superrotating zonal flow is explored in relation to how it affects the neutral temperature and velocities [ABSTRACT FROM AUTHOR]

Abstract My paper approaches the theme of computational creativity by looking at uncertainty as an epistemic and aesthetic tool that must be examined to address the challenges brought to critical practice by planetary computation. It positions uncertainty as central to how the encounter of the human practitioner with non-human machines is conceptualized, and as a resource for building speculative-pragmatic paths of resistance against algorithmic capture. It proposes ways to cultivate uncertainty and use it as a design material to produce new types of knowledge that question machines’ pre-emptying manoeuvres and resist their capture of potential. The argument proposed is that uncertainty affords the production of new imaginaries of the human-machine encounter that can resist the foreclosure of futures (what will be) and are sustained instead by the uncertainty of potential (what might be) (Munster 2013). Dwelling in a space of potential – Deleuze’s virtual, or what I call a space of ‘maybes’, requires of the practitioner a repositioning of their epistemic perspective and reflecting on the following questions: how can material knowledge be made by engaging with modes of un-knowing and not-knowing in machine interaction? How can these modes of un-knowing and not-knowing be fostered as a critical and political onto-epistemological project of reinventing critical practice for the algorithmic age? (Horl et al. 2021; Hansen 2021, 2015, Pasquinelli and Joler 2020). The paper argues that the machinic unknown should be engaged with - not through the conventional paradigm that pitches human vs machine creativity and attempts to rank and score them through similarities, but rather through a (paradoxical) deepening of the unknowability at the core of the machine (Parisi) and machine’s own incommensurability (Fazi 2020). It then proposes the Chinese notion of wu wei (active non action) (Jullien 2011, 2004, 2000, 1995; Allen 2015, 2011) as a stratagem to experiment with to craft speculative-pragmatic interventions, and to augment the ‘power of maybes’ as a space of anti-production, and resisting reduction (Ito 2019).

The present paper aims at analyzing two works of contemporary Irish fiction, namely, Notes from a Coma (2005) by Mike McCormack and The Fjord of Killary (2012) by Kevin Barry. I argue that both works not only mirror what Dipesh Chakrabarty calls the ‘global’ and the ‘planetary’, but also reflect the non-human space and time scales that Timothy Morton identifies as one of the properties of hyperobjects. Moreover, the two novels are deeply rooted in the history of Ireland, and especially in the semi-peripheral position occupied by the country within the capitalist world system. The intermingling of various narrative layers together with speculative and realistic tropes conveys the epiphenomenality of our lived experience, characterized by the not-yet predictable consequences of planetary climate crisis and the ever-shifting demands of global capitalism.

In this piece of work, we provide comments on the paper: “Solar system planetary alignment triggers tides and earthquakes” by Awadh (2021). The paper claimed to undertake quantitative statistical analysis of earthquakes and planetary alignment across the world and, particularly, in the Zagros Region. As a result of his statistical analysis, he claimed that the alignment of the Earth with two planets in a straight line would generate earthquakes. However, after a careful review of the paper, we found that the analysis was qualitative in its major part. It is suffering from a lack of clarity for planetary alignment data and methods, in addition to a deficiency in earthquake data. We found that the major two tables (i.e., Tables 2 and 5) used by Awadh (2021) to demonstrate the relationship and the planetary alignment were not accurate. Our work demonstrates the problems of relying on inadequate and inappropriate datasets of Awadh’s (2021) paper. [ABSTRACT FROM AUTHOR]

Introduction to the Special Focus section: Buddhism in the Anthropocene.

Exploration of Mercury will continue in the near future with ESA/JAXA's BepiColombo mission, which will increase the number and the type of datasets, and it will take advantage of the results from NASA's MESSENGER (MErcury Surface, Space ENviroment, GEochemistry and Ranging) mission. One of the main discoveries from MESSENGER was the finding of a relatively high abundance of volatiles, and in particular of sulphur, on the surface. This discovery correlates well with the morphological evidence of pyroclastic activity and with features attributable to degassing processes like the hollows. BepiColombo will return compositional results from different spectral ranges and instruments, and, in particular, among them the first results from the orbit of emissivity in the thermal infrared. Here, we investigate the results from the emissivity spectra of different samples between a binary mixture of a volcanic regolith-like for Mercury and oldhamite (CaS). The acquisitions are taken at different temperatures in order to highlight potential shifts due to both mineral variation and temperature dependence on these materials that potentially could be present in hollows. Different absorption features are present for the two endmembers, making it possible to distinguish the oldhamite with respect to the regolith bulk analogue. We show how, in the mixtures, the Christiansen feature is strongly driven by the oldhamite, whereas the Reststrahlen minima are mainly dominated by mafic composition. The spectral contrast is strongly reduced in the mixtures with respect to the endmembers. The variations of spectral features are strong enough to be measured via MERTIS, and the spectral variations are stronger in relation to the mineralogy with respect to temperature dependence. [ABSTRACT FROM AUTHOR]

We provide a critical review of research paradigms for classifying intermediate‐scale aeolian bedforms on Mars and the new terminology that has emerged. The systematic classification of bedforms has always been challenging and debated, and no paradigmatic knowledge organization system exists beyond general agreement on the importance of a distinction between ripples and dunes. The diverse aeolian landscapes of Mars have introduced further topics and challenges to these debates. We argue that Martian aeolian geomorphology's knowledge organization system for intermediate‐scale bedforms is preparadigmatic and that consensus over terminology and their definitions has not been established in the literature. A preparadigmatic science can be functional only if scientists operating in the discipline provide precise, falsifiable definitions or use abductive logic. Drawing on evidence and examples from the literature, we argue that the replacement of the conventional abductive paradigm used in bedform classification with inductive logic has created an emerging disciplinary paradigm based on scientific hesitancy and a dependence on complex inductive research structures, epitomized by the concepts of 'transverse aeolian ridges' (TARs) and 'large Martian ripples' (LMRs). We show that TAR and, increasingly, LMR are inductive constructs that have been popularized despite them causing significant confusion. Notably, we highlight how the terms are irreconcilably used as both a class of bedform and as a non‐genetic placeholder term for bedforms. Suggestions for moving beyond the need for TAR and LMR are provided, focusing on a return to more direct and local hypothesis‐driven research inspired by W.M. Davis's notion of outrageous geological hypotheses. Recent debate surrounding bedforms in Gale crater is presented as an example of the productivity of such an approach, and it is recommended that TAR and LMR no longer be used. [ABSTRACT FROM AUTHOR]

Distinguishing planetary formation and evolution pathways and understanding the origins of volatiles on planetary bodies requires determination of relative abundances and isotope ratios in the noble gases, and also of the isotope ratios in C, H, N, O and S at high precisions. Traditional planetary mass spectrometers uniquely provide excellent survey capability including the noble gas relative abundances and their isotope ratios. However, to distinguish planetary evolution models for the outer planets, stable isotope ratios in C and O require precisions of ∼10‰ or better, readily achievable with a tunable laser spectrometer (TLS). As demonstrated on the Mars Curiosity rover, and as planned for a now-selected NASA Venus mission, tunable laser spectrometers play a unique role synergistic with the capabilities of planetary mass spectrometers. The TLS technique of recording infrared absorption spectra at ultrahigh resolution (resolving power λ / δ λ ∼ 5 million) provides unambiguous detection of a wide variety of gases such as H2O, H2O2, H2CO, HOCl, NO, NO2, HNO3, N2O, O3, CO, CO2, NH3, N2H4, PH3, H2S, SO2, OCS, HCl, HF, O2, HCN, and CH4, C2H2, C2H4, C2H6 at parts-per-billion levels. Through line-depth or line-area ratio comparisons of adjacent spectral lines, planetary TLS instruments can achieve isotope ratio measurements in C, H, N, O, and S molecules at precisions of ∼1–2‰, including for the triple isotope components of O and S. Expected performance of TLS instruments for Venus, Saturn, Enceladus and Uranus will be described as constrained by actual measurements reported at Mars on the Curiosity rover. [ABSTRACT FROM AUTHOR]

With climate change and pandemics, the last few years has ushered in a planetary age. Moreover, the concept of the 'globalisation'—a totalising and capitalist‐centric concept that homogenises the entire planet into a territory to conquer—has become incapable of adequately accounting for the planetary events taking place. To date, geographical literature has used the term 'planetary' in important, but disparate ways; and in so doing, underplaying the emancipatory potential the concept has in resisting the totalising concept of the 'globalisation'. This paper looks to the wider humanities and social science to offer four propositions—materiality, human as praxis, antinational and safeguarding—the planetary can be more coherently conceptualised geographically. [ABSTRACT FROM AUTHOR]

IntroductionUnlocking the full potential of different people and organizations to address existential health threats requires shared goals and frameworks that allow people to see themselves contributing to a common and shared continuum of care. A new narrative to help people implement collective action for collective problems is needed.MethodsThis paper is draw from the co-authors experience working from the local to international level on planetary health problems.ResultsThe proposed conceptual framework expands the socioecological model of health to help formulate multilevel approaches that foster healthier circumstances for all by revealing the mutual benefits that emerge from pooling expertise, funding, and political will to solve multiple problems with coordinated investment of resources and effort. It is intended to support program planning and communication. This framework is a response to the absence of systematic attempts to concurrently counteract the social and environmental conditions leading to disease, dysfunction and deficits which is increasingly seen as being problematic, especially as the root causes of health problems and solutions converge across species, sectors, and generations. The framework is embedded in the idea of interspecies and intergenerational health equity.DiscussionEnsuring interspecies and intergenerational health equity requires each actor to fulfill their roles along the continuum while supporting the needs of others. A socio-ecological continuum of care provides bundled options that combine knowledge from different sectors, disciplines and perspectives to guide interventions over time across a comprehensive array of services and support spanning all levels of needs, species and generations.

This article outlines an emerging tendency prominent in the theory and practice of the art & technology domain to ‘horseshoe’ the urgencies of planetary-scale technology with questions traditionally associated with the philosophy of mind, conventionally placed at a much lower level-of-analysis. It delineates and problematises this trend in the theoretical plane, before considering the ‘interpersonal’, stemming from the work of Hannah Arendt, as a mediatory level of analysis, and ground from which to reconcile these contemporary concerns. This intervention acts as a methodological clarification. The implications of this shift are explored for the theorisation of ‘minor tech’ projects as scalable systems which originate at the interpersonal, but can leverage change upscale.

Although pyroxene has been detected remotely across the Solar System, limited information is available from infrared remote sensing about the Mg‐Fe composition of pyroxene, and distinguishing between augite (20 < CaSiO3 < 45) and diopside‐hedenbergite (CaSiO3 > 45) remains challenging. The characteristics of pyroxene in the intermediate infrared range (4–8 μm), meanwhile, have not been documented. Using reflectance spectra of 72 samples ranging across the pyroxene quadrilateral, we investigate the effect of variations in Mg# (Mg/[Mg + Fe] × 100) and Ca‐content on the positions of strong and well‐defined spectral bands at ∼5.1 and ∼5.3 μm in high‐Ca pyroxene and ∼5.2 in low‐Ca pyroxene. We find that the 5.1, 5.2, and 5.3 μm bands move to shorter wavelengths as Mg# increases, whereas Ca‐content does not significantly affect the positions of these bands, enabling the determination of pyroxene Mg# directly from band positions alone. We also find that the ∼5.1 μm band is significantly more distinctive in diopside‐hedenbergite and the ∼5.3 μm band significantly more so in augite. Therefore, the 5.1, 5.2, and 5.3 μm spectral bands enable discrimination among diopside‐hedenbergite, low‐Ca pyroxene, and augite. Additionally, the 5.1, 5.2, and 5.3 μm bands enable direct determination of Mg# of diopside‐hedenbergite, low‐Ca pyroxene, and augite within ±23, ±10, and ±29 mol% Mg‐Fe, respectively. Plain Language Summary: Pyroxene is one of the most common minerals in the solar system. Although infrared remote sensing has allowed spacecraft to remotely detect pyroxene on planetary bodies (including Mars, the Moon, and numerous asteroids), the Mg‐Fe composition of this mineral remains challenging to determine remotely, leaving much unknown about the crustal evolution of these bodies. We describe a new tool for remotely determining the Mg‐Fe composition of pyroxene using spectra measured in the 4–8 μm intermediate infrared range, between the wavelength ranges of the more thoroughly characterized visible‐near infrared (0.5–3 μm) and mid‐infrared (8–15 μm) ranges. Using the positions of spectral bands in the 4–8 μm range, it is possible to determine the Mg‐Fe composition of pyroxene within ±23, ±10, and ±29 mol% for diopside‐hedenbergite, low‐Ca pyroxene, and augite, remaking intermediate infrared spectroscopy an additional valuable remote sensing tool. Key Points: High‐Ca and low‐Ca pyroxene spectra have strong, distinctive bands in the intermediate infrared (4–8 μm) rangeBand positions change systematically with respect to Mg‐Fe composition across a suite of pyroxene spanning the Ca‐Fe‐Mg quadrilateralSpectra in the intermediate infrared range are valuable for remotely determining pyroxene composition [ABSTRACT FROM AUTHOR]

This article uses the resolutional relationship between digital image and planetary surface in satellite remote sensing as a lens through which to view the reliance of visual culture on mineral resources. While most studies of resolution in satellite imaging have focused on visibility and invisibility, the author argues that the equivalence between pictorial and geographic space in its cm/pixel specification offers an opportunity to consider the physical relationship between the two. The proposed inversion enables the satellite and its transmitted images to be understood as contingent upon an unsustainably extractive industrial model. The article then traces the material trajectory in geophysical prospecting applications of remote sensing, identifying a recursive loop in which images are used to produce minerals that are used to produce images. The potential geopolitical impact of this circularity is then assessed with regard to an example of future remote sensing emissions governance. In this, and many other climate-critical applications, remote sensing potentially plays a vital role, yet its instrumental gaze tends to shape the earth as an informational resource whose mineral reserves should be capitalized upon. Ultimately, the author's aim is not to denounce earth observation as ecologically untenable, but to propose that we find a measure with which to assess the planetary impact of the various aspects of industrialized visual culture. Conceiving of resolution not as a measure of pictorial space but of the terrestrial cost of producing, consuming, distributing and permanently storing digital images might enable a more relational understanding of image and ground, pixels and planet. Accounting for the inverse resolution of an image could bring the deep temporal costs of digital visual culture into focus. [ABSTRACT FROM AUTHOR]

Cosmopolitanism claims to be the most just and inclusive of mainstream approaches to the ethics and practice of world order, given its commitment to human interconnection, peace, equality, diversity, and rights, and its concern with the many globalised pathologies that entrench injustice and vulnerability across borders. Yet it has largely remained oblivious to the agency, power, and value of non-human life on a turbulent and active Earth. Without rejecting its commitments to justice for human beings, the article challenges its humanism as both morally and politically inadequate to the situation of the Anthropocene, exemplified by the simultaneous crises of climate change, mass extinction, and the COVID-19 pandemic. In answer, the article develops new grounds and principles for an interspecies cosmopolitanism, exploring how we can reimagine its ontological foundations by creating new grounding images of subjectivity, existential unity, institutional organisation, and ordering purpose. These, in turn, can support political and institutional projects to secure the rights of ecosystems and people to flourish and persist through an increasingly chaotic epoch of human dominance and multispecies vulnerability across the Anthropocene Earth. [ABSTRACT FROM AUTHOR]

This article reads two cetacean tales—"Entanglement" and "Requiem"—by the prominent South Asian writer of science fiction, Vandana Singh, to evaluate her portrayal of ordinary dimensions of living and existing in situations impacted by climate change. While cetaceans often function as an exotic alien other in science fiction and in cultural fantasies, Singh places her cetacean tales among Indigenous communities in the North Arctic region. Communities like the Inuits and the Iñupiat share relationships of collaborative reciprocity with cetaceans like belugas and bowhead whales. Deploying the geographer's Chie Sakakibara's concept of "cetaceousness"—complex, co-constitutive and quotidian relationships among humans and cetaceans in the North Arctic—this article studies Singh's merger of realism and speculation in her representation of the impact of global warming on populations for whom climate change is not a catastrophe waiting in the future, but whose effects have seeped into the minutiae of the everyday and the ordinary. [ABSTRACT FROM AUTHOR]

Observations of foreshock plasma populations at Mercury are presented utilizing measurements from the Fast Imaging Plasma Spectrometer aboard the Mercury Surface, Space Environment, Geochemistry, and Ranging spacecraft. The magnetosphere and foreshock system at Mercury exists in a unique parameter space, due to the planet's relatively weak magnetic dipole and the proximity of its orbit to the Sun. Previous investigations have therefore questioned whether there is sufficient free energy at Mercury to generate foreshock populations, due to the small spatial scale of its bow shock. The observations presented in this work show that field‐aligned beam and diffuse populations similar to those seen in the terrestrial foreshock are able to form upstream of the Hermean bow shock. The observed populations are organized by the bow shock geometry, and are associated with magnetic wave activity previously detected in Mercury's foreshock with corollaries to the terrestrial foreshock. Plain Language Summary: Upstream of a magnetized planet sitting in supersonic flow, a region is formed called the "bow shock," which acts to slow down the flow before it impacts the obstacle. Because of the dynamic magnetic field environment, the bow shock can also act to speed up a fraction of the population, directing the ions back upstream. These processes have been described at Earth; here, we document observations of nearly 40 foreshock plasma populations observed at Mercury, and compare them to the populations at Earth. Despite Mercury's proximity to the Sun relative to Earth, we find that the two foreshock environments are very similar, with a few key differences worthy of future study. Key Points: Mercury's foreshock contains diffuse and field‐aligned beam (FAB) populations with similar characteristics to the same populations at EarthDiffuse and FAB populations in Mercury's foreshock are organized according to shock geometry in a manner very similar to EarthDiffuse and FAB populations are associated with simultaneous wave activity in the magnetic field [ABSTRACT FROM AUTHOR]

Successful human space exploration requires more products than can be taken as payload. There is a need, therefore, for in-space circular manufacturing. Requirements for this include limited resource inflow, from either Earth or other planets and the generation of minimal waste. The provision of nutritious food is a clear need for human survival on the Moon or Mars and is one of the most complex to solve. Demand in large quantities, constant and reliable provision of food requires the development of specialist agricultural technologies. Here, we first review the history of space farming over the past five decades. This survey assesses the technologies which have been tested under the harsh conditions of space, identifying which modern horticultural components are applicable for in-space plant growth. We then outline which plants have been grown and under what conditions, and speculate upon the types of plants that could be selected to best nourish astronauts. Current systems are focussed on experimentation and exploration, but do not yet provide turn-key solutions for efficient food production within a long-term space exploration scenario. With that take, this review aims to provide a perspective on how an engineered closed circular environmental life-support system (ECCLES) might be constructed. To exemplify the latter, nutrient auto accumulation by biofortification is proposed through the integration of space farming and space mining, which is uncharted on Earth. • Summing up the technological improvement of space horticulture over five decades. • Reporting plants that have been grown in space, how, and the key results obtained. • Identifying potential plants and technologies for future space farming. • Introducing the engineered closed circular environmental life-support system (ECCLES). [ABSTRACT FROM AUTHOR]

Automated techniques have driven new approaches to visualising and acting upon planetary crises, such as Microsoft's Planetary Computer and Amazon's partnership with the start-up Overstory (formerly 20tree.ai). However, "planetary" machine envisioning, together with its critical theorisation, tends toward scalar equivalence and the assumption of interoperability across media, infrastructure, and optics. The "planetary" becomes a mode for and platform of seeing Earth and beyond in which AI vision systems conjoin seamlessly with a predictive imaging of the planet and have the effect of becoming mutually dependent and self-reinforcing. In this article, we argue for a more pluralistic and nonhuman set of Earth images and imaginings. We argue that such modes of imaging are multiscalar and are indebted to what Paul Edwards calls "data friction." Here materialities of both media and Earth impede the seamless movement and exchange of data involved in machine vision; and disjunctive syntheses are instead constantly being generated. We examine eccentric modes of configuring the planetary via the artwork of Tega Brain, who deploys disjunctive and nonscalable relations of climate and environment in her use of data and AI imaging techniques. In spite of considerable financial, cognitive, and affective investment to entangle Earth with machine vision, we propose instead that imaging and imagining the planetary is a radically incomplete project. Drawing on Indigenous approaches to AI development via Country Centered Design and the process philosophy of William James and others, we propose that planetary "vision" operates within a pluralistic universe of seeing, in which ongoing and radical incompleteness is core to its imaging. [ABSTRACT FROM AUTHOR]

This paper seeks to investigate the current pandemic from a New Materialist perspective. New materialist philosophy through its radical understanding of agency and subjectivity provides the tools to grapple with the viral entity without placing it within the anthropocentric frame. At the same time, New Materialism can help understand the thick mesh of intra-action between the human and the non-human. The paper will study how the human body and the viral entity each and how such a relationship calls for an ethics of responsibility. Through a close reading of New Materialist philosophers like Jane Bennett, Karen Barad, Rosi Bradoti and through the employment of their ideas such as intra-action, agential realism and operator, the paper attempts to reach at an understanding of the pandemic which is accommodative by nature. The paper also provides a planetary understanding of health and illness and argues for a "more than human" approach to health care and medical knowledge. The paper derives perspectives from Spinoza’s philosophy to understand the cellular interactions between the human cell and the viral entity.

Despite undeserved challenges to participation in the field of planetary geomorphology, women have made significant contributions in the fluvial, aeolian, and (cryo)volcanic subdisciplines. In this work, some women—in particular, women of color—are highlighted to show a part of these foundational contributions. We focused on women scientists who were working in the latter half of the 20th century, a revolutionary time for terrestrial geomorphology and the inception of the discipline of planetary geomorphology. We also focused on women working in our scientific subdisciplines so that we could provide proper context for their work. These contributions have occurred both as discoveries in terrestrial geomorphology leading to follow‐on discoveries in planetary geomorphology and through serving as educators and role models. With women increasingly achieving positions of influence both in the geo‐ and planetary sciences as in American society, this research allows us to celebrate these contributions of women and particularly women of color while looking forward to a more complete record of their past contributions and greater future achievements. [ABSTRACT FROM AUTHOR]

Jadeite is frequently reported in shocked meteorites, displaying a variety of textures and grain sizes that suggest formation by either solid-state transformation or by crystallization from a melt. Sometimes, jadeite has been identified solely on the basis of Raman spectra. Here we argue that additional characterization is needed to confidently identify jadeite and distinguish it from related species. Based on chemical and spectral analysis of three new occurrences, complemented by first-principles calculations, we show that related pyroxenes in the chemical space (Na)M2(Al)M1(Si2)TO6–(Ca)M2(Al)M1(AlSi) TO6–(⎕)M2(Si)M1(Si2)TO6 with up to 2.25 atoms Si per formula unit have spectral features similar to jadeite. However, their distinct stability fields (if any) and synthesis pathways, considered together with textural constraints, have different implications for precursor phases and estimates of impactor size, encounter velocity, and crater diameter. A reassessment of reported jadeite occurrences casts a new light on many previous conclusions about the shock histories preserved in particular meteorites. [ABSTRACT FROM AUTHOR]

The article offers information about public culture which focuses on spaces beyond the city and challenges the dominant ways of thinking about urban phenomena. It discusses the term the city fails to capture the complexities of urban spaces. It is often associated with urbanists' knowledge and data-driven language, which is not accessible to a broad audience.

Geologic maps are foundational products for natural hazard assessments but developing them for submarine areas is challenging due to a lack of physical access to the study area. In response, submarine geomorphologic maps are used to provide geologic context and spatial information on landforms and related geo-hazards for risk management. These maps are generated from remotely sensed data, e.g. digital elevation models (DEMs), which introduce unique hurdles to submarine mapping. To address this issue, we produced a workflow for applying planetary geologic mapping methods to submarine data. Using this, we created an onshore-offshore geomorphologic map of the Christiana-Santorini-Kolumbo Volcanic Group, Greece. This product can be used to enhance hazard assessments on Santorini, which is a tourist hot-spot at high risk for volcanically- and seismically-induced hazards. We present this workflow as a tool for generating uniform geomorphologic map products that will aid natural hazard assessments of submarine environments.

• Conventional climate security discussions fail to grapple with earth system science. • Climate security should be reformulated in terms of the current planetary context. • Adaptability, sustainable habitats and fossil fuel control are the key elements needed. • Major derailment risks loom if urgent climate change action isn't undertaken. Much of the discussion under the label of "climate security" focuses on potential conflicts and disruptions in peripheral locations in the global south putatively triggered by climate change. If, however the analysis starts with climate, and the earth system as the point of departure for analysis, then things look very different. The speed and scale of climate disruptions is accelerating. Earth system science suggests that urgent action is needed to deal with climate change; waiting too long may make the issue impossible to address. Framing matters in terms of a planetary condition and focusing on climate rather than national security as the starting point for analysis suggests very different policy priorities. Reframing climate security to grapple with the planetary condition requires policies that first, facilitate adaptation, second work to make sustainable habitats for humanity and third, work to drastically constrain the use of fossil fuels urgently. Here, proposals for fossil fuel non-proliferation treaties and similar measures analogous with earlier arms control agreements. This provides the security sector with a much-needed direct engagement with the causes of climate change and its resultant disruptions while simultaneously reframing climate as a matter of planetary rather than national security. Tackling climate change is a matter of urgency, and failure to so effectively in the short run my derail needed efforts later, simply because the resources to do so are no longer available. [ABSTRACT FROM AUTHOR]

The 25th Anniversary Special Issue features forty articles that reflect on the study of citizenship in the last 25 years and highlight some cultural, economic, political, and social struggles over various forms and effects of citizenship. The authors include diverse disciplines, perspectives, and trajectories and address various struggles that shape citizenship as a concept and practice in the 21st century. This introduction provides an account of the aims of this special issue rather than a summary of these contributions, which we invite readers to explore and engage. [ABSTRACT FROM AUTHOR]

Unlike those studies that conclude with a future collapsing under presentism, this article takes a fresh look at the issue of futures. To that end, the first part of the article offers a review of presentism, which amounts not to the erasure of any given future but to the proliferation of possible futures in the age of the Anthropocene. The second part sets out to identify novel futures that, while they may differ from those of presentism, do not seek to revive the future proposed by the defunct modern regime of historicity. By tracking the experience of "real utopias" bent on birthing other worlds, we can begin to map their preconditions. At the intersection of several extant regimes of historicity, the autonomous Zapatista zone that has, since 1994, arisen in southern Mexico has proven uniquely inventive; it may serve as a remarkable observatory for the appearance of unprecedented futures. [ABSTRACT FROM AUTHOR]

The article analyzes Ilija Trojanow's critical engagement with capitalist globalization and its imaginaries in his collection of reportages Der entfesselte Globus (2008; The Unleashed Globe). Trojanow's critique is animated by his interest in the idea of diversity that he understands and uses in normative and descriptive ways. But his literary world-making is also characterized by an attempt to understand a globalizing world with respect to diverse human and non-human temporalities and relations between humans and animals. His reportages thus articulate, if only marginally, a planetary knowledge that seeks to capture life on a globalized planet beyond the solely human realm to which global imaginaries largely limit themselves. The article demonstrates how such literary knowledge emerges not just from Trojanow's interest in diversity, but also from his practice of literary reportage and his understanding of reportage as a genre. [ABSTRACT FROM AUTHOR]

With rising sea levels and disappearing species as harbingers of a planet-wide existential crisis facing the Earth, this article considers the ways in which geoengineering proposals diverge from understandings of global uncertainties and threats within scholarship on the globalization of insecurity, instead identifying 'the planetary' as a distinctive space of insecurity. Working at that scale, geoengineering proposals in turn not only claim to offer technological fixes but also in the process fix – in the sense of hypostatising – the meaning of (planetary) crisis, usually circumscribed as a climate crisis. The technopolitics of planetary crisis management thus produces and sustains a wider political economy that can and should be opened up to critical reflection: given that it assumes particular understandings – and thus precludes possible alternative conceptions – of what crisis entails, and consequent sociotechnical imaginaries of how market forces, scientific knowledge, and technological infrastructures might be combined in response. [ABSTRACT FROM AUTHOR]

Arc-jet facilities have been the norm for ablation experiments used to calibrate computational models to date. However, the arc jet has a few major limitations and challenges, including non-uniform enthalpy distribution, non-equilibrium state, change of surface quality during testing and the extent of oxidation, to name but a few. A novel plasma technique for preheating axisymmetric heatshield samples in hypersonic impulse facilities is presented herein. The major aim of this innovative work is to help reduce the large variations of ablation rate predictions, space vehicle materials and missile design/testing, obtain strongly coupled hypersonic boundary layers and achieve lower cost of aerothermodynamics experiments. This present work remains one of the most highly anticipated solutions to maximise payload success and replicate high surface temperatures identical to those experienced by real flight vehicles. This work makes a useful contribution to re-entry studies under conditions that replicate the characteristics of re-entry flights. Future applications for the technique are expected to be found in hypersonic impulse facilities that can simulate the true flow energy under re-entry conditions. [ABSTRACT FROM AUTHOR]

Climate change is driving species to move. Alongside climate-driven human migrations and mobility, nonhuman species are changing where they live, in response to anthropogenic destruction of the climate and the biosphere. The article examines this less considered element of the current and future mobile planet, in search of framings that can better help us grapple with the transformations underway. It first presents some general global projections of species mobilities and presents some of the key issues raised around intersection of human and nonhuman mobility. It then turns to two elemental forces--fire and ice--whose power is increasingly visible in contemporary planetary politics. Both elements call for a consideration of deeper time horizons, alongside the immediate emergencies that these forces also bring about. The final section turns to think about the ethics, time scales, and differential politics of a fully mobile planet--one that is mobile from geological forces to earthly elements, from nonhuman species to human lives and cultures, drawing on recent work on earth mobility and speculative kinetic ethics. [ABSTRACT FROM AUTHOR]

Geologic maps are foundational products for natural hazard assessments but developing them for submarine areas is challenging due to a lack of physical access to the study area. In response, submarine geomorphologic maps are used to provide geologic context and spatial information on landforms and related geo-hazards for risk management. These maps are generated from remotely sensed data, e.g. digital elevation models (DEMs), which introduce unique hurdles to submarine mapping. To address this issue, we produced a workflow for applying planetary geologic mapping methods to submarine data. Using this, we created an onshore-offshore geomorphologic map of the Christiana-Santorini-Kolumbo Volcanic Group, Greece. This product can be used to enhance hazard assessments on Santorini, which is a tourist hot-spot at high risk for volcanically- and seismically-induced hazards. We present this workflow as a tool for generating uniform geomorphologic map products that will aid natural hazard assessments of submarine environments. [ABSTRACT FROM AUTHOR]

Traditional vibration absorbers have not often been a practical solution for attenuating low frequency drivetrain modes of vibration because of the combination of the large mass and inertia and/or low stiffness, required to tune to the desired frequency. With the goal of reducing the inertia and size of a torsional vibration absorber, a unique vibration absorber was developed. Using a planetary gearset, the effective inertia of the absorber was increased without changing its physical mass, and a torsional mode below 30 Hz was successfully attenuated with physically realizable inertia and stiffness parameters. By reducing the tuned mass, the total volume claimed by the vibration absorber and planetary gearset was up to three times less than an equivalent traditional vibration absorber. A lumped parameter torsional model was developed to determine the optimal configuration of the planetary gearset input, output, and absorber inertia as well as a method to predict the optimal tuning frequency of the planetary torsional vibration absorber. A drivetrain dynamometer setup which emulates a two-degree-of-freedom torsional system was used to experimentally test and validate the performance of two planetary torsional vibration absorber prototypes built based upon the results of the lumped parameter model. The dynamometer setup was designed to have a first torsional mode around 20 Hz in which the planetary torsional vibration absorber was designed to attenuate. Based upon the experimental results of the planetary torsional vibration absorber, a reduction of over 20 dB was achieved. [ABSTRACT FROM AUTHOR]

Can fractal analysis of a lava flow's margin enable classification of the lava's morphologic type (e.g., pāhoehoe)? Such classifications would provide insights into the rheology and dynamics of the flow when it was emplaced. The potential to classify lava flows from remotely‐sensed data would particularly benefit the analysis of flows that are inaccessible, including flows on other planetary bodies. The technique's current interpretive framework depends on three assumptions: (1) measured margin fractality is scale‐invariant; (2) morphologic types can be uniquely distinguished based on measured margin fractality; and (3) modification of margin fractality by topography, including substrate slope and confinement, would be minimal or independently recognizable. We critically evaluate these assumptions at meter scales (1–10 m) using 15 field‐collected flow margin intervals from a wide variety of morphologic types in Hawaiʻi, Iceland, and Idaho. Among the 12 margin intervals that satisfy the current framework's suitability criteria (e.g., geomorphic freshness, shallowly‐sloped substrates), we show that five exhibit notably scale‐dependent fractality and all five from lava types other than 'a'ā or pāhoehoe would be classified as one or both of those types at some scales. Additionally, an 'a'ā flow on a 15° slope (Mauna Ulu, Hawaiʻi) and a spiny pāhoehoe flow confined by a stream bank (Holuhraun, Iceland) exhibit significantly depressed fractalities but lack diagnostic signatures for these modifications. We therefore conclude that all three assumptions of the current framework are invalid at meter scales and propose a new framework to leverage the potential of the underlying fractal technique while acknowledging these complexities. Key Points: The fractality of lava flow margins is highly diverse and shows varying scale dependence, even among flows of the same morphologic typeTopographic confinement and substrate slopes can modify the fractality of a lava flow's margin without imparting a diagnostic signatureWe incorporate these complexities in a new framework for interpreting lava flow types from the meter‐scale fractality of flow margins [ABSTRACT FROM AUTHOR]

Modeling the planetary heat transport of small bodies in the early Solar System allows us to understand the geological context of meteorite samples. Conductive cooling in planetesimals is controlled by thermal conductivity, heat capacity, and density, which are functions of temperature (T). We investigate if the incorporation of the T‐dependence of thermal properties and the introduction of a nonlinear term to the heat equation could result in different interpretations of the origin of different classes of meteorites. We have developed a finite difference code to perform numerical models of a conductively cooling planetesimal with T‐dependent properties and find that including T‐dependence produces considerable differences in thermal history, and in turn the estimated timing and depth of meteorite genesis. We interrogate the effects of varying the input parameters to this model and explore the nonlinear T‐dependence of conductivity with simple linear functions. Then we apply non‐monotonic functions for conductivity, heat capacity, and density fitted to published experimental data. For a representative calculation of a 250 km radius pallasite parent body, T‐dependent properties delay the onset of core crystallization and dynamo activity by ∼40 Myr, approximately equivalent to increasing the planetary radius by 10%, and extend core crystallization by ∼3 Myr. This affects the range of planetesimal radii and core sizes for the pallasite parent body that are compatible with paleomagnetic evidence. This approach can also be used to model the T‐evolution of other differentiated minor planets and primitive meteorite parent bodies and constrain the formation of associated meteorite samples. Plain Language Summary: Meteorites are fragments of the earliest planetary bodies in our Solar System. Meteorite samples record snapshots of the temperatures and cooling rates experienced inside these small rocky bodies before they were broken apart in collisions. By taking the cooling rate recorded in a meteorite and comparing it to the cooling rates expected at different depths inside parent bodies (based on computational modeling), we can estimate what size the parent body might have been and how deep inside it the meteorite formed. Properties like thermal conductivity control how the body cools: these properties are temperature dependent, so their value changes as the body cools down. We find that including this temperature‐dependence is important when modeling meteorite parent bodies, and that assuming these properties are constant can result in different interpretations of meteorite samples. As an example, we model the parent body of stony‐iron meteorites called pallasites. We find that if you include temperature‐dependent properties, the iron core freezes 40 million years later than if you use constant thermal properties, which in turn affects in which meteorite samples you expect to find paleomagnetism records of core dynamo activity. This result has implications for the thermal evolution of other meteorite parent bodies and other minor planets in the Solar System, and the code developed can be adapted to investigate these other small bodies. Key Points: Conductivity, heat capacity, and density are temperature dependent and control the cooling of planetesimalsThe estimated depth and timing of meteorite origin changes, if temperature‐dependent properties are used to model the parent bodyTemperature‐dependent properties in a model of the pallasite parent body delay the onset of core solidification by 40 million years [ABSTRACT FROM AUTHOR]