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Summary: Igneous processes were quite widespread in the small bodies of the Solar System (SBSS) and were initially fueled by short-lived radioisotopes, the proto-Sun, impact heating, and differentiation heating. Once they finished, long-lived radioisotopes continued to warm the active bodies of the Earth, (possibly) Venus, and the cryovolcanism of Enceladus.The widespread presence of olivine and pyroxenes in planets and also in SBSS suggests that they were not necessarily the product of igneous processes and they might have been recycled from previous nebular processes or entrained in comets from interstellar space. The difference in temperature between the inner and the outer Solar System has clearly favored thermal annealing of the olivine close to the proto-Sun. Transport of olivine within the Solar System probably occurred also due to protostellar jets and winds but the entrainment in SBSS from interstellar space would overcome the requirement of initial turbulent regime in the protoplanetary nebula.

Understanding the formation of impact craters on planetary surfaces has fundamental importance in geology, impact dynamics, and planetary sciences. The finite element-smoothed particle hydrodynamics (FE-SPH) adaptive method combines the advantages of smoothed particle hydrodynamics (SPH) and finite element method (FEM) in solving hypervelocity impact (HVI) problems. Employing FE-SPH adaptive method is a new idea for the analysis of planetary impact cratering which is different from impact-simplified arbitrary Lagrangian Eulerian (iSALE). In this paper, we establish a complete numerical model of planetary impact cratering through the FE-SPH method, including material failure criterion, thermodynamic analysis, gravity preloading, etc. We reproduce the numerical results by Collins et al. (2012) and highly consistent results are obtained through comparative analysis. This study simulates the formation process of simple and complex impact craters, and the temperature, pressure, density, and geometric shape of the impact zone can be quantitatively obtained. We further analyze the distribution of polymorphs and rock fragmentations in the impact zone based on the theories of shock metamorphism. The proposed analysis method may assist geologists in conducting geological studies. • We establish a complete numerical model of planetary impact cratering different from iSALE. • We analyze the distribution of high-pressure polymorphs based on shock metamorphism. • The FE-SPH model has higher numerical precision for planetary cratering impacts. [ABSTRACT FROM AUTHOR]

Astrotourism and related citizen science activities are becoming a major trend of a sustainable, high-quality tourism segment, core elements to the protection of Dark skies in many countries. In the Summer of 2020, in the middle of COVID pandemics, we started an initiative to train young students – Cyber-Cosmos – using an Unistellar eVscope, a smart, compact and user-friendly digital telescope that offers unprecedented opportunities for deep-sky observation and citizen science campaigns. Sponsored by the Ciência Viva Summer program, this was probably the first continuous application of this equipment in a pedagogical and citizen-science context, and in a pandemic context. Pampilhosa da Serra, home to a certified Dark Sky destination (Aldeias do Xisto) in central Portugal, was the chosen location for this project, where we expect astrotourism and citizen science to flourish and contribute to space sciences education. • Astrotourism and citizen science are core elements to the protection of Dark skies. • Smart telescopes to support science missions (Lucy, TESS, Plato, ARIEL, James Webb). • First demo activity in a COVID-19 pandemic context • Supported by Pampilhosa da Serra Space Observatory for SSA activities. • Presentation at the 72nd IAC, Dubai, United Arab Emirates, 25–29 October 2021, as paper 66604, session on space culture. [ABSTRACT FROM AUTHOR]

• A web tool that offers Space data and geological analysis of planetary surfaces. • The tool integrates geological maps for detailed planetary analyses. • Confirmed trend of Mercury craters with central pits in smooth volcanic terrains. • Evolution of scientific instruments broadens planetary geological understanding. In this work we present the improved capabilities of MATISSE (Multi-purpose Advanced Tool for Instruments for the Solar System Exploration) tool which is now able to integrate geological maps and analyze specific data based on selected parameters (target, mission, instrument, geological units and area of interest). To demonstrate the effectiveness of this approach we focused on "central pit" craters on Mercury, with particular regard to the ones exposed in the Hokusai, Victoria, and Derain quadrangles. The use of MATISSE for this application allowed us for an analysis of these morphologies, confirming a tendency for their location on volcanic terrains. The integrated research approach adopted in this study has proven to be a significant advantage in geological analysis, accelerating the process of data collection and interpretation. In conclusion, this study shows how the continuous evolution of scientific tools devoted to data handling and management based on FAIR principles, such as MATISSE, has the potential to open new perspectives in understanding planetary-scale geological processes. [ABSTRACT FROM AUTHOR]

From Jan. 6, 2019 to Feb. 18, 2019, OSIRIS-REx observed asteroid (101955) Bennu ejecting 11 plumes of dust, of which part is escaping and another part is re-captured by the asteroid. The relative magnitudes of the typical forces acting on the emitted dust are quite different from the environments of the planets and other minor planets in the solar system. Here we show that ejected dust grains from the surface of Bennu can be caught in the gravitational field of Bennu. To this end, we calculated numerically the trajectories of dust grains of various sizes, from the 0.1μm to the ten millimeter range. The shape and the fate of an emitted cloud of particles depend on the size of the grains: smaller grains form a more narrowly confined dust trail while trails formed by larger grains disperse more rapidly. Four different fates are possible for ejected dust. All grains with radius less than 1.0μm, directly re-impact on Bennu or they escape directly. In contrast, a fraction of grains with a radius larger than 10.0 μm will impact or escape only after performing a number of non-Keplerian revolutions around Bennu. Our findings show how dust grains may populate the vicinity of Bennu and other active asteroids and that they can reach interplanetary space and other celestial bodies, implying that organic matter can be transported from carbonaceous asteroids to other celestial bodies, including Earth.

Since landing on Mars, the NASA InSight lander has witnessed eight Phobos and one Deimos transits. All transits could be observed by a drop in the solar array current and the surface temperature, but more surprisingly, for several ones, a clear signature was recorded with the seismic sensors and the magnetometer. We present a preliminary interpretation of the seismometer data as temperature‐induced local deformation of the ground, supported by terrestrial analog experiments and finite‐element modeling. The magnetic signature is most likely induced by changing currents from the solar arrays. While the observations are not fully understood yet, the recording of transit‐related phenomena with high sampling rate will allow more precise measurements of the transit times, thus providing additional constraints for the orbital parameters of Phobos. The response of the seismometer can potentially also be used to constrain the thermoelastic properties of the shallow regolith at the landing site. Plain Language Summary: The geophysical lander, InSight, has been operating on the surface of Mars since November 2018. Since then, the Martian moons Phobos and Deimos have been partially blocking the Sun, as seen from the InSight landing site, multiple times. Multiple InSight instruments have been measuring the effect of those transits; this surprisingly includes the seismometer and the magnetometer. We conclude that temperature‐induced deformation and tilt are responsible for the seismic measurements. The change observed in the magnetometer measurements are most likely the result of a drop in the solar array currents. We do not observe atmospheric modulations with InSight's weather station during the transit. These observations help constrain orbital parameters of the Martian moons, and the seismometer signal might allow investigating thermoelastic properties of the shallow Martian material. Key Points: Multiple geophysical InSight instruments observe unexpected signals during Phobos transitsLocal ground deformation due to surface temperature drops explain the tilt signals seen by the seismometerThe drop in the solar array currents results in a change of the magnetic field [ABSTRACT FROM AUTHOR]

The main motivation and novel notion of this present communication is to implement the recently suggested fourth order with four stages embedded RKARMS(4,4) algorithm to examine its efficiency in reinvesting the structures of extrasolar protoplanets formed via disk instability which being presented in Paul et al. [1] (G.C. Paul, M.M. Rahman, D. Kumar, M.C. Barman, the radius spectrum of solid grains settling in gaseous giant protoplanets, Earth Sci. Inform. 6 (2013) 137–144) for the case of convective heat transfer using classical Runge-Kutta (RK) technique of order four. The results by the RKARMS(4,4) algorithm compared well with those obtained by the classical RK method of order four for any time length and found to be more suitable.

Manned Mars missions planned in the near future of very low solar activity period and hence higher than acceptable radiation doses due mainly to the Galactic Cosmic Rays (GCR), would require special techniques and technological development for maintaining the good health of the astronauts. The present study is an attempt to make an assessment and characterise the coming years in terms of solar activity and space radiation environment especially due to the abundance of highly energetic heavy ions (known as HZE charged particles). These HZE particle fluxes constitute a major hazard to the astronauts and also to the critical electronic components of the spacecraft. Recent data on the HZE species (from B to Ni) obtained from ACE spacecraft shows a clear enhancement of the particle fluxes between the solar cycle 23 and solar cycle 24 (~between SSN peaks 2002 and 2014) due to the persisting low sunspot numbers of the latter cycle. The peak values of these cosmic ray fluxes occur with a time lag of about a year of the corresponding minimum value of the sunspots of a particular 11-year cycle which is pseudo-periodic in nature. This is demonstrated by the Fourier and Wavelet transform analyses of the long duration (1700–2018) yearly mean sunspot number data. The same time series data is also used to train a Hybrid Regression Neural Network (HRNN) model to generate the predicted yearly mean sunspot numbers for the solar cycle 25 (~2019–2031). The wavelet analysis of this new series of annual sunspot numbers including the predictions up to the end of 2031 shows a clear trend of continuation of the low solar activity and hence continuation of very high HZE fluxes prevailing in Solar cycle 24 into the solar cycle 25 and perhaps beyond.

Five research areas have been the focus of the scientific work of the Specola Vaticana (Vatican Observatory) over the past twenty years: planetary sciences, stellar astronomy, extragalactic astronomy, cosmology, and the development of the Vatican Advanced Technology Telescope (VATT). The choice of research program is left to the individual astronomers, all of whom work closely with lay collaborators around the world. Notable, especially in connection with the VATT, is the close coordination of the Specola with the Steward Observatory of the University of Arizona. One unique strength of the Specola is its independence from short-term funding requirements. As a result of its stable funding, Specola astronomers can engage in long-term research programs such as surveys of meteorite properties, exoplanets, stellar clusters, and galaxy clusters, which may take ten or more years to come to fruition. In this way the Specola complements the large research programs of contemporary astronomy. [ABSTRACT FROM AUTHOR]

The need for a validated set of emotional clips to elicit emotions in more ecological experiments is increasing. Here we present the validation of a new database of emotional films, named E-MOVIE, which includes, in this first validation phase, 39 excerpts arranged in six categories, three negative (Fear, Sadness and Compassion), two positive (Erotic and Scenery) and a Neutral category. Notably, Compassion and Scenery are new in the field as they were not included in other databases. The clips in E-MOVIE are characterized by homogenous durations of approximately two minutes, which make them suitable for psychophysiological research. In order to study the affective profile prompted by each category 174 participants (112 women) rated the movies on multiple dimensions, namely valence and arousal, intensity and discreteness of the induction of one of the six basic emotions and, finally, intensity of the experience of the emotional states defined by a series of emotional adjectives. Erotic clips were effective in the elicitation of a positive emotional state, characterized by high levels of arousal and excitement. On the other hand, Fear clips (selected without blood to avoid disgust reaction) prompted an affect characterized by high arousal, low valence and high levels of reported fear and anxiety. Women reported greater unpleasantness, distress, anxiety and jittery than men to the three negative categories. Compassion clips, characterized by the depiction of crying characters, were able to induce an affective state dominated by sadness and feeling touched, consistent with an empathic reaction to emotional sufferance. Sadness clips, instead, elicited an affective state characterized by sadness together with distress and angst. We also demonstrated that clips depicting natural environments (i.e. Scenery) prompted in the viewer a surprised, inspired affective state, characterized by high valence and arousal (especially in males), a result which suggests that their past categorization as neutral stimuli was inaccurate and problematic. [ABSTRACT FROM AUTHOR]

Previous estimates of the annual mean surface temperature of Jupiter's moon, Europa, neglected the effect of the eccentricity of Jupiter's orbit around the Sun, the effect of the emissivity and heat capacity of Europa's ice, the effect of the eclipse of Europa (i.e., the relative time that Europa is within the shadow of Jupiter), the effect of Jupiter's radiation, and the effect of Europa's internal heating. Other studies concentrated on the diurnal cycle but neglected some of the above factors. In addition, to our knowledge, the seasonal cycle of the surface temperature of Europa was not estimated. Here we systematically estimate the diurnal, seasonal and annual mean surface temperature of Europa, when Europa's obliquity, emissivity, heat capacity, and eclipse, as well as Jupiter's radiation, internal heating, and eccentricity, are all taken into account. For a typical internal heating rate of 0.05Wm−2, the equator, pole, and the global and mean annual mean surface temperatures are 96 K, 46 K, and 90 K, respectively. We found that the temperature at the high latitudes is significantly affected by the internal heating, especially during the winter solstice, suggesting that measurements of high latitude surface temperatures can be used to constrain the internal heating. We also estimate the incoming solar radiation to Enceladus, the moon of Saturn.

The original form of Kepler's Third Law contains a caveat regarding the requirement of small eccentricities – a fact that has not been incorporated by the traditional Newtonian derivations. This constraint is analyzed, and a re-clarification of the real meaning of “mean distance” in the law is provided, by following up the indications given by Kepler in the Harmonices Mundi. It is shown that the modified expression for the “mean distance” not only clears up conceptual difficulties, but also removes a discrepancy found by Kepler for Mercury. Based on this re-evaluation, the result of ignoring the small-eccentricity constraint is analyzed in the Propositions XXXII-XXXVII in the Principia. It is seen that there are several conceptual and mathematical mistakes that are inevitable with the Newtonian form of Kepler's Third Law.