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The astronomical cycle characteristics of Mesozoic lacustrine fine-grained sedimentary rocks play a crucial role in understanding the formation environment of such sediments. The fine-grained sedimentary rocks of the Middle Jurassic Lianggaoshan Formation in the Sichuan Basin, China, constitute a significant lacustrine deposit. Previous research has primarily focused on its reservoir characteristics, with limited understanding of the relationship between lithofacies changes and astronomical cycles. To fill this knowledge void, we provide a continuous lacustrine core record of approximately 260 m from the XY-4 well, spanning the Lianggaoshan Formation in the Eastern Sichuan Basin. Initially, we categorized it into eight lithofacies types and established a lithologic ranking sequence based on this classification. Through time-series analysis, we identified the 405 Kyr long eccentricity cyc lecycle, 125 Kyr short eccentricity cycle, obliquity, and precession cycle. We emphasize the significance of the 125 Kyr short eccentricity cycle as the primary controlling factor during the deposition of the Lianggaoshan Formation. Subsequently, based on the 405 Kyr long eccentricity cycle, we established an age model for astronomical tuning, creating an astronomical age scale. The calculated sedimentation interval for the Lianggaoshan Formation ranges from 170.00 Ma to 172.74 Ma, spanning a total duration of 2.74 Ma. Meanwhile, the sedimentation interval for the Lower Liang 2 Submember is determined to be from 171.54 Ma to 172.52 Ma, lasting 0.98 Ma. Further comparison of TOC content and mineral composition with the orbital cycles reveals that TOC content and clay mineral content exhibit in-phase variations with the 125 Kyr short eccentricity. This characteristic contradicts the features of Cenozoic continental basins but aligns consistently with the characteristics of the Middle Triassic in North China. In contrast, silica minerals and carbonate minerals display anti-phase variations with the 125 Kyr short eccentricity. Different lithofacies demonstrate distinct responses to orbital cycles. Lithofacies characterized by higher organic matter content generally develop during the half-period with the maximum eccentricity. In contrast, lithofacies with lower organic matter content tend to occur during the half-cycle associated with the minimum eccentricity. Finally, based on the integrated analysis of lithological characteristics and astronomical cycles, we established two sedimentary modes: "Seasonally Pronounced Type" corresponding to the maximum eccentricity and "Seasonally Obscure Type" corresponding to the minimum eccentricity. • The fine-grained sedimentary rocks of the Lianggaoshan Formation can be classified into eight distinct lithofacies. • The deposition of the Lianggaoshan formation was influenced by astronomical orbital cycles. • Astronomical cycles influenced the variations in mineral composition, organic matter, and lithofacies. • Different eccentricity cycles correspond to different sedimentation patterns. [ABSTRACT FROM AUTHOR]

Precise forecasting of renewable energy production is crucial for ensuring the reliable operation of the electricity grid. Developing more accurate predictive models and computational methodologies can enhance energy production and improve overall system stability. This paper introduces a novel computational approach utilizing quaternions to calculate expected solar irradiance on a given surface. The proposed method incorporates quaternion rotations and translation vectors to model the motion of astronomical objects, both independently and in relation to each other, a factor critical for accurate irradiance estimation. This approach has the potential to replace the commonly used equatorial coordinate system-based computations, offering significant improvements in adaptability, efficiency, and accuracy. The quaternion-based method provides a 9.9% improvement in average angle deviation and a 25.46% improvement in maximum angle deviation from the ground truth of the Sun's angle of incidence, compared to the equatorial coordinate system-based model. This improvement translates to a 6.5905 kWh/m 2 discrepancy in clear sky annual irradiation between the two models, which is highly significant for solar power plants. Additionally, the proposed quaternion-based calculation is adaptable for estimating irradiation on any surface following an orbital trajectory, as well as on other planets. Moreover, the model is easily extendable to include other motions, thanks to the composition property of quaternions. The article presents the calculation methodologies of both models, performs a comparative analysis of the computational results, and presents the differences in computational efficiency between the two approaches. • Correction Factors Not Required : No correction factors needed for each GPS coordinate. • Applicability to Various Orbital Trajectories : Works with any orbital path, unlike equatorial-based method. • Extensibility for Additional Motions : Extends to handle additional motions like obliquity, nutation, and precession. • Reduced Computational Complexity : Fewer trigonometric functions mean faster, more stable calculations. • Improved Accuracy : Provides more accurate solar irradiation estimates than equatorial-based method. [ABSTRACT FROM AUTHOR]

The search for orbital cycles preserved in the sedimentary record is at the forefront of the refinement of the Geologic Time Scale. Semi-enclosed to restricted environments and epicontinental seas are suited for this type of analysis because they are very responsive to the climate conditions around the basin depocenter. This study presents the first astronomical time scale for the late Paleozoic Irati-Whitehill Sea (southern Gondwana – Paraná basin) using downhole logging of HV-44-RS. Applying orbital tuning and statistical null hypothesis techniques over the natural gamma-ray, we built two floating astronomical time scales for the same record and anchored them on a new U Pb (bentonite) numerical age of 280.8 ± 1.4 Ma. Our results place the Irati Formation between 283.68 and 280.50 ± 2.98 (orbital tuning) and 284.27–280.47 ± 1.41 Ma (null hypothesis), giving the vast epicontinental Irati-Whitehill Sea its most precise minimum duration so far of 3.16 ± 1.02–3.80 ± 0.1 Myr during the late Cisuralian. Spectral analysis suggests a depositional pattern strongly modulated by long (405-kyr) and short (∼ 100-kyr) eccentricity cycles. As an exercise, we compare one of the produced astronomical age models and recently calculated eccentricity solutions that reach the late Paleozoic interval (ZB20d). Such comparison shows a remarkable correlation in variability and amplitude with this eccentricity solution. Astronomical forcing is also related to black shale accumulation with periods of high organic carbon lasting ∼405 kyr and occurring every two long eccentricity cycles after maximum regressive surface, demonstrating a predictive pattern behind these late Cisuralian regional anoxia. Our approach indicates that the Irati Formation and other correlative southern Gondwana basins are a hotspot for cyclostratigraphy still underexplored. Furthermore, we contribute to verifying astronomical solutions in deep geological time. • The first application of cyclostratigraphy to the Irati Formation (Paraná Basin). • Orbital tuning and null hypothesis test indicate eccentricity-modulated deposition. • Two anchored astronomical time scales: 283.68 – 280.50 ± 2.98 and 284.27 – 280.47 ± 1.41 Ma. • Remarkable correlation with the new deep-time astronomical solution (ZB20d). • Black shale accumulation linked to sea level variation and Earth's 405-kyr cycle. [ABSTRACT FROM AUTHOR]

Abstract We compare supernovae and Baryon Acoustic Oscillations data to the predictions of a cosmological model of interacting dark matter and dark energy. This theoretical model can be derived from the effective field theory of Einstein–Cartan gravity with two scaling exponents δ G and δ Λ , related to the interaction between dark matter and dark energy. We perform a χ 2 fit to the data to compare and contrast it with the standard ΛCDM model. We then explore the range of parameter of the model which gives a better χ 2 than the standard cosmological model. All those results lead to tight constraints on the scaling exponents of the model. Our conclusion is that this class of models, provides a decent alternative to the ΛCDM model. [ABSTRACT FROM AUTHOR]

Abstract This paper documents a previously undescribed marine palynomorph, Doricodinium obscurum gen. et sp. nov., from Upper Cretaceous sections in the central and southern Western Interior of the USA. Although an archaeopyle has not been confirmed, a case is made here for a probable dinoflagellate cyst, possible peridinioid affinity. The type locality of D. obscurum is the Global boundary Stratotype Section and Point (GSSP) for the base of Turonian Stage, at Pueblo, Colorado, where it consistently occurs in intra-Lower to middle Turonian deposits. The taxon also occurs consistently in intra-Lower Turonian strata from the Iona-1 core, SW Texas, where astronomical age modelling gives an age range of 93.92–93.25 ± 0.12 Ma in that section. Outside the USA, it has until now only been recorded from the Cenomanian–Turonian boundary interval in Pakistan. Highlights • Description of Doricodinium obscurum gen. et sp. nov., a marine palynomorph, a probable dinoflagellate cyst. • Distribution calibrated at the GSSP for the Turonian Stage, Pueblo, Colorado. • Astronomical age modelling of its distribution in the Iona-1 core, SW Texas. [ABSTRACT FROM AUTHOR]

Abstract Solar radiation (SR) is an important data for various applications such as climate, energy and engineering. Because of this, determination and estimation of temporal and spatial variability of SR has critical importance in order to make plans and organizations for the present and the future. In this study, a deep learning method is employed for estimating the SR over 30 stations located in Turkey. The astronomical factor, extraterrestrial radiation and climatic variables, sunshine duration, cloud cover, minimum temperature and maximum temperature were used as input attributes and the output was obtained as SR. The datasets of 34 stations, spanning the dates from 2001 to 2007, were used for training and testing the model, respectively, and simulated values were compared with ground-truth values. The overall coefficient of determination, root mean square error and mean absolute error were calculated as 0.980, 0.78 MJm−2day−1 and 0.61 MJm−2day−1, respectively. Consequently, DL model has yielded very precise and comparable results for estimating daily global SR. These results are generally better than or they are comparable to many previous studies reported in literature, so one can conclude that the method can be a good alternative and be successfully applied to similar regions. Highlights • Daily GSR is estimated using deep learning approach for 34 stations in Turkey. • The effects of input attributes on the results are tested using 16 combinations. • Sunshine duration is determined as the most important input attribute. • Best results are obtained using all the inputs together. • Deep learning model yielded very precise and comparable results for estimating GSR. [ABSTRACT FROM AUTHOR]

One of the unresolved questions currently in cosmology is that of the non-linear accelerated expansion of the universe. This has been attributed to the so called Dark Energy (DE). The accelerated expansion of the universe is deduced from measurements of Type Ia supernovae. Here we propose alternate models to account for the Type Ia supernovae measurements without invoking dark energy. [ABSTRACT FROM AUTHOR]

The Aptian stage, between ∼113 and ∼121 million years ago (Ma), was punctuated by a succession of Oceanic Anoxic Events (OAEs), recording extreme global warmings, dramatic expansions of the ocean's oxygen minimum zones, along with perturbations to the biotic and carbon cycles. However, the chronology of the Aptian stage is poorly constrained, impacting the duration and timing of OAEs. Using a greatly expanded sedimentary composite record (380 m) of key outcropping sections in the Vocontian Basin (SE France) combined with available radiometric dates and correlations to a set of astronomical solutions, we provide a constrained absolute astrochronology of the Aptian stage. The 405 kyr (g Venus –g Jupiter) eccentricity astronomical timescale indicates a minimal duration of ∼9.4 Myr for the Aptian stage and an age of 122.6 ± 0.3 Ma for the base of the Aptian, consistent with radioisotope dating. We find a deviation in the periodicity of g Mercury –g Jupiter eccentricity term in the mid-Aptian stage, at ca. 117.19 ± 0.3 Ma, that we ascribe as an expression of the resonance transition σ = (g Mercury – g Jupiter) – (s Mercury – s Venus), in relation with a strong chaotic orbital motion of Mercury. Such a geological observation is supported by a concomitant resonant transition in the La2004 astronomical model. • The tuned MS data indicates a minimal duration of ∼9.4 Myr for the Aptian stage. • Our revised Aptian duration appears concordant with numerical calibration. • A shift in the g Mercury –g Jupiter eccentricity term is observed at 117.19 ± 0.3 Ma. • Geological observation is supported by a resonant transition in astronomical model. [ABSTRACT FROM AUTHOR]

Based on the equations derived in (Usanin et al., 2016) a new solution combining the observations of 30 apparitions of the comet Encke from 1911 to 2010 is obtained. For the first time in the worldwide practice the solution is obtained by using converging differential correction of all 60 observed returns of the comet, however, the deviations are still unsatisfactory. The single solution has allowed to draw some preliminary conclusions. The contributions of planetary and nongravitational perturbations to the change of the elements of the orbit during the entire period of observation are determined. The extrapolation of the solution shows that for the past two thousand years the elements of the orbit orientation could change for a half of turnover, which should be taken into account when identifying the comet and associated meteor showers in ancient records. The predictions made by Z. Sekanina and I. Ferrín about oncoming termination of the comet activity are confirmed. [ABSTRACT FROM AUTHOR]

Fuzzy Cognitive Maps (FCMs) have progressively become a well-researched and extensively used set of tools for modeling real-world, complex decision making problems. Despite their fast growth, researchers and modelers are faced with the lack of a framework to analyze such models and help them assess their performance and efficiency. Moreover, when multi-layered FCM (ML-FCM) structures are used, which consist of a rich number of nodes and interconnections organized in different layers, this need becomes imperative. The present paper introduces an integrated analysis framework and a series of steps to gather useful static and dynamic information regarding ML-FCM models, as well as to interpret the corresponding results. The proposed type of analysis provides significant information on the model's complexity, the strength of its nodes and its tendency to promote or inhibit activation levels as a result of the presence of positive or negative cycles. In addition, it offers the means to perform dynamic analysis in the form of what-if scenarios. The framework is described and assessed using real-world problems from the engineering and political decision-making domains, which demonstrate its power and usefulness. [ABSTRACT FROM AUTHOR]

The cosmological model of cold dark matter (CDM) with the dark energy and a scale-invariant adiabatic primordial power spectrum has been considered as the standard cosmological model, i.e. the ΛCDM model. Weakly interacting massive particles (WIMPs) become a prominent candidate for the CDM. Many models extended from the standard model can provide the WIMPs naturally. The standard calculations of relic abundance of dark matter show that the WIMPs are well in agreement with the astronomical observation of Ω DM h 2 ≈0.11. The WIMPs have a relatively large mass, and a relatively slow velocity, so they are easy to aggregate into clusters, and the results of numerical simulations based on the WIMPs agree well with the observational results of cosmic large-scale structures. In the aspect of experiments, the present accelerator or non-accelerator direct/indirect detections are mostly designed for the WIMPs. Thus, a wide attention has been paid to the CDM model based on the WIMPs. However, the ΛCDM model has a serious problem for explaining the small-scale structures under one Mpc. Different dark matter models have been proposed to alleviate the small-scale problem. However, so far there is no strong evidence enough to exclude the CDM model. We plan to introduce the research progress of the dark matter model based on the WIMPs, such as the WIMPs miracle, numerical simulation, small-scale problem, and the direct/indirect detection, to analyze the criterion for discriminating the “cold”, “hot”, and “warm” dark matter, and present the future prospects for the study in this field. [ABSTRACT FROM AUTHOR]

The aim of this paper is to provide geoscientists with the most accurate set of the Earth's astro-climatic parameters and daily insolation quantities, able to describe the Short-Term Orbital Forcing (STOF) as represented by the ever-changing incoming solar radiation. We provide an updated review and a pragmatic tool/database using the latest astronomical models and orbital ephemeris, for the entire Holocene and 1 kyr into the future. Our results are compared with the most important database produced for studying long-term orbital forcing showing no systematic discrepancies over the full thirteen thousand years period studied. Our detailed analysis of the periods present in STOF, as perturbed by Solar System bodies, yields a very rich dynamical modulation on annual-to-decadal timescales when compared to previous results. In addition, we addressed, for the first time, the error committed considering daily insolation as a continuous function of orbital longitudes with respect to the nominal values, i.e., calculating the corresponding daily insolation with orbital longitudes tabulated at noon . We found important relative differences up to ± 5%, which correspond to errors of 2.5 W m −2 in the daily mean insolation, for exactly the same calendar day and set of astro-climatic parameters. This previously unrecognized error could have a significant impact in both the initial and boundary conditions for any climate modeling experiment. [ABSTRACT FROM AUTHOR]

This paper presents an interplanetary optical navigation algorithm based on two spherical celestial bodies. The remarkable characteristic of the method is that key navigation parameters can be estimated depending entirely on known sizes and ephemerides of two celestial bodies, especially positioning is realized through a single image and does not rely on traditional terrestrial radio tracking any more. Actual Earth–Moon group photos captured by China’s Chang’e-5T1 probe were used to verify the effectiveness of the algorithm. From 430,000 km away from the Earth, the camera pointing accuracy reaches 0.01° (one sigma) and the inertial positioning error is less than 200 km, respectively; meanwhile, the cost of the ground control and human resources are greatly reduced. The algorithm is flexible, easy to implement, and can provide reference to interplanetary autonomous navigation in the solar system. [ABSTRACT FROM AUTHOR]

Well-dated paleoanthropological sites are critical for studying hominin evolution and dispersal, especially when related to regional or global climate change. For the rich hominin fossil record of Africa, this has been facilitated by the development of high-resolution astronomically tuned age models. So far, such age models are lacking for the Pleistocene of SE Asia with its similarly rich fossil hominin record. This study aims to develop an astronomical age model for the classical Sangiran Dome area of central Java, using a semi-quantitative grain size record of the hominin-bearing Sangiran and Bapang Formations. Two initial age models were established based on two different sets of tie points and approaches (constant sedimentation rate and Bayesian age modelling). These models, which correspond to the paleoanthropological short and long chronologies for the arrival of Homo erectus on Java, were used to convert the grain size record into a time series for time series analysis. The preferred initial age model was then used as a starting point to correlate or tune the grain size record to the LR04 benthic δ18O isotope stack. This tuning was constrained by the sudden switch in grain size from obliquity to double obliquity related cycles; this switch can be linked to the onset of the Mid-Pleistocene Transition at ∼1.2 Ma marked by a similarly abrupt change in ice age history. Two slightly different astronomical age models are presented, while a one cycle hiatus at the base of the Grenzbank cannot be excluded. These age models are in better agreement with the short paleoanthropological chronology, arguing for a late arrival of H. erectus on Java. Finally, such astronomical age models, when finalized, will provide the accurate, precise, and high-resolution age control required to gain insight into the influence of both regional and global climate change on the Pleistocene paleoenvironment and potentially the hominin population of Java. • Milankovitch cycles are recorded in the Sangiran and likely also in the Bapang Fm. • Indirect influence of obliquity through sea-level change offers the best scenario. • The onset of the MPT with an age of ∼1.2 Ma is recorded in the Upper Sangiran Fm. • The Sangiran and also the Bapang Fm can be used for astronomical tuning. • Such a tuning provides accurate and precise astronomical ages for hominin events. [ABSTRACT FROM AUTHOR]

• Municipal solid waste (MSW) seasonal variations in a Canadian city are quantified. • Both meteorological and astronomical seasons are considered in the RNN-LSTM models. • Disposal behaviors at Regina landfill appears to be sensitive to daylight hours. • The R2 of the astronomical models ranged from 0.70∼0.81. • Natural daylight hours could affect MSW disposal rates. This study quantifies seasonal variations of municipal solid waste (MSW) disposal rates in a mid-sized Canadian city with respect to both meteorological and astronomical seasons using RNN – LSTM models with a single LSTM layer and 128 units. Meteorological seasons are related to the annual temperature cycle, whereas the astronomical seasons are based on the position of Earth in relation to the Sun. It is hypothesized that the number of hours of natural daylight could also affect MSW generation rates. The use of both meteorological and astronomical seasons in waste modeling is original. During the study period, considerably higher rates in summer (417.8-418.2 tonne/day) than in winter (289.0-290.0 tonne/day) were observed. Waste disposal behaviors in winter are however more consistent, with standard deviations about 138.5-139.8 tonnes/day. The astronomical models appear to better handle extreme situations in the winter and summer. The results indicate that the astronomical models may be more appropriate in some cases. Overall, the predictive accuracy of all models are acceptable, with R2 ranging from 0.70 to 0.86. In general, meteorological models outperformed astronomical models slightly, with RMSE ranged from 72-95 tonne/day. The RMSE of the winter sets are lower, probably due to the lower disposal rates in winter. The results generally support the use of astronomical data to supplement meteorological data in waste seasonal variation studies. [ABSTRACT FROM AUTHOR]

We analyse a concept for the detection of Potentially Hazardous Asteroids (PHAs) from a space-based network of telescopes on retrograde Distant Periodic Orbits. Planar periodic orbits are designed in the Sun–Earth circular restricted three-body problem, starting from initial conditions in the Hill’s problem available from the literature. A family of retrograde orbits centred at the Earth is selected as baseline, based on their maximum distance from Earth, larger than the Earth– L 2 distance. Indeed, spacecraft on such orbits can detect PHAs incoming from the Sun direction, which could not otherwise be monitored from current Earth-based systems. A trade-off on the orbit amplitude, asteroid diameter to be detected, and the constellation size is performed considering current visible sensor telescope technology. The Chelyabinsk meteor scenario is studied and the potential warning time that could be gained with a space-based survey system with respect to an Earth based-survey system is shown. [ABSTRACT FROM AUTHOR]

The X-ray emission of magnetic intermediate mass Ap/Bp stars is reviewed and put into context of intrinsic as well as extrinsic hypotheses for its origin. New X-ray observations of Ap/Bp stars are presented and combined with an updated analysis of the available datasets, providing the largest sample of its type that is currently available. In the studied stars the X-ray detections are found predominantly among the more massive, hotter and more luminous targets. Their X-ray properties are quite diverse and beside strong soft X-ray emission significant magnetic activity is frequently present. While a connection between more powerful winds and brighter X-ray emission is expected in intrinsic models, the scatter in X-ray luminosity at given bolometric luminosity is so far unexplained and several observational features like X-ray light curves and flaring, luminosity distributions and spectral properties are often similar to those of low-mass stars. It remains to be seen if these features can be fully reproduced by magnetospheres of intermediate mass stars. The article discusses implications for magnetically confined wind-shock models (MCWS) and stellar magnetospheres under the assumption that the intrinsic model is applicable, but also examines the role of possible companions. Further, related magnetospheric phenomena are presented and an outlook on future perspectives is given. [ABSTRACT FROM AUTHOR]

Hot stars emit large amounts of X-rays, which are assumed to originate in the supersonic stellar wind. Part of the emitted X-rays is subsequently absorbed in the wind and influences its ionization state. Because hot star winds are driven radiatively, the modified ionization equilibrium affects the radiative force. We review the recent progress in modeling the influence of X-rays on the radiative equilibrium and on the radiative force. We focus particularly on single stars with X-rays produced in wind shocks and on binaries with massive components, which belong to the most luminous objects in X-rays. [ABSTRACT FROM AUTHOR]

Astronomical scheduling problem has several external conditions that change dynamically at any time during observations, like weather condition (humidity, temperature, wind speed, opacity, etc.), and target visibility conditions (target over the horizon, Sun/Moon blocking the target). Therefore, a dynamic re-scheduling is needed. An astronomical project will be scheduled as one or more Scheduling Blocks (SBs) as an atomic unit of astronomical observations. We propose a mixed integer linear programming (MILP) solution to select the best SBs, favors SBs with high scientific values, and thus maximizing the quantity of completed observation projects. The data content of Atacama Large Millimeter/Submillimeter Array (ALMA) projects of cycle 0 and cycle 1 were analyzed, and a synthetic set of tests of the real instances was created. Two configurations, one of 5000 SBs in a 3 months season and another 10,000 SBs a 6 months season were created. These instances were evaluated with excellent results. Through the testing it is showed that the MILP proposal has optimal solutions. [ABSTRACT FROM AUTHOR]

We propose a phenomenological unified model (UM) for dark matter and dark energy based on an equation of state parameter w that scales with the arctan of the redshift. The free parameters of the model are three constants: Ω b 0 , α and β . Parameter α dictates the transition rate between the matter dominated era and the accelerated expansion period. The ratio β / α gives the redshift of the equivalence between both regimes. Cosmological parameters are fixed by observational data from primordial nucleosynthesis (PN), supernovae of the type Ia (SNIa), gamma-ray bursts (GRBs) and baryon acoustic oscillations (BAOs). The calibration of the 138 GRB events is performed using the 580 SNIa of the Union2.1 data set and a new set of 79 high-redshift GRB is obtained. The various sets of data are used in different combinations to constraint the parameters through statistical analysis. The UM is compared to the Λ CDM model and their differences are emphasized. [ABSTRACT FROM AUTHOR]

In consideration of the characteristics of satellite clock bias (SCB), a grey GM(1,1) model based on the first difference method is proposed. The first differences between the SCB values of two adjacent epoches are firstly derived to obtain the corresponding first difference sequence. Then, a grey model is made based on the sequence to predict the first difference values for the time following. Finally, the predicted first difference sequence is recovered to be the corresponding predicted SCB. The clock bias data provided by the IGS (International GNSS Service) are used as the experimental data, and the cases with different lengths of modeling data and different prediction step lengths are compared and analyzed. The result shows that the prediction accuracy of this method is higher than that of traditional grey GM(1,1) model, especially for the PRN01 satellite clock, whose forecast effect is the best. With the first difference method, the model prediction accuracy and stability can be effectively improved and enhanced. This method is feasible and reliable for the relatively long term SCB prediction. [ABSTRACT FROM AUTHOR]

The lunar surface is continuously exposed to the micrometeoroid environment. Hypervelocity impacts of interplanetary dust particles with speeds around 17 km s − 1 generate secondary ejecta on the lunar surface. A dust detector placed on the moon is capable of characterizing the secondary ejecta population. The purpose of this paper is to study the speed and trajectory information of ejecta by impact simulations and its implications for the location of a dust sensor on the surface. AUTODYN15.0/2D software was used to simulate the velocity and angular distributions of ejecta created by the primary impacts of interplanetary dust particles. We considered projectiles with sizes of 10 μ m spheres in diameter with speeds of 17 km s − 1 . We used impact angles of 15°, 30°, 45°, 60°, 75°, and 90° with respect to the surface. A significant percentage of the impact ejecta are created in the early-time stage of the impact process. This population can be captured by a sensor placed on the lunar surface (e.g. Lunar Ejecta and Meteorites (LEAM) experiment) or by a sensor mounted directly on a lander (e.g. Lunar Dust eXplorer (LDX)). The secondary ejecta population above the lunar surface is considered to explain the results of the LEAM experiment. A sensor directly placed on the surface like LEAM is not very well suited to measure the high-speed ejecta component – a sensor located at a few meters height (e.g. on top of a lunar lander) would measure higher fluxes. [ABSTRACT FROM AUTHOR]

Understanding the moisture history of low latitudes from the most recent glacial period of the latest Pleistocene to post-glacial warmth in continental tropical regions is hampered by the lack of continuous time series. We conducted downhole spectral gamma (γ) ray and magnetic susceptibility logs over 300 m of lacustrine deposits of Lake Chalco (Mexico City) to reconstruct an age-depth model using an astronomical and correlative approach, and to reconstruct long-term moisture availability. Our results suggest that the Lake Chalco sediments contain several rhythmic alternations with a quasi-cyclic pattern comparable to the Pleistocene benthic stack. This allows us to calculate a time span of about 500,000 years for this sediment deposition. We developed proxies for moisture, detrital input, and salinity, all based on the physical properties of γ-ray spectroscopy and magnetic susceptibility. Our results indicate that Lake Chalco formed during Marine Isotope Stage 13 (MIS13) and the lake level gradually increased over time until the interglacial MIS9. Moisture content is generally higher during interglacials than during glacials. However, two periods, namely MIS6 and MIS4, have higher moisture contents. We developed a model by comparing the obtained moisture proxy with climatic drivers, to understand how different climate systems drove effective moisture availability in the Chalco sub-basin over the past 500,000 years. Carbon dioxide, eccentricity, and precession are all key drivers of the moisture content of Lake Chalco over the past 500,000 years. • Relative contributions of radioactive elements (K, Th, U) investigated in Lake Chalco sediments. • These contributions vary with climatic and environmental conditions over time. • The gamma (γ) ray signal of Lake Chalco sequence exhibits Earth's orbital cycles. • γ-ray radiation increase due to authigenic uranium and redox conditions in the lake bottom water. • Downhole logging data can be a key tool to unravel the climate record. [ABSTRACT FROM AUTHOR]

Although weakly interacting massive particle (WIMP) scenario is very well motivated, it is not guaranteed to be the truth. It is important to keep mind open and consider other well-motivated scenarios. In this paper, we briefly review several possible non-WIMP dark matter (DM) candidates. First, we discuss details on asymmetric DM models, in which the baryon asymmetry in standard model sector is related to the asymmetry in DM sector. We discuss how DM relic abundance is determined in such models. Also we cover the possible interesting experimental signatures induced by its asymmetric nature. Then we consider ultralight DM candidates, i.e., axion and dark photon. In such scenarios, DM should be treated as a coherently oscillating background, instead of each individual particle. Searching strategies for such DM candidates is very different than those in conventional DM models. We discuss several interesting experiments looking for these ultralight particles. We also cover interesting subtleties encountered in those experiments. [ABSTRACT FROM AUTHOR]

An improved modelling method for Pogo analysis and simulation is presented which derives differential equations instead of the differential-algebraic equations by Rubin׳s method. Firstly the classification mechanism based on the description of independent weight-displacements is proposed and nine types of independent elements are derived by division and combination of the basic physical elements. Then the differential equations of the propulsion system are established using assembly conditions that perturbational pressures on the nodes are equal to each other. The differential equations of the Pogo analysis model are then obtained by coupling the structure vibration equations and the propulsion system equations. Since the improved Pogo analysis model does not contain algebraic equations, it can be directly used for time-domain simulation and frequency-domain analysis. Moreover, the dimensions of the improved Pogo analysis model are reduced to almost half of the ones of Rubin׳s method due to the elimination of variables of perturbational pressures, which significantly improves the numerical efficiency and stability. Finally, analysis and simulation results of a certain type of CZ rocket of China confirm the correctness and practicability of the proposed modelling method. [ABSTRACT FROM AUTHOR]

The monitoring of the Earth's magnetic field time variation requires a continuous recording of geomagnetic data with a good spatial coverage over the area of study. In southern Africa, ground recording stations are limited and the use of satellite data is needed for the studies where high spatial resolution data is required. We show the fast time variation of the geomagnetic field in the southern Africa region by deriving an harmonic spline model from CHAMP satellite measurements recorded between 2001 and 2010. The derived core field model, the Southern Africa Regional Model (SARM), is compared with the global model GRIMM-2 and the ground based data recorded at Hermanus magnetic observatory (HER) in South Africa and Tsumeb magnetic observatory (TSU) in Namibia where the focus is mainly on the long term variation of the geomagnetic field. The results of this study suggest that the regional model derived from the satellite data alone can be used to study the small scale features of the time variation of the geomagnetic field where ground data is not available. In addition, these results also support the earlier findings of the occurrence of a 2007 magnetic jerk and rapid secular variation fluctuations of 2003 and 2004 in the region. [ABSTRACT FROM AUTHOR]

The classical inversion of Global Positioning System (GPS) Ionospheric Radio Occultation (IRO) data is Abel inversion method, in which the spherical symmetry of the ionospheric electron density distribution is assumed. This assumption can cause some errors for the inversion of IRO data. In this paper, the error characteristics are discussed and a new IRO retrieval method is developed, which uses electron density gradient information of reconstructed ancillary model derived from classic Abel inversion to correct Total Electron Content (TEC) and then combines the corrected TEC with the spherical symmetric Abel inversion method. The inversion results from the simulated data of the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) IRO are compared with reference profiles by directly interpolation, and show that the new retrieval method is more effective. [ABSTRACT FROM AUTHOR]

Large Forbush decrease (FD) events are analysed using data recorded by the ground-based Nagoya multi-directional muon telescope in Japan. As a part of the analysis we introduce a phase diagram for the channels of telescope, which provides more robust information about characteristics of events. Specifically, the slope of the regression line in the phase diagram represents the FD amplitude which can be computed for different channels. This allows us to analyze the dependence of the FD amplitude on the rigidity of CR particles. Two models for this dependence are considered, a power law and exponential and the former is found to be more suitable for the considered events. In terms of the power-law index and the FD amplitude the events are split into two groups. It is shown that the larger events are characterized by smaller power-law index than the smaller ones. [ABSTRACT FROM AUTHOR]

Comparing a galaxy's structure across multiple wavebands may require high spatial resolution. For example, determining the color gradient across a spiral arm may allow us to ascertain the co-rotation radius, which can in turn inform theoretical considerations on arm formation and evolution. However, pixels in the Sloan Digital Sky Survey are not precisely aligned across wavebands, making unbiased pixel-resolution comparisons difficult. Since foreground stars are effectively point sources, their location can be determined to sub-pixel precision by fitting their light profiles to an appropriate point spread function. Here we describe a completely automated method that uses foreground stars in the Sloan Digital Sky Survey to align images of galaxies across wavebands to about 0.02 pixels. We have applied the method to the approximately 900,000 galaxies collected from the Galaxy Zoo 1 project. The technique is not specific to the Sloan Digital Sky Survey and could be easily adaptable to other surveys, provided they only require translation for alignment. We have made all source code and aligned images publicly available. [ABSTRACT FROM AUTHOR]

Modern astronomical potentials modelling galaxies or stellar systems can be rather involved, and deriving their first derivatives (accelerations) and second derivatives (variational equations) in order to compute orbits and their chaoticity may be a formidable task. We present here a fully automated routine, dubbed Smart , with which the accelerations and the variational equations of an arbitrary potential that has been written in the Fortran 77 language can be computed. Almost any Fortran 77 statement is admitted in the potential, and the output are standard Fortran 77 routines ready to use. We validate our algorithm with a set of potentials including time-dependent, velocity-dependent and very complex potentials that even involve auxiliary routines. We also describe with some detail a realistic seven-component Galactic potential, MilkyWayHydra , which yields very involved derivatives, thus being a good test bed for Smart. [ABSTRACT FROM AUTHOR]

In this paper we present a reconstruction of the stratigraphic setting of the continental sedimentary sequences that were deposited by the Paleo-Tiber River within the greater area of Rome between 0.9 and 0.6 Ma, carried out through analyses of a large number of borehole data. Through palinspastic restoration of several cross sections we depict the original geometry of the sedimentary record that has been dislocated by intense tectonic activity linked to volcanism, and we reconstruct the geologic and paleogeographic evolution of this area. Moreover, we provide a complete review of the chronostratigraphic and magnetostratigraphic data reported in previous work, and we extend paleomagnetic analyses to three new clay sections. These geochronological constraints allow us to compare aggradation of the Paleo-Tiber sedimentary successions with the δ18O record, evidencing a strict link between sedimentation and sea-level changes in the Rome area. By doing so, we provide a direct test on the timing of the sea-level rise for MIS 19 through MIS 15: a record of data for which no equivalent exists in the literature. [ABSTRACT FROM AUTHOR]

Abstract: Given the fact that the back of the digital lunar model is invisible from any viewpoint, a view-dependent progressive transmission and rendering method for lunar model is proposed and a client-server browsing system is implemented. On the server side, the semi-regular lunar surface is partitioned into dozens of segments, and each segment is compressed independently using bicubic subdivision-surface wavelet and SPIHT. For any viewpoint, only the data of the visible segments are transmitted to the client side progressively, then decoded and locally reconstructed there. This approach not only improves the efficiency of transmission, but also reduces the reconstruction time greatly. We can browse the lunar model on the client almost in realtime. [Copyright &y& Elsevier]

This paper gives an overview of significant issues in the philosophy of cosmology, starting off by emphasizing the uniqueness of the universe and the way models are used in description and explanation. It then considers, basic limits on observations; the need to test alternatives; ways to test consistency; and implications of the uniqueness of the universe as regards distinguishing laws of physics from contingent conditions. It goes on to look at the idea of a multiverse as a scientific explanation of facts about fine-tuning, in particular considering criteria for a scientific theory and for justifying unseen entities. It considers the relation between physical laws and the natures of existence, and emphasizes limits on our knowledge of the physics relevant to the early universe (the physics horizon), and the non-physical nature of some claimed infinities. The final section looks briefly at deeper issues, commenting on the scope of enquiry of cosmological theory and the limits of science in relation to the creation of the universe. [ABSTRACT FROM AUTHOR]

Abstract: The growing scale and complexity of cataloguing and analyzing of astronomical data forces scientists to look for a new technologies and tools. The workflow environments seem best suited for their needs, but in practice they proved to be too complicated for most users. Before such environments are used commonly, they have to be properly adapted for specific needs of the scientific domain. To that end, we have created a universal solution based on the Kepler workflow environment. It consists of a library of domain modules, ready-to-use workflows and additional services for sharing and running workflows. There are three access levels depending on the needs and skills of the user: 1) desktop application, 2) web application 3) on-demand Virtual Research Environment. The whole solution is set up in the context of Polish Grid Infrastructure, enabling access to its resources. For flexibility it includes interoperability mechanisms with the domain specific applications and services (including astronomical Virtual Observatory) as well as with other domain grid services. [Copyright &y& Elsevier]

Highlights: [•] We confirmed the existence of line flux variations for IP Peg & DW UMa in the UV. [•] The variations of line fluxes are attributed to the variations of both density and temperature. [•] The line fluxes of IP Peg are greater than the line fluxes of DW UMa. [•] These variations can be explained by a white dwarf model atmospheres. [•] Conversion to absorption lines in an unusual low state occurs for DW UMa. [Copyright &y& Elsevier]

Highlights: [•] Modeling radial velocity (RV) curves helps explain contributing factors. [•] Factors include eccentricity, inclination angle, disk-tilt, and bright spots. [•] Fitting outlying data points can lead to a more accurate portrait of the system. [•] Gas stream overflow can also influence radial velocity curves. [•] We model and inspect RV curves of CV SW Sextanis and SU UMa dwarf novae systems. [ABSTRACT FROM AUTHOR]

Highlights: [•] Simple radiation emission model is used to extrapolate the MWL spectra of Blazars to VHE energies. [•] The intrinsic and the observed VHE spectra are used to estimate the optical depth at various redshifts. [•] The estimated optical depth values are then compared with the one predicted from different EBL models. [•] A systematic deviation of optical depth for z=0.116 and 0.536 is observed for Finke et al. (2010) EBL model. [ABSTRACT FROM AUTHOR]

Highlights: [•] We present the first near-UV light curve of HAT-P-16b. [•] The magnetic field of HAT-P-16b has been constrained. [•] ExoDRPL, Exoplanet Automated Data Reduction pipeline, was developed. [•] EXOMOP, Exoplanet Modeling Package, was also developed for this project. [ABSTRACT FROM AUTHOR]

Highlights: [•] Modeling of XX Cep shows that the secondary component fills its Roche lobe. [•] Study of the O−C diagram indicates the existence of a third and fourth body. [•] We obtained 0.031days pulsation period due to the primary star. [•] We confirm that XX Cep is quadruple system with a pulsation component. [ABSTRACT FROM AUTHOR]

Highlights: [•] We model new BVR light curves. [•] We detected a periodicity in the curve and provided two possible mechanisms. [•] The secular period increase may result from mass transfer. [•] We proposed the possible evolutionary statue. [Copyright &y& Elsevier]

Highlights: [•] We model the fundamental limits of detection in the 0.1–10THz range. [•] We target the detection of high redshift dusty galaxies as a specific case. [•] We include noise from atmospheric, extraterrestrial and optical emissions. [•] We model various ground based, airborne and space based systems. [•] Large-aperture and cryogenic balloon-borne telescopes are also explored. [Copyright &y& Elsevier]

Abstract: We present a framework for nonlinearly coupled scalar–tensor theory of gravity to address both inflation and core-collapse supernova problems. The unified approach is based on a novel dynamical trapping and relaxation of scalar gravity in highly energetic regimes. The new model provides a viable alternative mechanism of inflation free from various issues known to affect previous proposals. Furthermore, it could be related to observable violent astronomical events, specifically by releasing a significant amount of additional gravitational energy during core-collapse supernovae. A recent experiment at CERN relevant for testing this new model is briefly outlined. [Copyright &y& Elsevier]

Abstract: The dark matter halo mass function (HMF) is a characteristic property of cosmological structure formation models, quantifying the number density of dark matter haloes per unit mass in the Universe. A key goal of current and planned large galaxy surveys is to measure the HMF and to use it to test theories of dark matter and dark energy. We present a new web application for calculating the HMF—the frontend HMFcalc and the engine hmf. HMFcalc has been designed to be flexible, efficient and easy to use, providing observational and theoretical astronomers alike with the means to explore standard functional forms of the HMF or to tailor their own. We outline the theoretical background needed to compute the HMF, we show how it has been implemented in hmf, and finally we provide worked examples that illustrate HMFcalc’s versatility as an analysis tool. [Copyright &y& Elsevier]

Abstract: Weighted mean and median statistics techniques are used to combine 23 independent lower redshift, , Hubble parameter, , measurements and determine binned forms of . When these are combined with 5 higher redshift, , measurements the resulting constraints on cosmological parameters, of three cosmological models, that follow from the weighted-mean binned data are almost identical to those derived from analyses using the 28 independent measurements. This is consistent with what is expected if the lower redshift measurements errors are Gaussian. Plots of the binned weighted-mean versus z data are consistent with the presence of a cosmological deceleration–acceleration transition at redshift [30], which is expected in cosmological models with present-epoch energy budget dominated by dark energy as in the standard spatially-flat cosmological model. [Copyright &y& Elsevier]

Abstract: A stochastic gravitational-wave background (SGWB) is expected to arise from the superposition of many independent and unresolved gravitational-wave signals, of either cosmological or astrophysical origin. Some cosmological models (characterized, for instance, by a pseudo-scalar inflaton, or by some modification of gravity) break parity, leading to a polarized isotropic SGWB. We present the first upper limit on this parity violation from direct gravitational-wave measurements by measuring polarization of the SGWB in recent LIGO data and by assuming a generic power-law SGWB spectrum across the LIGO-sensitive frequency region. We also estimate sensitivity to parity violation for future generations of gravitational-wave detectors, both for a power-law spectrum and for a specific model of axion inflation. Since astrophysical sources are not expected to produce a polarized SGWB, measurements of polarization in the SGWB would provide a new way of differentiating between the cosmological and astrophysical SGWB sources. [Copyright &y& Elsevier]

Abstract: The cosmon field responsible for dynamical dark energy can induce an inflationary period in early cosmology. Details depend on dilatation symmetry breaking terms in its potential and kinetic term that are relevant only during early stages of the evolution of the universe. For a large range of parameters we find realistic primordial density fluctuations. As a particular example we discuss a model with almost static geometry in the Jordan frame for all epochs of cosmology. Here the cosmic evolution of the Hubble parameter is replaced by a variation of the Planck mass and particle masses. This model predicts a spectral index and a ratio for tensor to scalar fluctuations . [Copyright &y& Elsevier]

Abstract: In this article the D-criteria, which can be used to determine the genetic relationships of small bodies with their parent bodies in the solar system, are estimated. Drummond (1981), Southworth and Hawkins (1963), Jopek (1993), dynamic (Kalinin and Kulikova, 2007; Holshevnikov and Titov, 2007) D-criteria were analysed. It was found that the Drummond criterion is less sensitive to errors of observations and its upper limit does not exceed 0.2. The Southworth–Hawkins and Jopek D-criteria are more stable and have good convergence. Limiting values, which vary in the range of 0.3–0.6 (except for the Lyrids), were determined on the basis of the analysis of six meteor showers for the Southworth–Hawkins and Jopek criteria. [Copyright &y& Elsevier]

Abstract: The first complete Early Turonian–Early Campanian lacustrine succession has been recovered from the SK-I south (SK-Is) borehole in the Songliao Basin (SLB), northeastern China. We conducted a detailed cyclostratigraphic study of natural gamma-ray (GR) log, thorium (Th) log, and magnetic susceptibility (MS) data from this core. Spectral analysis of the upper Quantou Formation (K2q3+4), Qingshankou Formation (K2qn), Yaojia Formation (K2y), and lower Nenjiang Formation (K2n1+2) reveals a hierarchy of meter- to decameter-scale cycling in the data. The wavelength ratios of the cycles in these stratigraphic units are ~20:5:2:1, corresponding with those of Milankovitch cycle periods of 405kyr (long eccentricity):100kyr (short eccentricity):37kyr (obliquity):20kyr (precession), indicating astronomical control on sedimentation. An astronomical time scale (ATS) was established by tuning interpreted 405kyr cycles to a 405kyr orbital eccentricity target curve, and to four SIMS U–Pb zircon radioisotope ages. This ‘absolute’ ATS provides precise numerical ages for stratigraphic boundaries, biozones, geological and geophysical events, and serves as a basis for correlation of strata and events between marine and terrestrial systems. The ages of the C33r/C34n geomagnetic polarity boundary in K2n2 and three short reversal events in K2y are estimated as 83.633Ma, 84.819–84.862Ma, 84.982–85.092Ma and 85.240–85.629Ma, respectively. Long-period amplitude modulations in the obliquity and eccentricity bands of the 405-kyr-tuned GR-Th series provide strong evidence that long-period orbital forcing influenced climate change and depositional processes in the SLB. The extracted amplitude modulations provide evidence that the orbits of Earth and Mars were not in secular resonance, and were undergoing chaotic interactions during this time, although the modulations do not match those of recent astronomical models. [Copyright &y& Elsevier]

Abstract: We summarize the science opportunity, design elements, current and projected partner observatories, and anticipated science returns of the Astrophysical Multimessenger Observatory Network (AMON). AMON will link multiple current and future high-energy, multimessenger, and follow-up observatories together into a single network, enabling near real-time coincidence searches for multimessenger astrophysical transients and their electromagnetic counterparts. Candidate and high-confidence multimessenger transient events will be identified, characterized, and distributed as AMON alerts within the network and to interested external observers, leading to follow-up observations across the electromagnetic spectrum. In this way, AMON aims to evoke the discovery of multimessenger transients from within observatory subthreshold data streams and facilitate the exploitation of these transients for purposes of astronomy and fundamental physics. As a central hub of global multimessenger science, AMON will also enable cross-collaboration analyses of archival datasets in search of rare or exotic astrophysical phenomena. [Copyright &y& Elsevier]

Abstract: The number of interventions used in the field of autism is astronomical. Unfortunately, while there are effective and well-researched methods, many of the techniques that parents use have no empirical support. These interventions are expensive, take up valuable time, and in some cases are dangerous. How bad is this problem, how did the field get here, and what are potential solutions? This review covers this important but infrequently discussed topic. [Copyright &y& Elsevier]