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On October 4, 1957, Homo sapiens crossed a new threshold of technological innovation after constructing an artifact capable of entering Low Earth Orbit and effectively paving the way for a future of space exploration. This artifact was Sputnik 1, launched by the Soviet space program which triggered the "space race" of the mid‐20th century. Over the past 65 years, we have continued to explore and populate our solar system with rockets and spacecraft including satellites, probes, landers, and rovers. This expansion into our solar system has left traces of our presence on several planets including the Earth, Mars, Mercury, and Venus along with Earth's Moon, Titan, and several galaxy travelers in the form of asteroids and comets. Today, we have entered the realm of a new privatized and global space race, effectively a "new space race" or "new Space Age." As we expand our material footprint into new extraterrestrial environments, there is a growing need to understand the types of unique site formation processes capable of altering, destroying, or preserving this rapidly increasing archaeological record known as space heritage. Such understandings are germane to the subdiscipline of geoarchaeology, that part of archaeology dedicated to studying the interaction between humans, cultural heritage, and environmental systems from a geoscience perspective. Closely aligned and partially overlapping with the subdisciplines of space archaeology, archaeological science, and planetary geology, we introduce a new subfield we call planetary geoarchaeology to open discussion about how geoarchaeologists can play a role in addressing current and future issues surrounding the preservation and management of space heritage. To demonstrate the potential of the subdiscipline, we focus on the current archaeological record of the Moon, describe lunar site formation processes, and discuss the implications for the current and future preservation of space heritage in the lunar setting. Planetary geoarchaeology can be applied to practically every type of extraterrestrial environment, provided humans have left behind a measurable record. We hope this paper will spur more research studying human–environment interaction in space. [ABSTRACT FROM AUTHOR]

Space Archaeology (SA), also known as Satellite Archaeology, Satellite Remote Sensing for Archaeology, or Archaeology from Space, is part of the wider interdisciplinary field of Remote Sensing for Archaeology. The application of satellite data in archaeological investigations has proven useful for landscape observation and analysis, the detection of archaeological traces, the reconstruction and monitoring of natural and anthropic processes, and the management and promotion of archaeological heritage. During the last few decades, the increasing number of SA studies has demonstrated innovative growth in archaeological disciplines due to the significant enhancement of spatial technologies, the advancement of visual inspection and image processing techniques, the development of data fusion methodologies, and the improvement of multi-temporal analysis methods. Therefore, a broad overview of the current situation in the concepts and approaches of SA is necessary to gain greater awareness of the current potentialities and limitations of this science to better address future studies. The present work provides a review of the scientific literature by exploring the different aspects of SA and the goals achieved to date in three main application fields: Detection, monitoring, and promotion of archaeological heritage. The contributions reviewed were divided within each of these three categories by analyzing the type of SA data and methods applied. The results indicate that (1) most studies aim to detect archaeological sites compared to monitoring and promotion; (2) optical images are used more than SAR data; and (3) techniques of image enhancement and visual interpretation are applied more than other data processing methods. This brief overview allows us to consider SA as an evolving discipline, an engine for cross-skills training, as well as a promising future science that can play a key role in the frontier of sustainable development and the new space economy. [ABSTRACT FROM AUTHOR]

Space Archaeology (SA), also known as Satellite Archaeology, Satellite Remote Sensing for Archaeology, or Archaeology from Space, is part of the wider interdisciplinary field of Remote Sensing for Archaeology. The application of satellite data in archaeological investigations has proven useful for landscape observation and analysis, the detection of archaeological traces, the reconstruction and monitoring of natural and anthropic processes, and the management and promotion of archaeological heritage. During the last few decades, the increasing number of SA studies has demonstrated innovative growth in archaeological disciplines due to the significant enhancement of spatial technologies, the advancement of visual inspection and image processing techniques, the development of data fusion methodologies, and the improvement of multi-temporal analysis methods. Therefore, a broad overview of the current situation in the concepts and approaches of SA is necessary to gain greater awareness of the current potentialities and limitations of this science to better address future studies. The present work provides a review of the scientific literature by exploring the different aspects of SA and the goals achieved to date in three main application fields: Detection, monitoring, and promotion of archaeological heritage. The contributions reviewed were divided within each of these three categories by analyzing the type of SA data and methods applied. The results indicate that (1) most studies aim to detect archaeological sites compared to monitoring and promotion; (2) optical images are used more than SAR data; and (3) techniques of image enhancement and visual interpretation are applied more than other data processing methods. This brief overview allows us to consider SA as an evolving discipline, an engine for cross-skills training, as well as a promising future science that can play a key role in the frontier of sustainable development and the new space economy.

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The current environment in space appears to have many of the traits of a security dilemma. Left unchecked, security dilemmas create unstable conditions and generate suboptimal arms racing, potentially leading to war. The growing orbital security dilemma is being fueled by the common perception that space is an offense-dominant environment. This misperception of offense dominance is ruling out viable reassurance strategies and forcing states to pursue self-defeating policies that are only intensifying the security dilemma in space. This article addresses the more nuanced reality of the offense-defense balance in space and its implications for the future of great power competition in orbit. It concludes that states should pursue a hedging strategy that favors robust defensive capabilities and a disaggregated space architecture due to a combination of a nearly neutral offense-defense balance and the persistence of some form of the security dilemma driven by borderless orbital geography. [ABSTRACT FROM AUTHOR]

With the advent of the space missions CoRoT and Kepler, it has recently become feasible to determine precise asteroseismic masses and relative ages for large samples of red giant stars. We present the CoRoGEE dataset, obtained from CoRoT light curves for 606 red giants in two fields of the Galactic disc that have been co-observed by the Apache Point Observatory Galactic Evolution Experiment (APOGEE). We used the Bayesian parameter estimation code PARAM to calculate distances, extinctions, masses, and ages for these stars in a homogeneous analysis, resulting in relative statistical uncertainties of .2% in distance, ~4% in radius, ~9% in mass and ~25% in age. We also assessed systematic age uncertainties stemming from different input physics and mass loss. We discuss the correlation between ages and chemical abundance patterns of field stars over a broad radial range of the Milky Way disc (5 kpc < RGal < 14 kpc), focussing on the [ /Fe]-[Fe/H]-age plane in five radial bins of the Galactic disc. We find an overall agreement with the expectations of pure chemical-evolution models computed before the present data were available, especially for the outer regions. However, our data also indicate that a significant fraction of stars now observed near and beyond the solar neighbourhood migrated from inner regions. Mock CoRoGEE observations of a chemodynamical Milky Way disc model indicate that the number of high-metallicity stars in the outer disc is too high to be accounted for even by the strong radial mixing present in the model. The mock observations also show that the age distribution of the [ /Fe]-enhanced sequence in the CoRoGEE inner-disc field is much broader than expected from a combination of radial mixing and observational errors. We suggest that a thick-disc/bulge component that formed stars for more than 3 Gyr may account for these discrepancies. Our results are subject to future improvements due to (a) the still low statistics, because our sample had to be sliced into bins of Galactocentric distances and ages; (b) large uncertainties in proper motions (and therefore guiding radii); and (c) corrections to the asteroseismic mass-scaling relation. The situation will improve not only upon the upcoming Gaia data releases, but also with the foreseen increase in the number of stars with both seismic and spectroscopic information. [ABSTRACT FROM AUTHOR]

Copyright of Archaeologies is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents information related to the solar analemma, formed by the combined effects of the Earth's variation in speed along its elliptical orbit around the Sun and its tilted axis of rotation. It is mentioned that the equation of time, which describes the difference between sundial time is graphically represented by the analemma curve.

The main goal of Galactic Archaeology is to understand the formation and evolution of the basic Galactic components. This requires sophisticated chemo-dynamical modeling, where disk asymmetries (e.g., perturbations from the bar, spirals, and mergers) and nonequilibrium processes are taken into account self-consistently. Here we discuss the current status of Galactic chemo-dynamical modeling and focus on a recent hybrid technique, which helps circumvent traditional problems with chemical enrichment and star formation encountered in fully self-consistent cosmological simulations. We show that this model can account for a number of chemo-kinematic relations in the Milky Way, as discussed in previous works. In addition, we demonstrate that our model matches well the observed age-[c*/Fe] relation and that blurring may be insufficient to explain the scatter in the age-metallicity relation. [ABSTRACT FROM AUTHOR]

Galactic Archaeology has recently been challenged by the fact that stars observed now in a certain location are not necessarily born there, but could have been kicked out from their birth places by different internal and/or external processes. We have made one of the first attempts to quantify how important stellar mixing could be in the case of our Galaxy, and how much of the original chemodynamical correlations would have been destroyed by such processes. Our unique approach has allowed us to conclude that although stellar mixing does take place in our Galaxy, many of the main relations between chemistry and age suggested by pure chemical evolution models are still generally valid. However, stringent constraints can be obtained only when stellar ages will be known for a large number of field stars. This is certainly one of the goals of Gaia, but in the meantime it has been shown that Asteroseismology can also provide a way to estimate ages of giants, even at large distances from the Sun. Here we present the first results obtained with a sample of CoRoT stars that have APOGEE spectra, in the framework of the CoRoGEE collaboration. The results coming from this still very recent approach (he. asteroseismology of Galactic populations) reveals that we might be on the right track in terms of quantifying radial mixing, but these results also suggest the chemical enrichment of the Galactic disk(s) to have been more complex than previously envisaged. Intriguingly, we find that the use of [a/Fe]-ratios as proxy for age, although generally valid, breaks down for some stars. [ABSTRACT FROM AUTHOR]

The article presents a reflection on the archaeology of the rural world in France and proposes to study the manuring process in the larger context of soil conditioning and its potential material correlates. Evidence is given proving the use of manure since Antiquity. The incorporation of domestic waste in the manuring is discussed, and the question of its leading to the discovering of pottery shards is addressed. The different types of soil-enriching agents used in the Middle Ages in Europe are mentioned.

Aeolian dune fields have been described on Earth, Mars, Venus, and Titan. The amount and fidelity of data being returned from orbiting spacecraft and landers have enabled a new era in aeolian studies. This progress report presents an overview of the latest planetary geomorphic studies characterizing aeolian processes on extraterrestrial surfaces. Our understanding of aeolian processes on other planetary surfaces comes largely from Earth analog studies, along with wind tunnel experiments and theoretical modeling. However, an important difference is that unlike terrestrial dunes most dunes on Venus and Mars are composed primarily of basaltic particles. Additional research is needed to understand how basaltic particles weather both physically and chemically so that it will be possible to apply traditional sedimentological concepts, such as sediment maturity, to understanding aeolian processes on Venus and Mars. It may also be possible to characterize sediment maturity and provenance through remote sensing data once we have a better understanding of basaltic sediments. Although there have been a variety of dune forms identified on the surfaces of the other terrestrial planets, the only dune form found on all of them is linear dunes. Even though linear dunes are the most common dune forms on Earth, we currently have a poor understanding as to how they are formed, and additional work is needed to understand these features. [ABSTRACT FROM AUTHOR]

This work presents the preliminary thermal behavior, in transient condition, of the ITASAT satellite (an experimental satellite developed by Technological Institute of Aeronautics - ITA). The flight critical cases and some parametric analysis were evaluated. ITASAT will be the first Brazilian duty satellite developed by universities and its main function will be data relay. This program is being directed by ITA with collaboration of others Brazilian universities. National Institute of Space Researches (INPE) supports technically and the Brazilian Space Agency (AEB) sponsors the program. The thermal analyzer SINDA/FLUINT has been used as computational platform. Parameters such as orbit type and attitude of the satellite influence directly the intensity of the external heat loads. Associating these loads with the equipment's dissipation is possible to calculate the temperature distribution in the satellite. This study is part of the thermal control project that will guarantee that the high and low acceptable temperature limits for all equipment can be obtained. The presented results are physically coherent for Low Earth Orbit satellites. [ABSTRACT FROM AUTHOR]

Copyright of Archaeologies is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The article presents information related to Pulsating Red Giants (PRG). It is mentioned that radial pulsation begins when the spectral type is mid-K as the star expands and cools. It is stated that about a third of all PRGs have a long secondary period while many PRGs pulsate in two or more modes at the same time.

This third supplement to the RASC Catalogue of meteorites records the addition of specimens of twelve different meteorites, four different impactites, and one associated object. [ABSTRACT FROM AUTHOR]