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  Subjects -> AERONAUTICS AND SPACE FLIGHT (Total: 120 journals)
Showing 1 - 30 of 30 Journals sorted alphabetically
Acta Astronautica     Hybrid Journal   (Followers: 485)
Advances in Aerospace Engineering     Open Access   (Followers: 67)
Advances in Aerospace Science and Technology     Open Access   (Followers: 7)
Advances in Astronautics Science and Technology     Hybrid Journal  
Advances in Space Research     Full-text available via subscription   (Followers: 455)
Aeronautical Journal, The     Hybrid Journal   (Followers: 11)
Aerospace     Open Access   (Followers: 58)
Aerospace Medicine and Human Performance     Full-text available via subscription   (Followers: 15)
Aerospace Science and Technology     Hybrid Journal   (Followers: 424)
Aerospace Scientific Journal     Open Access   (Followers: 16)
Aerospace Systems     Hybrid Journal   (Followers: 3)
Aerospace technic and technology     Open Access   (Followers: 2)
Aerotecnica Missili & Spazio : Journal of Aerospace Science, Technologies & Systems     Hybrid Journal  
AIAA Journal     Hybrid Journal   (Followers: 1177)
Air Force Magazine     Full-text available via subscription   (Followers: 11)
Air Medical Journal     Hybrid Journal   (Followers: 8)
Annual of Navigation     Open Access   (Followers: 22)
Artificial Satellites     Open Access   (Followers: 23)
ASTRA Proceedings     Open Access   (Followers: 2)
Astrodynamics     Hybrid Journal   (Followers: 1)
Aviation     Open Access   (Followers: 15)
Aviation Advances & Maintenance     Open Access   (Followers: 3)
Aviation in Focus - Journal of Aeronautical Sciences     Open Access   (Followers: 10)
Aviation Psychology and Applied Human Factors     Hybrid Journal   (Followers: 27)
Aviation Week     Full-text available via subscription   (Followers: 438)
Canadian Aeronautics and Space Journal     Full-text available via subscription   (Followers: 33)
CEAS Aeronautical Journal     Hybrid Journal   (Followers: 29)
Chinese Journal of Aeronautics     Open Access   (Followers: 20)
Ciencia y Poder Aéreo     Open Access   (Followers: 2)
Civil Aviation High Technologies     Open Access   (Followers: 5)
Control Systems     Hybrid Journal   (Followers: 318)
Cosmic Research     Hybrid Journal   (Followers: 4)
COSPAR Colloquia Series     Full-text available via subscription   (Followers: 11)
Egyptian Journal of Remote Sensing and Space Science     Open Access   (Followers: 24)
Elsevier Astrodynamics Series     Full-text available via subscription   (Followers: 12)
Fatigue of Aircraft Structures     Open Access   (Followers: 15)
Frontiers in Astronomy and Space Sciences     Open Access   (Followers: 12)
Gyroscopy and Navigation     Hybrid Journal   (Followers: 256)
IEEE Aerospace and Electronic Systems Magazine     Full-text available via subscription   (Followers: 277)
IEEE Journal on Miniaturization for Air and Space Systems     Hybrid Journal   (Followers: 2)
IEEE Transactions on Aerospace and Electronic Systems     Hybrid Journal   (Followers: 384)
IEEE Transactions on Circuits and Systems I: Regular Papers     Hybrid Journal   (Followers: 39)
International Journal of Aeroacoustics     Hybrid Journal   (Followers: 39)
International Journal of Aerodynamics     Hybrid Journal   (Followers: 36)
International Journal of Aeronautical and Space Sciences     Hybrid Journal   (Followers: 2)
International Journal of Aerospace Engineering     Open Access   (Followers: 81)
International Journal of Aerospace Psychology     Hybrid Journal   (Followers: 23)
International Journal of Aerospace Sciences     Open Access   (Followers: 31)
International Journal of Applied Geospatial Research     Hybrid Journal   (Followers: 7)
International Journal of Aviation Management     Hybrid Journal   (Followers: 8)
International Journal of Aviation Technology, Engineering and Management     Full-text available via subscription   (Followers: 7)
International Journal of Aviation, Aeronautics, and Aerospace     Open Access   (Followers: 4)
International Journal of Crashworthiness     Hybrid Journal   (Followers: 12)
International Journal of Micro Air Vehicles     Full-text available via subscription   (Followers: 11)
International Journal of Satellite Communications Policy and Management     Hybrid Journal   (Followers: 13)
International Journal of Space Science and Engineering     Hybrid Journal   (Followers: 11)
International Journal of Space Structures     Full-text available via subscription   (Followers: 17)
International Journal of Space Technology Management and Innovation     Full-text available via subscription   (Followers: 10)
International Journal of Sustainable Aviation     Hybrid Journal   (Followers: 5)
International Journal of Turbo and Jet-Engines     Hybrid Journal   (Followers: 6)
Investigación Pecuaria     Open Access   (Followers: 3)
Journal of Aerodynamics     Open Access   (Followers: 17)
Journal of Aeronautical Materials     Open Access   (Followers: 9)
Journal of Aeronautics & Aerospace Engineering     Open Access   (Followers: 28)
Journal of Aerospace Engineering     Full-text available via subscription   (Followers: 68)
Journal of Aerospace Engineering & Technology     Full-text available via subscription   (Followers: 16)
Journal of Aerospace Information Systems     Hybrid Journal   (Followers: 20)
Journal of Aerospace Information Systems     Hybrid Journal   (Followers: 32)
Journal of Aerospace Technology and Management     Open Access   (Followers: 7)
Journal of Aircraft     Hybrid Journal   (Followers: 339)
Journal of Aircraft and Spacecraft Technology     Open Access   (Followers: 8)
Journal of Airline and Airport Management     Open Access   (Followers: 12)
Journal of Astrobiology & Outreach     Open Access   (Followers: 3)
Journal of Aviation Technology and Engineering     Open Access   (Followers: 11)
Journal of Aviation/Aerospace Education & Research     Open Access   (Followers: 2)
Journal of Engineering and Technological Sciences     Open Access   (Followers: 1)
Journal of Guidance, Control, and Dynamics     Hybrid Journal   (Followers: 206)
Journal of KONBiN     Open Access   (Followers: 3)
Journal of Navigation     Hybrid Journal   (Followers: 280)
Journal of Propulsion and Power     Hybrid Journal   (Followers: 608)
Journal of Space Safety Engineering     Hybrid Journal   (Followers: 7)
Journal of Space Weather and Space Climate     Open Access   (Followers: 27)
Journal of Spacecraft and Rockets     Hybrid Journal   (Followers: 770)
Journal of Spatial Science     Hybrid Journal   (Followers: 3)
Journal of the American Helicopter Society     Full-text available via subscription   (Followers: 7)
Journal of the Astronautical Sciences     Hybrid Journal   (Followers: 8)
Journal of the Australasian Society of Aerospace Medicine     Open Access   (Followers: 1)
Journal of Wind Engineering and Industrial Aerodynamics     Hybrid Journal   (Followers: 16)
Life Sciences in Space Research     Hybrid Journal   (Followers: 3)
MAD - Magazine of Aviation Development     Open Access   (Followers: 2)
Mekanika : Jurnal Teknik Mesin i     Open Access   (Followers: 1)
Microgravity Science and Technology     Hybrid Journal   (Followers: 2)
New Space     Hybrid Journal   (Followers: 6)
Nonlinear Dynamics     Hybrid Journal   (Followers: 19)
npj Microgravity     Open Access   (Followers: 3)
Open Aerospace Engineering Journal     Open Access   (Followers: 1)
Population Space and Place     Hybrid Journal   (Followers: 9)
Problemy Mechatroniki. Uzbrojenie, lotnictwo, inżynieria bezpieczeństwa / Problems of Mechatronics. Armament, Aviation, Safety Engineering     Open Access   (Followers: 3)
Proceedings of the Human Factors and Ergonomics Society Annual Meeting     Hybrid Journal   (Followers: 16)
Proceedings of the Institution of Mechanical Engineers Part G: Journal of Aerospace Engineering     Hybrid Journal   (Followers: 45)
Progress in Aerospace Sciences     Full-text available via subscription   (Followers: 80)
Propulsion and Power Research     Open Access   (Followers: 67)
REACH - Reviews in Human Space Exploration     Full-text available via subscription   (Followers: 5)
Research & Reviews : Journal of Space Science & Technology     Full-text available via subscription   (Followers: 17)
RocketSTEM     Free   (Followers: 6)
Russian Aeronautics (Iz VUZ)     Hybrid Journal   (Followers: 24)
Science and Education : Scientific Publication of BMSTU     Open Access   (Followers: 1)
Space and Polity     Hybrid Journal   (Followers: 4)
Space Policy     Hybrid Journal   (Followers: 30)
Space Research Today     Full-text available via subscription   (Followers: 48)
Space Safety Magazine     Free   (Followers: 51)
Space Science International     Open Access   (Followers: 193)
Space Science Reviews     Hybrid Journal   (Followers: 97)
SpaceNews     Free   (Followers: 825)
Spatial Information Research     Hybrid Journal   (Followers: 1)
Technical Soaring     Full-text available via subscription   (Followers: 1)
Transport and Aerospace Engineering     Open Access   (Followers: 1)
Transportmetrica A : Transport Science     Hybrid Journal   (Followers: 8)
Unmanned Systems     Hybrid Journal   (Followers: 5)
Вісник Національного Авіаційного Університету     Open Access   (Followers: 2)

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Journal Cover
Frontiers in Astronomy and Space Sciences
Number of Followers: 12  

  This is an Open Access Journal Open Access journal
ISSN (Online) 2296-987X
Published by Frontiers Media Homepage  [86 journals]
  • Editorial: Presentations at the 4th Workshop of the German Astrobiological
           Society (DAbG) on Astrobiology, 26–27 September 2019, Vienna, Austria

    • Authors: Tetyana Milojevic, Rosa De La Torre Noetzel, Oliver Strbak, Dirk Schulze-Makuch
      PubDate: 2021-01-18T00:00:00Z
  • Testing and Validating Two Morphological Flare Predictors by Logistic
           Regression Machine Learning

    • Authors: M. B. Korsós, R. Erdélyi, J. Liu, H. Morgan
      Abstract: Whilst the most dynamic solar active regions (ARs) are known to flare frequently, predicting the occurrence of individual flares and their magnitude, is very much a developing field with strong potentials for machine learning applications. The present work is based on a method which is developed to define numerical measures of the mixed states of ARs with opposite polarities. The method yields compelling evidence for the assumed connection between the level of mixed states of a given AR and the level of the solar eruptive probability of this AR by employing two morphological parameters: 1) the separation parameter Sl−f and 2) the sum of the horizontal magnetic gradient GS. In this work, we study the efficiency of Sl−f and GS as flare predictors on a representative sample of ARs, based on the SOHO/MDI-Debrecen Data (SDD) and the SDO/HMI - Debrecen Data (HMIDD) sunspot catalogues. In particular, we investigate about 1,000 ARs in order to test and validate the joint prediction capabilities of the two morphological parameters by applying the logistic regression machine learning method. Here, we confirm that the two parameters with their threshold values are, when applied together, good complementary predictors. Furthermore, the prediction probability of these predictor parameters is given at least 70% a day before.
      PubDate: 2021-01-18T00:00:00Z
  • Anharmonic Vibrational Frequencies and Spectroscopic Constants for the
           Detection of Ethynol in Space

    • Authors: Jax D. Dallas, Brent R. Westbrook, Ryan C. Fortenberry
      Abstract: The ethynol (HCCOH) molecule has recently been shown to be present in simulated astrochemical ices possibly linking it to molecular building blocks for interstellar complex organic molecules like amino acids. The proposed reaction mechanism suggests the simultaneous formation of both ketene and ethynol from mixed carbon monoxide/water ice in simulated interstellar conditions. Rigorous anharmonic spectral data within both the IR and microwave regions are needed for possible detection of ethynol in the interstellar medium. This study provides the first such data for this molecule from high-level quantum chemical computations where experiment is currently lacking. Ethynol has a Beff comparable to, but distinct from acetonitrile at 9,652.1 MHz and three notable infrared features with two in the hydride stretching-regions and the C–C stretch at 2,212.8 cm−1. The ketene isomer has already been detected in the interstellar medium, and the possible detection of ethynol made possible by this work may lead to a deeper understanding of the proposed ice formation mechanism involving both species and how this relates to the molecular origins of life.
      PubDate: 2021-01-15T00:00:00Z
  • Significance of Cooling Effect on Comprehension of Kink Oscillations of
           Coronal Loops

    • Authors: Daria Shukhobodskaia, Alexander A. Shukhobodskiy, Chris J. Nelson, Michael S. Ruderman, Robert Erdélyi
      Abstract: Kink oscillations of coronal loops have been widely studied, both observationally and theoretically, over the past few decades. It has been shown that the majority of observed driven coronal loop oscillations appear to damp with either exponential or Gaussian profiles and a range of mechanisms have been proposed to account for this. However, some driven oscillations seem to evolve in manners which cannot be modeled with purely Gaussian or exponential profiles, with amplification of oscillations even being observed on occasions. Recent research has shown that incorporating the combined effects of coronal loop expansion, resonant absorption, and cooling can cause significant deviations from Gaussian and exponential profiles in damping profiles, potentially explaining increases in oscillation amplitude through time in some cases. In this article, we analyze 10 driven kink oscillations in coronal loops to further investigate the ability of expansion and cooling to explain complex damping profiles. Our results do not rely on fitting a periodicity to the oscillations meaning complexities in both temporal (period changes) and spatial (amplitude changes) can be accounted for in an elegant and simple way. Furthermore, this approach could also allow us to infer some important diagnostic information (such as, for example, the density ratio at the loop foot-points) from the oscillation profile alone, without detailed measurements of the loop and without complex numerical methods. Our results imply the existence of correlations between the density ratio at the loop foot-points and the amplitudes and periods of the oscillations. Finally, we compare our results to previous models, namely purely Gaussian and purely exponential damping profiles, through the calculation of χ2 values, finding the inclusion of cooling can produce better fits in some cases. The current study indicates that thermal evolution should be included in kink-mode oscillation models in the future to help us to better understand oscillations that are not purely Gaussian or exponential.
      PubDate: 2021-01-14T00:00:00Z
  • On the Variation of Intermittency of Fast and Slow Solar Wind With Radial
           Distance, Heliospheric Latitude, and Solar Cycle

    • Authors: Anna Wawrzaszek, Marius Echim
      Abstract: Intermittency, an important property of astrophysical plasma turbulence, is studied extensively during last decades from in-situ measurements of the solar wind plasma and magnetic field in the ecliptic plane and at higher latitudes, and heliocentric distances between 0.3 and 5 Astronomical Units. In this paper, we review the main findings on intermittency derived from investigation of solar wind turbulence for the inertial range of scales. It turns out that our current knowledge on the evolution of intermittency in the heliosphere is based on two missions, Helios two and Ulysses. We discuss the importance of data selection methodologies and applications for heliospheric spacecraft, the different data analysis techniques (the anomalous scaling of the structure function, the non-Gaussianity of the probability distribution functions, the local intermittency measure estimated from a wavelet representation and the multifractal spectrum). Studies show that Alvénic solar wind is less intermittent but reveals increase with the radial distance. Moreover, intermittency is stronger for the magnetic than for velocity fluctuations and is considered to be responsible for the increase with the radial distance of the anisotropy of magnetic fluctuations. The intermittency of fast solar wind at solar minimum decreases with latitude. Finally, the level of intermittency in the solar wind depends on solar cycle phase, reflecting the changes of the state of solar wind and suggesting that the deeper study of origin of fast and slow wind can further improve our understanding of the intermittency.
      PubDate: 2021-01-13T00:00:00Z
  • A Review of Studies of Geomagnetic Storms and Auroral/Magnetospheric
           Substorms Based on the Electric Current Approach

    • Authors: Syun-Ichi Akasofu
      Abstract: The progress of space physics is reviewed from my personal point of view, particularly how I have reached my present understanding of auroral substorms and geomagnetic storms from the time of the earliest days of space physics. This review is somewhat unique in two ways. First of all, instead of taking the magnetic field line approach (including magnetic reconnection), I have taken the electric current approach; it consists of power supply (dynamo), transmission (currents/circuits), and dissipation (auroral/magnetospheric substorms). This is the basic way to study electromagnetic phenomena and it is much more instructive in understanding the physics involved in the chain processes. Secondly, this is not a textbook-like review, but it is hoped that my humble experience may be useful to see how a new science of space physics has evolved with a number of controversies. On the other hand, it can be seen that the electric current approach is still in a very rudiment stage. Thus, new generations of researchers are most welcome in taking this new way of studying auroral/magnetospheric substorms and geomagnetic storms.
      PubDate: 2021-01-08T00:00:00Z
  • Radio Measurements of the Magnetic Field in the Solar Chromosphere and the

    • Authors: Costas E. Alissandrakis, Dale E. Gary
      Abstract: The structure of the upper solar atmosphere, on all observable scales, is intimately governed by the magnetic field. The same holds for a variety of solar phenomena that constitute solar activity, from tiny transient brightening to huge Coronal Mass Ejections. Due to inherent difficulties in measuring magnetic field effects on atoms (Zeeman and Hanle effects) in the corona, radio methods sensitive to electrons are of primary importance in obtaining quantitative information about its magnetic field. In this review we explore these methods and point out their advantages and limitations. After a brief presentation of the magneto-ionic theory of wave propagation in cold, collisionless plasmas, we discuss how the magnetic field affects the radio emission produced by incoherent emission mechanisms (free-free, gyroresonance, and gyrosynchrotron processes) and give examples of measurements of magnetic filed parameters in the quiet sun, active regions and radio CMEs. We proceed by discussing how the inversion of the sense of circular polarization can be used to measure the field above active regions. Subsequently we pass to coherent emission mechanisms and present results of measurements from fiber bursts, zebra patterns, and type II burst emission. We close this review with a discussion of the variation of the magnetic field, deduced by radio measurements, from the low corona up to ~ 10 solar radii and with some thoughts about future work.
      PubDate: 2021-01-06T00:00:00Z
  • Variability of Gravity Wave Effects on the Zonal Mean Circulation and
           Migrating Terdiurnal Tide as Studied With the Middle and Upper Atmosphere
           Model (MUAM2019) Using a Nonlinear Gravity Wave Scheme

    • Authors: Friederike Lilienthal, Erdal Yiğit, Nadja Samtleben, Christoph Jacobi
      Abstract: Implementing a nonlinear gravity wave (GW) parameterization into a mechanistic middle and upper atmosphere model, which extends to the lower thermosphere (160 km), we study the response of the atmosphere in terms of the circulation patterns, temperature distribution, and migrating terdiurnal solar tide activity to the upward propagating small-scale internal GWs originating in the lower atmosphere. We perform three test simulations for the Northern Hemisphere winter conditions in order to assess the effects of variations in the initial GW spectrum on the climatology and tidal patterns of the mesosphere and lower thermosphere. We find that the overall strength of the source level momentum flux has a relatively small impact on the zonal mean climatology. The tails of the GW source level spectrum, however, are crucial for the lower thermosphere climatology. With respect to the terdiurnal tide, we find a strong dependence of tidal amplitude on the induced GW drag, generally being larger when GW drag is increased.
      PubDate: 2020-12-17T00:00:00Z
  • Relationship Between Geomagnetic Storms and Auroral/Magnetospheric
           Substorms: Early Studies

    • Authors: Syun-Ichi Akasofu
      Abstract: This paper describes a short story of how I learned in early days in space physics (1960–1970) that there are the direct and feed-back relationships between geomagnetic storms and auroral/magnetospheric substorms. In those days, both geomagnetic storms and auroral substorms were almost independent subjects. It is now understood that auroral substorms are directly related to the development of the ring current and thus of the main phase of geomagnetic storms. Further, we have begun to recognize that the growth of the ring current (caused by auroral/magnetospheric substorms) will change the internal structure of the magnetosphere, which in turn will change and could modify at least the intensity of auroral substorms. Thus, there are interesting feed-back processes between them. It is expected that this feed-back relationship between geomagnetic storms and auroral/magnetospheric substorms will become one of the major issues in magnetospheric physics in the future. In fact, an effort to understand this relationship will deepen our understanding of both geomagnetic storms and auroral/magnetospheric substorms. The progress in understanding the relationship between auroral substorms and geomagnetic storms is an example, in which it takes a long time to advance even one step. It is hoped that this paper will serve to learn the background in the development of space physics in the early days.
      PubDate: 2020-12-09T00:00:00Z
  • Magnetic Field Turbulence in the Solar Wind at Sub‐ion Scales: In Situ
           Observations and Numerical Simulations

    • Authors: L. Matteini, L. Franci, O. Alexandrova, C. Lacombe, S. Landi, P. Hellinger, E. Papini, A. Verdini
      Abstract: We investigate the transition of the solar wind turbulent cascade from MHD to sub‐ion range by means of a detailed comparison between in situ observations and hybrid numerical simulations. In particular, we focus on the properties of the magnetic field and its component anisotropy in Cluster measurements and hybrid 2D simulations. First, we address the angular distribution of wave vector in the kinetic range between ion and electron scales by studying the variance anisotropy of the magnetic field components. When taking into account a single-direction sampling, like that performed by spacecraft in the solar wind, the main properties of the fluctuations observed in situ are also recovered in our numerical description. This result confirms that solar wind turbulence in the sub‐ion range is characterized by a quasi-2D gyrotropic distribution of k-vectors around the mean field. We then consider the magnetic compressibility associated with the turbulent cascade and its evolution from large-MHD to sub‐ion scales. The ratio of field aligned to perpendicular fluctuations, typically low in the MHD inertial range, increases significantly when crossing ion scales and its value in the sub‐ion range is a function of the total plasma beta only, as expected from theoretical predictions, with higher magnetic compressibility for higher beta. Moreover, we observe that this increase has a gradual trend from low to high beta values in the in situ data; this behavior is well captured by the numerical simulations. The level of magnetic field compressibility that is observed in situ and in the simulations is in fairly good agreement with theoretical predictions, especially at high beta, suggesting that, in the kinetic range explored, the turbulence is supported by low-frequency and highly oblique fluctuations in pressure balance, like kinetic Alfvén waves or other slowly evolving coherent structures. The resulting scaling properties as a function of the plasma beta and the main differences between numerical and theoretical expectations and in situ observations are also discussed.
      PubDate: 2020-12-08T00:00:00Z
  • Iterative Tomography: A Key to Providing Time-Dependent 3-D
           Reconstructions of the Inner Heliosphere and the Unification of Space
           Weather Forecasting Techniques

    • Authors: Bernard V. Jackson, Andrew Buffington, Lucas Cota, Dusan Odstrcil, Mario M. Bisi, Richard Fallows, Munetoshi Tokumaru
      Abstract: Over several decades, UCSD has developed and continually updated a time-dependent iterative three-dimensional (3-D) reconstruction technique to provide global heliospheric parameters—density, velocity, and component magnetic fields. For expediency, this has used a kinematic model as a kernel to provide a fit to either interplanetary scintillation (IPS) or Thomson-scattering observations. This technique has been used in near real time over this period, employing Institute for Space-Earth Environmental Research, Japan, IPS data to predict the propagation of these parameters throughout the inner heliosphere. We have extended the 3-D reconstruction analysis to include other IPS Stations around the Globe in a Worldwide Interplanetary Scintillation Stations Network. In addition, we also plan to resurrect the Solar Mass Ejection Imager Thomson-scattering analysis as a basis for 3-D analysis to be used by the latest NASA Small Explorer heliospheric imagers of the Polarimeter to Unify the Corona and Heliosphere mission, the All Sky Heliospheric Imager, and other modern wide-field imagers. Better data require improved heliospheric modeling that incorporates non-radial transport of heliospheric flows, and shock processes. Looking ahead to this, we have constructed an interface between the 3-D reconstruction tomography and 3-D MHD models and currently include the ENLIL model as a kernel in the reconstructions to provide this fit. In short, we are now poized to provide all of these innovations in a next step: to include them for planned ground-based and spacecraft instruments, all to be combined into a truly global 3-D heliospheric system which utilizes these aspects in their data and modeling.
      PubDate: 2020-11-25T00:00:00Z
  • Detection of Microorganisms in Low-Temperature Water Environments by in
           situ Generation of Biogenic Nanoparticles

    • Authors: Dmitry A. Skladnev, Lina V. Vasilyeva, Yulia Yu. Berestovskaya, Oleg R. Kotsyurbenko, Sergei V. Kalenov, Vladimir V. Sorokin
      Abstract: A new nanobiotechnological approach for the detection of extraterrestrial Earth-like biological forms is proposed. The approach is based on the ability of microbial cells to reduce artificially added cations with the generation of crystalline nanoparticles (NPs) from zero-valent atoms. The method is named DBNG (Detection of Biogenic Nanoparticles Generation). The subglacial low-temperature oligotrophic Lake Untersee in Antarctica was used as a model of putative extraterrestrial water environments inhabited by Earth-like type microorganisms. The DBNG protocol for the comparative study of microbial communities of low-temperature oligotrophic environments was optimized on the base of experiments with the pure culture of psychroactive bacterium Cryobacterium sp. 1639 isolated earlier from Lake Untersee. The formation of silver nanoparticles (Ag°NPs) has been conducted in natural water samples of three horizons at low temperature (+5°C), which was in the temperature range registered in the Lake Untersee. The generation of biogenic Ag°NPs was detected only at the presence of indigenous microorganisms in all studied samples. No Ag°NPs generation was observed in the lake water samples artificially free of cells or exposed to pasteurization (two types of controls). The miniature microfluidic chip for an automated version of the device, based on using different analytical methods for recording in situ-formed biogenic nanoparticles, is proposed. The device allows the detection of the biological objects directly at the sampling site.
      PubDate: 2020-11-23T00:00:00Z
  • A Comparison Study of Extrapolation Models and Empirical Relations in
           Forecasting Solar Wind

    • Authors: Sandeep Kumar, Arghyadeep Paul, Bhargav Vaidya
      Abstract: Coronal mass ejections and high speed solar streams serve as perturbations to the background solar wind that have major implications in space weather dynamics. Therefore, a robust framework for accurate predictions of the background wind properties is a fundamental step toward the development of any space weather prediction toolbox. In this pilot study, we focus on the implementation and comparison of various models that are critical for a steady state, solar wind forecasting framework. Specifically, we perform case studies on Carrington rotations 2,053, 2,082, and 2,104, and compare the performance of magnetic field extrapolation models in conjunction with velocity empirical formulations to predict solar wind properties at Lagrangian point L1. Two different models to extrapolate the solar wind from the coronal domain to the inner-heliospheric domain are presented, namely, a) Kinematics based [Heliospheric Upwind eXtrapolation (HUX)] model, and b) Physics based model. The physics based model solves a set of conservative equations of hydrodynamics using the PLUTO code and can additionally predict the thermal properties of solar wind. The assessment in predicting solar wind parameters of the different models is quantified through statistical measures. We further extend this developed framework to also assess the polarity of inter-planetary magnetic field at L1. Our best models for the case of CR2053 gives a very high correlation coefficient (∼0.73–0.81) and has an root mean square error of (∼75–90 km s−1). Additionally, the physics based model has a standard deviation comparable with that obtained from the hourly OMNI solar wind data and also produces a considerable match with observed solar wind proton temperatures measured at L1 from the same database.
      PubDate: 2020-11-23T00:00:00Z
  • A Mission Concept to Determine the Magnetospheric Causes of Aurora

    • Authors: Joseph E. Borovsky, Gian Luca Delzanno, Michael G. Henderson
      Abstract: Insufficiently accurate magnetic-field-line mapping between the aurora and the equatorial magnetosphere prevents us from determining the cause of many types of aurora. An important example is the longstanding question of how the magnetosphere drives low-latitude (growth-phase) auroral arcs: a large number of diverse generator mechanisms have been hypothesized but equatorial magnetospheric measurements cannot be unambiguously connected to arcs in the ionosphere, preventing the community from identifying the correct generator mechanisms. Here a mission concept is described to solve the magnetic-connection problem. From an equatorial instrumented spacecraft, a powerful energetic-electron beam is fired into the atmospheric loss cone resulting in an optical beam spot in the upper atmosphere that can be optically imaged from the ground, putting the magnetic connection of the equatorial spacecraft’s measurements into the context of the aurora. Multiple technical challenges that must be overcome for this mission concept are discussed: these include spacecraft charging, beam dynamics, beam stability, detection of the beam spot in the presence of aurora, and the safety of nearby spacecraft.
      PubDate: 2020-11-19T00:00:00Z
  • Multiscale and Correlative Analytical Electron Microscopy of
           Extraterrestrial Minerals

    • Authors: Mihaela Albu, Harald Fitzek, David Moser, Gerald Kothleitner, Ferdinand Hofer
      Abstract: This paper presents a unique correlative microscopic method for the structural characterization of extraterrestrial minerals. A fragment from the pallasite Seymchan meteorite that consists of olivine grains mixed into a metallic iron matrix with variable nickel content was studied from mm-down to nm-size by using the Raman Imaging and Scanning Electron Microscopy and analytical scanning transmission electron microscopy. Hyperspectral fast acquisition for energy-dispersive X-ray spectroscopy mapping of a couple of mm2 large area correlated with additional hyperspectral Raman analysis of smaller regions in the same area on one hand, and hyperspectral analytic STEM investigations at the atomic resolution, on the other hand, provided valuable information about the chemical composition, bonding, and crystallography. The analysis revealed particles of troilite, schreibersite, and forsterite but also regions of mixed iron oxides, carbonates, and amorphous carbon as well as plessite regions with nanometre-sized taenite needles dispersed in the kamacite matrix.
      PubDate: 2020-11-19T00:00:00Z
  • UV Irradiation and Near Infrared Characterization of Laboratory Mars Soil
           Analog Samples

    • Authors: Teresa Fornaro, John R. Brucato, Giovanni Poggiali, Maria Angela Corazzi, Malgorzata Biczysko, Maguy Jaber, Dionysis I. Foustoukos, Robert M. Hazen, Andrew Steele
      Abstract: The search for molecular biosignatures at the surface of Mars is complicated by an intense irradiation in the mid- and near-ultraviolet (UV) spectral range for several reasons: (i) many astrobiologically relevant molecules are electronically excited by efficient absorption of UV radiation and rapidly undergo photochemical reactions; (ii) even though the penetration depth of UV radiation is limited, aeolian erosion continually exposes fresh material to radiation; and (iii) UV irradiation generates strong oxidants such as perchlorates that can penetrate deep into soils and cause subsurface oxidative degradation of organics. As a consequence, it is crucial to investigate the effects of UV radiation on organic molecules embedded in mineral matrices mimicking the martian soil, in order to validate hypotheses about the nature of the organic compounds detected so far at the surface of Mars by the NASA Mars Science Laboratory’s (MSL) Curiosity rover, as well as organics that will be possibly found by the next rover missions Mars 2020 (NASA) and ExoMars 2022 (ESA-Roscosmos). In addition, studying the alteration of possible molecular biosignatures in the martian environment will help to redefine the molecular targets for life detection missions and devise suitable detection methods. Here we report the results of mid- and near-UV irradiation experiments of Mars soil analog samples obtained adsorbing relevant organic molecules on a clay mineral that is quite common on Mars, i.e. montmorillonite, doped with 1 wt% of magnesium perchlorate. Specifically, we chose to investigate the photostability of a plausible precursor of the chlorohydrocarbons detected on Mars by the Curiosity rover, namely phthalic acid, along with the biomarkers of extant life L-phenylalanine and L-glutamic acid, which are proteomic amino acids, and adenosine 5’-monophosphate, which is a nucleic acid component. We monitored the degradation of these molecules adsorbed on montmorillonite through in situ spectroscopic analysis, investigating the reflectance properties of the samples in the Near InfraRed (NIR) spectral region. Such spectroscopic characterization of molecular alteration products provides support for two upcoming robotic missions to Mars that will employ NIR spectroscopy to look for molecular biosignatures, through the instruments SuperCam on board Mars 2020, ISEM, Ma_Miss and MicrOmega on board ExoMars 2022.
      PubDate: 2020-11-18T00:00:00Z
  • Editorial: Magnetic Flux Ropes: From the Sun to the Earth and Beyond

    • Authors: Rui Liu, Jie Zhang, Yuming Wang, Hongqiang Song
      PubDate: 2020-11-16T00:00:00Z
  • Planetary Protection in the New Space Era: Science and Governance

    • Authors: Thomas Cheney, Christopher Newman, Karen Olsson-Francis, Scott Steele, Victoria Pearson, Simon Lee
      Abstract: Committee of Space Research’s Planetary Protection Policy is a triumph of technocratic governance in the global sphere. The Policy is produced by a group of scientific experts and subsequently enjoys high regard among the scientific and space community. However, as Committee of Space Research is an independent organization without any legal mandate the Planetary Protection Policy is an example of so-called “soft law” or a non-binding international instrument, in short, no one is under any legal obligation to comply with them. The policy is linked to Article IX of the Outer Space Treaty and its provision calling for the avoidance of “harmful contamination” of the Moon and other celestial bodies. While space activities beyond Earth orbit have been the exclusive preserve of government scientific space agencies this has posed little problem. However as private and “non-science” space activities proliferate and begin to spread their reach beyond Earth orbit, the Planetary Protection Policy is being tested. This paper will examine the challenges of developing and maintaining an effective planetary protection regime in this “New Space” era. This will involve looking at the existing policies, as well as the governance framework they sit within. However, it is also necessary to consider and understand the scientific basis not just for the specifics of the policy itself but the necessity of it. Finally, this paper will consider whether a broader “environmental” framework is needed as space activities diversity in type and location.
      PubDate: 2020-11-13T00:00:00Z
  • A General Overview for Localizing Short Gamma-Ray Bursts with a CubeSat

    • Authors: Fadil Inceoglu, Néstor J. Hernández Marcano, Rune H. Jacobsen, Christoffer Karoff
      Abstract: The gamma-ray burst monitor (GBM) on the Fermi Gamma-Ray Space Telescope, for the first time, detected a short gamma ray burst (SGRB) signal that accompanies a gravitational wave signal GW170817 in 2017. The detection and localization of the gravitational wave and gamma-ray source led all other space- and ground-based observatories to measure its kilonova and afterglow across the electromagnetic spectrum, which started a new era in astronomy, the so-called multi-messenger astronomy. Therefore, localizations of short gamma-ray bursts, as counterparts of verified gravitational waves, are of crucial importance since this will allow observatories to measure the kilonovae and afterglows associated with these explosions. Our results show that an automated network of observatories, such as the Stellar Observations Network Group, can be coupled with an interconnected multi-hop array of CubeSats for transients (IMPACT) to localize SGRBs. IMPACT is a mega-constellation of ∼80 CubeSats, each of which is equipped with gamma-ray detectors with ultrahigh temporal resolution to conduct full sky surveys in an energy range of 50–300 keV and downlink the required data promptly for high-accuracy localization of the detected SGRB to a ground station. Additionally, we analyze propagation and transmission delays from receipt of an SGRB signal to ground station offload to consider the effects of constellation design, link, and network parameters such as satellites per plane, data rate, and coding gain from erasure correcting codes among others. IMPACT will provide near–real-time localization of SGRBs with a total delay of ∼5 s and will enable Stellar Observations Network Group telescopes to join the efforts to pursue multi-messenger astronomy and help decipher the underlying physics of these events.
      PubDate: 2020-11-12T00:00:00Z
  • ANC From Experimental Perspective

    • Authors: Vaclav Burjan, Jaromir Mrazek, Giuseppe D'Agata
      Abstract: In this article, we review the activities of the application of the Asymptotic Normalization Coefficients (ANC) method for the determination of the cross-sections and astrophysical S-factors of the radiative (p, γ) captures, on stable and radioactive nuclei. A number of experiments were conducted at the Nuclear Physics Institute of the Czech Academy of Sciences, in cooperation with Texas A&M University and the Istituto Nazionale di Fisica Nucleare - Laboratori Nazionali del Sud (Catania, Italy). These measurements were performed using solid state detectors and a magnetic spectrometer. This method was introduced in the last decade of the twentieth century and was, at first, used to contribute to the intensively studied topic of solar neutrinos. Later its use was extended from the Li, Be, and B element region to the CNO cycle and above. The obtained results were found (where other measurements were available) to be compatible with other indirect methods and even with direct measurements. While the capacities of direct measurements constantly improve, the advantage of the ANC and other indirect methods in general is still crucial in determining the astrophysical S-factors where short living isotopes participate, e.g., in 11C(p, γ)12N, 12N(p, γ)13O, and 13N(p, γ)14O. The ANC method can also provide predictions for reactions with mirror nuclei. Other uses of ANCs are also discussed.
      PubDate: 2020-11-10T00:00:00Z
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