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Advances in Space Research
Journal Prestige (SJR): 0.569
Citation Impact (citeScore): 2
Number of Followers: 433  
 
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ISSN (Print) 0273-1177
Published by Elsevier Homepage  [3177 journals]
  • New Algorithms to estimate electron temperature and electron density with
           contaminated DC Langmuir probe onboard CubeSat
    • Abstract: Publication date: Available online 30 November 2019Source: Advances in Space ResearchAuthor(s): Shyh-Biau Jiang, Tse-Liang Yeh, Jann-Yenq Liu, Chi-Kuang Chao, Loren C. Chang, Li-Wu Chen, Chung-Jen Chou, Yu-Jung Chi, Yu-Lin Chen, Chen-Kang ChiangAbstractThree algorithms are developed to process the response current of pulsed Langmuir probes (PLPs) onboard satellites estimating ideal pulse current, residual voltage, and the electron temperature (Te) and electron density (Ne) in the ionosphere. The contaminated layer on the probe surface could result in LPs obtaining unreliable Te and Ne. The PLP is designed to solve this problem, and however, the rise time of pulse signals not approaching to zero will still bring some errors. Meanwhile, after each pulse scan, it requires a certain period for discharging, which affects the spatial resolution of PLP measurements. To resolve these problems, three algorithms estimate the ideal pulse response current, calculate the contaminated layer residual voltage to shorten the inter pulse scan period, and compute Te and Ne accordingly. Measurements of the DMSP (Defense Meteorological Satellite Program) are used to validate the performance of the proposed algorithms. Results show that the error of Te and Ne can be reduced down to 5% each, and the scanning rate can be increased by about 5-50 times.
       
  • Trajectory optimization for asteroid landing with two-phase free final
           time
    • Abstract: Publication date: Available online 30 November 2019Source: Advances in Space ResearchAuthor(s): Yingying Zhang, Jiangchuan Huang, Hutao CuiAbstractThis work develops an autonomous trajectory planning algorithm for 6-DOF asteroid landing. The trajectory planning problem is formulated as a nonconvex time-optimal optimization problem with two-phase free final time, while the cost is regularized by augmenting a fuel consumption penalty. The nonconvex optimization problem is solved in successive solution method, so successive convexification is used to convert the original nonconvex problem into a sequence of convex subproblems, where each subproblem is obtained by linearizing the nonconvex dynamics and state constraints and using the velocity increment to give a convex expression of the fuel consumption penalty in cost function. Specifically, in the linearization, we divide the flight time interval into two parts and normalize each part using a time dilation coefficient to solve the problem that both the final times for the two flight phases are unknown, so that the original free final time problem turns to a fixed-time problem by minimizing the sum of the two time dilation coefficients and fuel consumption penalty. Besides, trust regions and virtual control are used to increase robustness of the algorithm. A convergence analysis is presented which indicates the successive solution will recover the local optimality of the original problem. Then the validity of the proposed algorithm and effects of different factors on flight time and fuel consumption are examined by simulations of landing on an irregular asteroid.
       
  • Developing a dust storm detection method combining Support Vector Machine
           and satellite data in Typical dust regions of Asia
    • Abstract: Publication date: Available online 28 November 2019Source: Advances in Space ResearchAuthor(s): Lamei Shi, Jiahua Zhang, Da Zhang, Tertsea Igbawua, Yuqin LiuAbstractEnhancing the dust storm detection is a key part for the environmental protection, human healthy and economic development. The goal of this paper is to propose a new Support Vector Machine (SVM)-based method to automatically detect dust storms using remote sensing data. Existing methods dealing with this problem are usually threshold-based that are of great complexity and uncertainty. In this paper we propose a simple and reliable method combining SVM with MODIS L1 data and explore the optimal band combinations used as the feature vectors of SVM. The developed method was evaluated by MODIS and OMI data qualitatively and quantitatively on three study sites located in the Arabian Desert, Gobi Desert and Taklimakan Desert, and it was also compared to three other traditional methods based on their accuracy, complexity, reliability and sensitivity to thresholds. The detection results demonstrated that the combination of (Band7-Band3)/(Band7+Band3) ((B7-B3)/(B7+B3)), Band20-Band31 (B20-B31), and Band31/Band32 (B31/B32) can detect the dust storms more precisely than other individual bands or their combination. The comparison among those cases indicated that the proposed automatic method exhibited an advantage of minimizing the uncertainty and complexity, which were the limits of defining thresholds based on the threshold-based methods. The conclusions can provide references for studies that focus on statistical-based dust storm detection.
       
  • A Sequential Estimation Approach to Terrestrial Reference Frame
           Determination
    • Abstract: Publication date: Available online 26 November 2019Source: Advances in Space ResearchAuthor(s): Claudio Abbondanza, Toshio M. Chin, Richard S. Gross, Michael B. Heflin, Jay W. Parker, Benedikt S. Soja, Xiaoping WuAbstractWe review the main concepts underlying the determination of terrestrial reference frames (TRFs) through a recursive algorithm based on Kalman Filtering and Rauch-Tung-Striebel (RTS) smoothing which is currently adopted at Jet Propulsion Laboratory (JPL) to compute sub-secular frame products (JTRFs). We contextualize the TRF determination in the state-space framework and we emphasize connections between frame state, its observability through space-geodetic frame inputs and the similarity transformation which is central to frame definition. We elaborate on the notion of sub-secular frame, enabled by our approach, in constrast to standard TRF products which, secular by construction, are designed to represent the long-term mean physical properties of the frame. Comparisons of JTRF solutions to standard products such as the International Terrestrial Reference Frame (ITRF) suggest high-level consistency in a long-term sense with time derivatives of the Helmert transformation parameters connecting the two TRFs below 0.18 mm/yr. We discuss advantages and limitations of JPL approach to TRF determination and outline lines of inquiries that are currently being researched as part of JTRF development plan.
       
  • Optimal Solar Sail Trajectory Approximation with Finite Fourier Series
    • Abstract: Publication date: Available online 26 November 2019Source: Advances in Space ResearchAuthor(s): Andrea Caruso, Marco Bassetto, Giovanni Mengali, Alessandro A. QuartaAbstractThe heliocentric transfer of a solar sail-based spacecraft is usually studied from an optimal perspective, by looking for the control law that minimizes the total flight time. The optimal control problem can be solved either with an indirect approach, whose solution is difficult to obtain due to its sensitivity to an initial guess of the costates, or with a direct method, which requires a good estimate of a feasible (guess) trajectory. This work presents a procedure to generate an approximate optimal trajectory through a finite Fourier series. The minimum time problem is solved using a nonlinear programming solver, in which the optimization parameters are the coefficients of the Fourier series and the positions of the spacecraft along the initial and target orbits. Suitable constraints are enforced on the direction and magnitude of the sail propulsive acceleration vector in order to obtain feasible solutions. A comparison with the numerical results from an indirect approach shows that the proposed method provides a good approximation of the optimal trajectory with a small computational effort.
       
  • Simulation of long-term rotational dynamics of large space debris: A
           TOPEX/Poseidon case study
    • Abstract: Publication date: Available online 26 November 2019Source: Advances in Space ResearchAuthor(s): Luc B. M. Sagnières, Inna Sharf, Florent DeleflieAbstractAccurate knowledge of the rotational dynamics of a large space debris is crucial for space situational awareness (SSA), whether it be for accurate orbital predictions needed for satellite conjunction analyses or for the success of an eventual active debris removal mission charged with stabilization, capture and removal of debris from orbit. In this light, the attitude dynamics of an inoperative satellite of great interest to the space debris community, the joint French and American spacecraft TOPEX/Poseidon, is explored. A comparison of simulation results with observations obtained from high-frequency satellite range measurements is made, showing that the spacecraft is currently spinning about its minor principal axis in a stable manner. Predictions of the evolution of its attitude motion to 2030 are presented, emphasizing the uncertainty on those estimates due to internal energy dissipation, which could cause a change of its spin state in the future. The effect of solar radiation pressure and the eddy-current torque are investigated in detail, and insights into some of the satellite’s missing properties are provided. These results are obtained using a novel, open-source, coupled orbit-attitude propagation software, the Debris SPin/Orbit Simulation Environment (D-SPOSE), whose primary goal is the study of the long-term evolution of the attitude dynamics of large space debris.
       
  • A multilayer perceptron and multiclass support vector machine based high
           accuracy technique for daily rainfall estimation from MSG SEVIRI data
    • Abstract: Publication date: Available online 25 November 2019Source: Advances in Space ResearchAuthor(s): Mounir Sehad, Soltane AmeurAbstractThe current paper introduces a new multilayer perceptron (MLP) and support vector machine (SVM) based approach to improve daily rainfall estimation from the Meteosat Second Generation (MSG) data. In this study, the precipitation is first detected and classified into convective and stratiform rain by two MLP models, and then four multi-class SVM algorithms were used for daily rainfall estimation. Relevant spectral and textural input features of the developed algorithms were derived from the spectral MSG SEVIRI radiometer channels. The models were trained using radar rainfall data set colected over north Algeria. Validation of the proposed daily rainfall estimation technique was performed by rain gauge network data set recorded over north Algeria. Thus, several statistical scores were calculated, such as correlation coefficient (r), root mean square error (RMSE), mean error (Bias), and mean absolute error (MAE). The findings given by: (r =0.97, bias=0.31mm, RMSE = 2.20mm and MAE =1.07mm), showed a quite satisfactory relationship between the estimation and the respective observed daily precipitation. Moreover, the comparison of the results with those of two advanced techniques based on random forests (RF) and weighted ‘k’ nearest neighbor (WkNN) showed higher accuracy obtained by the proposed model.
       
  • Cumulative Author Index for Volume 64
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s):
       
  • A charge sharing study of silicon microstrip detectors with electrical
           characterization and SPICE simulation
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Rui Qiao, Wen-Xi Peng, Xing-Zhu Cui, Guang-Qi Dai, Yi-Fan Dong, Rui-Rui Fan, Min Gao, Ke Gong, Dong-Ya Guo, Xiao-Hua Liang, Ya-Qing Liu, Huan-Yu Wang, Jin-Zhou Wang, Di Wu, Jia-Wei Yang, Fei Zhang, Hao ZhaoAbstractSilicon microstrip detectors with floating strips have nonuniform charge collection efficiency. This nonuniformity depends on the incident position and incident angle and should be corrected during charge reconstruction. A novel charge reconstruction algorithm, called the charge sharing algorithm, is introduced to correct this nonuniformity. This algorithm assumes that the nonuniformity in charge collection efficiency is due to charge sharing through the capacitors and resistors of silicon microstrip detectors. This charge sharing assumption is tested in this paper using electrical characterization and SPICE simulation.
       
  • The HERO (High Energy Ray Observatory) detector current status
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): D. Karmanov, A. Panov, D. Podorozhny, L. Tkachev, A. TurundaevskiyAbstractIn this paper, the goals and scientific tasks of the space experiment “High Energy Rays Observatory” (HERO) are established. The preliminary design of the scientific equipment is presented, the characteristic features of which are its high geometric factor (up to ∼20 m2 sr) and adequate energy measurement resolution (20–30% or better, depending on the type of components). The ionisation tungsten-scintillator calorimeter is used for energy measurement. The total calorimeter weight is equal to 12 tons. The technical characteristics of the equipment permit the direct study of cosmic rays in a wide energy range, including the unexplored region of 1015–1016 eV. The current status of the space experiment is discussed. Currently, the HERO project is in its pre-R&D phase. The launch of the satellite is planned for between 2025 and 2030.
       
  • NUCLEON-2 mission for the investigation of isotope and charge composition
           of cosmic ray ions
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): V. Bulatov, S. Fillippov, D. Karmanov, I. Kovalev, A. Kurganov, M. Panasyuk, A. Panov, D. Podorozhny, D. Polkov, L. Tkatchev, P. Tkatchev, A. Turundaevskiy, O. VasilievAbstractThe NUCLEON-2 experiment is aimed at the investigation of isotope and charge composition of medium, heavy and ultra-heavy ions (Z
       
  • Targeting ultra-high energy neutrinos with the ARIANNA experiment
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): A. Anker, S.W. Barwick, H. Bernhoff, D.Z. Besson, N. Bingefors, G. Gaswint, C. Glaser, A. Hallgren, J.C. Hanson, R. Lahmann, U. Latif, J. Nam, A. Novikov, S.R. Klein, S.A. Kleinfelder, A. Nelles, M.P. Paul, C. Persichilli, S.R. Shively, J. TatarAbstractThe measurement of ultra-high energy (UHE) neutrinos (E > 1016 eV) opens a new field of astronomy with the potential to reveal the sources of ultra-high energy cosmic rays especially if combined with observations in the electromagnetic spectrum and gravitational waves. The ARIANNA pilot detector explores the detection of UHE neutrinos with a surface array of independent radio detector stations in Antarctica which allows for a cost-effective instrumentation of large volumes. Twelve stations are currently operating successfully at the Moore’s Bay site (Ross Ice Shelf) in Antarctica and at the South Pole. We will review the current state of ARIANNA and its main results. We report on a newly developed wind generator that successfully operates in the harsh Antarctic conditions and powers the station for a substantial time during the dark winter months. The robust ARIANNA surface architecture, combined with environmentally friendly solar and wind power generators, can be installed at any deep ice location on the planet and operated autonomously. We report on the detector capabilities to determine the neutrino direction by reconstructing the signal arrival direction of a 800 m deep calibration pulser, and the reconstruction of the signal polarization using the more abundant cosmic-ray air showers. Finally, we describe a large-scale design – ARIA – that capitalizes on the successful experience of the ARIANNA operation and is designed sensitive enough to discover the first UHE neutrino.
       
  • Red dwarfs as sources of cosmic rays and detection of TeV gamma-rays from
           these stars
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Vera G. Sinitsyna, Vera Y. Sinitsyna, Yurii I. StozhkovAbstractA modern paradigm on the sources of galactic cosmic rays includes supernovae and supernova remnants as the powerful ones to accelerate particles up to ∼1017 eV. Meanwhile, the recent experimental data obtained by PAMELA, AMS-02, Fermi-LAT, CALET, and DAMPE require the existence of other cosmic-ray sources located nearby the solar system, at the distances less than 1 kpc. Presence of such local sources could explain the unexpected rise of the positron fraction in cosmic rays, the observed electron fluxes with the energies more than one TeV, complex shapes of the proton and helium spectra, and anomalous low-energy cosmic rays. Here we consider active dwarf stars as possible sources of Galactic cosmic rays in the energy range up to 1014 eV. These stars are producing powerful stellar flares sometimes with energy release more than 1036 erg. Meanwhile, the generation of high-energy cosmic rays should be accompanied by the high-energy γ-ray emission, which may be observed. Here we present the results of the SHALON long-term observations of generation of γ-ray emission above 800 GeV from the active red dwarf stars.
       
  • Mass composition of cosmic rays above 0.1 EeV by the Yakutsk array
           data
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): S. Knurenko, I. PetrovAbstractThe paper presents the results of the longitudinal development of extensive air showers (Xmax) of ultra-high energies and mass composition of cosmic rays. The measurements of Xmax are based on data from observations of the Cherenkov radiation at the Yakutsk array for the period 1974–2014. The cascade curves of individual showers and the depth of maximum Xmax were reconstructed over the energy range 1016–5.7 · 1019 eV. It is shown that the displacement rate of the parameter dXmax/dE in the atmosphere is nonlinear and depends on the energy. Such a feature indicates a change in mass composition, which is confirmed by fluctuations of Xmax in this energy region. The composition of cosmic rays was determined by interpolation using the QGSJetII-04 model.
       
  • On-orbit performance of the top and bottom counting detectors for the
           ISS-CREAM experiment on the international space station
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): S.C. Kang, Y. Amare, T. Anderson, D. Angelaszek, N. Anthony, K. Cheryian, G.H. Choi, M. Copley, S. Coutu, L. Derome, L. Eraud, L. Hagenau, J.H. Han, H.G. Huh, Y.S. Hwang, H.J. Hyun, S. Im, H.B. Jeon, J.A. Jeon, S. JeongAbstractThe Cosmic Ray Energetics And Mass (CREAM) instrument on the International Space Station (ISS) is an experiment to study origin, propagation, acceleration and elemental composition of cosmic rays. The Top Counting Detector (TCD) and Bottom Counting Detector (BCD) are parts of the detector suite of the ISS-CREAM experiment and are designed to separate electrons and protons for studying electron and gamma-ray physics. In addition, the TCD/BCD provide a redundant trigger to that of the calorimeter and a low energy trigger to the ISS-CREAM instrument. After launching, the TCD/BCD trigger was found to be working well. Also, the TCD/BCD have been stable and their hit positions were confirmed to be well matched with other detectors on board. We present the performance and status of the TCD/BCD in flight.
       
  • Secondary cosmic rays in the NUCLEON space experiment
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): V. Grebenyuk, D. Karmanov, I. Kovalev, I. Kudryashov, A. Kurganov, A. Panov, D. Podorozhny, A. Tkachenko, L. Tkachev, A. Turundaevskiy, O. Vasiliev, A. VoroninAbstractThe NUCLEON space observatory is a direct cosmic ray spectrometer designed to study cosmic ray nuclei with Z=1-30 at energies 1012-1015 eV. It was launched as an additional payload onboard the Russian Resource-P No. 2 satellite in December of 2014. In this work B/C, N/O and subFe/Fe ratios are presented. The experiment has worked for half of its expected time, so the data have preliminary status, but they already give clear indications of several astrophysical phenomena, which are briefly discussed in this paper.
       
  • Energy spectra of abundant cosmic-ray nuclei in the NUCLEON experiment
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): V. Grebenyuk, D. Karmanov, I. Kovalev, I. Kudryashov, A. Kurganov, A. Panov, D. Podorozhny, A. Tkachenko, L. Tkachev, A. Turundaevskiy, O. Vasiliev, A. VoroninAbstractThe NUCLEON satellite experiment is designed to directly investigate the energy spectra of cosmic-ray nuclei and the chemical composition (Z = 1–30) in the energy range of 2–500 TeV. The experimental results are presented, including the energy spectra of different abundant nuclei measured using the new Kinematic Lightweight Energy Meter (KLEM) technique. The primary energy is reconstructed by registration of spatial density of the secondary particles. The particles are generated by the first hadronic inelastic interaction in a carbon target. Then additional particles are produced in a thin tungsten converter, by electromagnetic and hadronic interactions. The deconvolution of spectra was performed. Statistical errors were presented.
       
  • List of Referees
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s):
       
  • Antiproton flux and properties of elementary particle fluxes in primary
           cosmic rays measured with the Alpha Magnetic Spectrometer on the
           International Space Station
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Zhili WengAbstractPrecision measurements by AMS of the antiproton flux and the antiproton-to-proton flux ratio in primary cosmic rays in the absolute rigidity range from 1 to 525 GV is presented, together with the fluxes and flux ratios of charged elementary particles in cosmic rays up to 1 TV. In the absolute rigidity range 60–500 GV, the antiproton p¯, proton p and positron e+ fluxes are found to have nearly identical rigidity dependence and the electron e- flux exhibits different rigidity dependence. From 60GV to 500 GV, the p¯/p,p¯/e+ and p/e+ flux ratios are rigidity independent. These AMS measurements continue to reveal important properties of cosmic ray elementary particle fluxes and provide invaluable input towards understanding the origin of many observed unexpected phenomena.
       
  • Distinctive properties of cosmic-ray positron and electron fluxes measured
           by AMS on ISS
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Weiwei XuAbstractThe precise AMS data reveals distinctive properties of cosmic-ray positron and electron fluxes. The positron spectrum hardens starting from ∼20 GeV. Most importantly, the positron spectrum exhibits a sharp drop-off at ∼300 GeV, showing the existence of an energy cutoff at highest energy. The electron spectrum is distinctly different from the positron spectrum in both the magnitude and energy dependence. The electron spectrum hardens from ∼30 GeV. Remarkably, the electron spectrum is well described by a single power law from 55 GeV to 1 TeV and does not have an energy cutoff. These experimental data show that, at high energies, the cosmic-ray positrons predominately originate either from dark matter annihilation or from a new astrophysical source, whereas the cosmic-ray electrons originate from different sources.
       
  • Is it possible to organize automatic forecasting of expected radiation
           hazard level from Solar Cosmic Ray (SCR) events for spacecraft in the
           
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Lev Dorman, Lev Pustil'nik, Uri Dai, Mark Idler, Fatima Keshtova, Elizabeth PetrovAbstractWe present the method of automatic forecasting of the impacts of Solar Cosmic Ray (SCR)/Solar Energetic Particle (SEP) and estimation of radiation hazard level. We use the model of SCR/SEP diffusion in general form and coupling functions for neutron monitors of worldwide network with different altitudes and cutoff rigidities, including space detectors such as GOES-11,12. Another observational data for the estimation of energy spectra of SCR/SEP are measurements of different neutron multiplicities by some neutron monitors (e.g., for great SCR/SEP event held in September 29, 1989). A 1-min data of muon telescopes and ionization chambers shielded by 10-cm PB are used for the detection of the highest-energy SCR/SEP components (e.g., for SCR/SEP events held on February 23, 1956; Dorman, 1957). We demonstrate algorithms to automatically estimate event starting times, determine the time evolution of SCR/SEP in space using coupling functions in the frame of spectrographic method, solve inverse problems associated with SCR/SEP generation in solar corona and propagation in the interplanetary space, automatically determine escaping into solar wind and propagation in space based on the CR observation data parameters of SCR/SEP generation and propagation in solar corona. Based on these parameters, we show that it is possible to automatically forecast the first 0.5 h data on expected level of radiation hazards from a full-time event (up to about 48 h) for objects in space on different distances from the Sun, in magnetosphere at different orbits, and in atmosphere at different altitudes and cutoff rigidities. It is important, before the start of the automatic forecasting procedure, to calculate the expected level of radiation hazards for full time of event by determining every 5–10 min recalculated forecasting fluxes of SCR/SEP in space, out of magnetosphere, back to the CR ground detectors, and detectors on satellites using the same coupling functions. If the difference between the obtained results and observed data is smaller or no statistical errors, it is possible to provide effective forecasting automatically and subsequently calculate the expected level of radiation hazards. If the expected level of radiation hazards is high in certain objects, after about 0.5 h from the event starting time, it will be formatted and a corresponding alert is sent. The same alerts will be repeated with time for different objects in space, in magnetosphere, and in atmosphere. Based on the first 0.5 h data from event beginning, the radiation hazard level from high-energy particles such as SCR/SEP is considered to be low (with very small flux). If with increasing time the radiation hazard level rises with energy ≤1 GeV, it is formatted. Also, at the beginning of some SCR/SEP events when the Earth is on or near the force line of IMF connected with the source of SCR/SEP, several CR stations with direct arriving along the magnetic force line with about no scattering SCR/SEP particles on magnetic inhomogeneities will show strong narrow pulse with no information on SCR/SEP diffusion during the propagation from the source to the detector. These CR stations at the beginning of the SCR/SEP event can be used only for estimating SCR/SEP energy spectrum in the source and at the time of injection into solar wind but not on diffusion. Hence, it is necessary to automatically separate the CR stations with strong narrow pulses and exclude them from diffusion analysis. We strive to make this automatic using a program of image identification in the frame of MATLAB.
       
  • Numerical modeling of cosmic-ray transport in the heliosphere and
           interpretation of the proton-to-helium ratio in Solar Cycle 24
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Nicola Tomassetti, Fernando Barão, Bruna Bertucci, Emanuele Fiandrini, Miguel OrcinhaAbstractThanks to space-borne experiments of cosmic-ray (CR) detection, such as the AMS and PAMELA missions in low-Earth orbit, or the Voyager-1 spacecraft in the interstellar space, a large collection of multi-channel and time-resolved CR data has become available. Recently, the AMS experiment has released new precision data, on the proton and helium fluxes in CRs, measured on monthly basis during its first six years of mission. The AMS data reveal a remarkable long-term behavior in the temporal evolution of the proton-to-helium ratio at rigidity R≡p/Z≲,3 GV. As we have argued in a recent work, such a behavior may reflect the transport properties of low-rigidity CRs in the inteplanetary space. In particular, it can be caused by mass/charge dependence of the CR diffusion coefficient. In this paper, we present our developments in the numerical modeling of CR transport in the Milky Way and in the heliosphere. Within our model, and with the help of approximated analytical solutions, we describe in details the relations between the properties of CR diffusion and the time-dependent evolution of the proton-to-helium ratio.
       
  • elMod+model+in+the+works+for+inner+and+outer+heliosphere:+From+AMS+to+Voyager+probes+observations&rft.title=Advances+in+Space+Research&rft.issn=0273-1177&rft.date=&rft.volume=">The HelMod model in the works for inner and outer heliosphere: From AMS to
           Voyager probes observations
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): M.J. Boschini, S. Della Torre, M. Gervasi, G. La Vacca, P.G. RancoitaAbstractHelMod is a Monte Carlo code developed to describe the transport of Galactic Cosmic Rays (GCRs) through the heliosphere from the interstellar space to the Earth. In the current HelMod version 4 the modulation process, based on Parker’s equation, is applied to the propagation of GCRs in the inner and outer heliosphere, i.e., including the heliosheath. HelMod was proved to reproduce protons, nuclei and electrons cosmic rays spectra observed during solar cycles 23–24 by several detectors, for instance, PAMELA, BESS and AMS-02. In particular, the unprecedented accuracy of AMS-02 observations allowed one a better tuning of the description regarding the solar modulation mechanisms implemented in HelMod. In addition, HelMod demonstrated to be capable of reproducing the fluxes observed by the Voyager probes in the inner and outer regions of heliosphere up to its border.
       
  • High energy interactions of cosmic rays
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Sergey OstapchenkoAbstractA discussion of a number of important topics related to modeling of high energy cosmic ray interactions is presented. Special attention is devoted to novel theoretical approaches employed in event generators of hadronic interactions and to the impact of experimental data from the Large Hadron Collider (LHC). In relation to studies of ultra-high energy cosmic rays (UHECRs), differences between various predictions for basic characteristics of UHECR-induced extensive air showers in the atmosphere are analyzed and traced down to differences in the respective treatments of hadronic interactions. Possibilities to discriminate between the alternative approaches, based on LHC and UHECR data, are demonstrated and the relation to UHECR primary composition is outlined. Finally, in relation to direct studies of charged cosmic rays, potential improvements of the treatment of cosmic ray interactions at low and intermediate energies are discussed.
       
  • High-energy cosmic rays from compact galactic star clusters: Particle
           fluxes and anisotropy
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): A.M. Bykov, M.E. Kalyashova, D.C. Ellison, S.M. OsipovAbstractIt has been shown that supernova blast waves interacting with winds from massive stars in compact star clusters may be capable of producing cosmic-ray (CR) protons to above 1017 eV. We give a brief description of the colliding-shock-flow mechanism and look at generalizations of the diffusion of ∼100 PeV CRs in the turbulent galactic magnetic field present in the galactic disk. We calculate the temporal evolution of the CR anisotropy from a possible distribution of young compact massive star clusters assuming the sources are intermittent on time scales of a few million years, i.e., comparable to their residence time in the Milky Way. Within the confines of our model, we determine the galactic/extra-galactic fraction of high-energy CRs resulting in anisotropies consistent with observed values. We find that galactic star clusters may contribute a substantial fraction of ∼100 PeV CRs without producing anisotropies above observed limits.
       
  • Field line random walk, field line separation, and particle transport in
           turbulence with weak transverse complexity
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): A. ShalchiAbstractWe study the random walk of magnetic field lines as well as field line separation in a magnetized plasma such as the solar wind or the interstellar medium. By doing so we focus on turbulence with small Kubo numbers. For field line random walk this allows us to employ an approach based on a Taylor expansion which is essentially an expansion in the Kubo number. Compared to previous non-linear descriptions, no assumption concerning the field line distribution or diffusivity has to be made. Based on this approach, we compute corrections to the quasi-linear formula allowing us also to test assumptions usually made in non-linear theories of field line random walk. We show that up to the considered order, the assumption of Gaussian statistics does not alter the diffusion coefficient whereas the diffusion approximation provides a correction term which is a factor two too large. We also discuss the separation of two magnetic field lines. We develop a quasi-linear theory for field line separation and introduce a fundamental scale of turbulence describing its transverse structure. Furthermore, we discuss applications of our results in the theory of energetic particle transport. Besides quasi-linear diffusion we also discuss compound sub-diffusion as well as the recovery of diffusion due to transverse complexity. Furthermore, we derive a formula for the perpendicular diffusion coefficient of energetic particles similar compared to the famous Rechester & Rosenbluth result. Applications in astrophysics are also discussed.
       
  • Cosmic ray origin: Why cosmic ray (Astroparticle) phenomenon is universal
           in the Universe' What is the main driver of cosmic ray particle
           generation'
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Lev DormanAbstractDuring many years energetic particles generated on the Sun were called as Solar Cosmic Rays (SCR), but now increased the tendency to rename this phenomenon as Solar Energetic Particles (SEP) event. We will show that SEP, as well as energetic particles generated in magnetospheres of the Earth, Jupiter, Saturn and other planets, in interplanetary space, and in atmospheres of stars have the same nature as Galactic and Intergalactic CR: they are all runaway particles from the Maxwell-Boltzmann distribution of background plasma where they were generated. Energy of these run-away particles is much higher than average energy of background thermal particles. It is shown in this paper that the energy of all these run-away particles have the same general nature: it is always transfer energy from the Macro-objects and Macro-processes directly to Micro World (to charged runaway particles). This transfer energy is formatted in dynamic plasma with frozen in magnetic fields: really magnetic fields ‘glues’ billions thermal background particles into Macro-objects and Macro-processes. So, thank to frozen in magnetic fields runaway particles can interact not only with thermal background particles (and loose energy), but also directly with Macro-objects and Macro-processes with very high macro-energy (many order higher than energy of run-away particle). Thermodynamically Macro-objects and Macro-processes have much bigger “effective temperature” than runaway particles and though the energy always transferred from Macro World to runaway particles of Micro World. We come to conclusion that main cause of origin of all types of Cosmic Rays in the Universe is the transform energy from Macro-world directly to Micro-world through frozen in magnetic fields in plasmas. At the stage when in early Universe were formatted small density plasmas objects with frozen in magnetic fields, where formatted also Cosmic Rays of different types, but these “relict” Cosmic Ray particles have now very small energy thanks to extension Universe. So, observed now CR particles of different types are generated continuously by transfer energy from Macro World to runaway charged particles of Micro World through frozen in magnetic fields (including the main sources as Supernova explosions, Supernova remnants, and some smaller sources, as stars, star’s winds, planetary magnetospheres, and others).
       
  • Advances in cosmic-ray astrophysics and related areas
    • Abstract: Publication date: 15 December 2019Source: Advances in Space Research, Volume 64, Issue 12Author(s): Igor V. Moskalenko, Eun-Suk Seo
       
  • Tube-based robust output feedback model predictive control for autonomous
           rendezvous and docking with a tumbling target
    • Abstract: Publication date: Available online 22 November 2019Source: Advances in Space ResearchAuthor(s): Kaikai Dong, Jianjun Luo, Zhaohui Dang, Liwa WeiAbstractIn this paper, a tube-based robust output feedback model predictive control method (TRMPC) is proposed for controlling chaser spacecraft docking with a tumbling target in near-circular orbit. The controller contains a simple, stable, Luenberger state estimator and a tube-based robust model predictive controller. Several practical challenges are also considered under dock-enabling conditions, such as the control saturation, velocity constraint, approach corridor constraint, and collision avoidance constraint. Meanwhile, uncertainties are carefully analyzed when designing the controller, including dynamics uncertainty, measurement error, and control deviation. The TRMPC ensures that all possible state trajectories with uncertainties lie in the minimum robust positively invariant set (mRPI, i.e., the so-called tube in this paper). The tube center is the solution of a nominal (without uncertainties) system. Another important contribution of this paper is to propose a technique where it is unnecessary to calculate the mRPI explicitly. Thereby, the ‘curse of dimensionality’ can be avoided for a six-dimensional system. To verify the feasibility of the proposed TRMPC strategy in the presence of uncertainties, two scenarios of autonomous rendezvous and docking (AR&D) are simulated. The simulation results show that the TRMPC method is more efficient in minimizing the uncertainties, fuel consumption, and computational cost, compared to the classic model predictive control (MPC) method.
       
  • Magnetic fields in isolated and interacting white dwarfs
    • Abstract: Publication date: Available online 21 November 2019Source: Advances in Space ResearchAuthor(s): Lilia Ferrario, Dayal Wickramasinghe, Adela KawkaAbstractThe magnetic white dwarfs (MWDs) are found either isolated or in interacting binaries. The isolated MWDs divide into two groups: a high field group (HFMWDs: 105-109 G) comprising some 13±4% of all white dwarfs (WDs), and a low field group (LFMWDs: B
       
  • A realistic simulation framework to evaluate ionospheric tomography
    • Abstract: Publication date: Available online 20 November 2019Source: Advances in Space ResearchAuthor(s): Jon Bruno, Cathryn N. Mitchell, Karl H.A. Bolmgren, Ben A. WitvlietAbstractObservation of the 3-dimensional (3-D) electron density of the ionosphere is useful to study large-scale physical processes in space weather events. Ionospheric data assimilation and ionospheric tomography are methods that can create an image of the 3-D electron density distribution. While multiple techniques have been developed over the past 30 years, there are relatively few studies that show the accuracy of the algorithms. This paper outlines a novel simulation approach to test the quality of an ionospheric tomographic inversion. The approach uses observations from incoherent scatter radar (ISR) scans and extrapolates them spatially to create a realistic ionospheric representation. A set of total electron content (TEC) measurements can then be simulated using real geometries from satellites and ground receivers. This data set, for which the ’truth’ ionosphere is known, is used as input for a tomographic inversion algorithm to estimate the spatial distribution of electron density. The reconstructed ionospheric maps are compared with the truth ionosphere to calculate the difference between the images and the truth.To demonstrate the effectiveness of this simulation framework, an inversion algorithm called MIDAS (Multi-Instrument Data Analysis Software) is evaluated for three geographic regions with differing receiver networks. The results show the importance of the distribution and density of GPS receivers and the use of a realistic prior conditioning of the vertical electron density profile. This paper demonstrates that when these requirements are met, MIDAS can reliably estimate the ionospheric electron density. When the region under study is well covered by GPS receivers, as in mainland Europe or North America, the errors in vertical total electron content (vTEC) are smaller than 1 TECu (2-4%) . In regions with fewer and more sparsely distributed receivers, the errors can be as high as 20-40%. This is caused by poor data coverage and poor spatial resolution of the reconstruction, which has an important effect on the calibration process of the algorithm.
       
  • PD β +Based+Sliding+Mode+Control+Algorithms+with+Modified+Reaching+Law+for+Satellite+Attitude+Maneuver&rft.title=Advances+in+Space+Research&rft.issn=0273-1177&rft.date=&rft.volume=">PD and PD β Based Sliding Mode Control Algorithms with Modified
           Reaching Law for Satellite Attitude Maneuver
    • Abstract: Publication date: Available online 20 November 2019Source: Advances in Space ResearchAuthor(s): Debajyoti Chakrabarti, Selvaganesan NarayanasamyAbstractAttitude Determination and Control System of a satellite, can be regarded as one of the major subsystems of satellite design. The dynamics and kinematics of the satellite are important to design a controller. In this paper, the nonlinear mathematical model of a satellite is formulated using quaternions. Further, reaction wheel assembly is chosen as an actuator which provides the necessary torque to control the satellite attitude. To stabilize the satellite at desired attitude and angular velocity, PD and PDβ based sliding mode controllers with modified reaching law are proposed. An optimization problem is presented to tune the parameters of the proposed controllers. Numerical simulation is carried out for the satellite system with the tuned controllers at various operating conditions such as (i) without disturbance, (ii) with disturbance and (iii) robustness towards parameter uncertainty. The results of the proposed controllers are compared with conventional PD and PDβ sliding mode controllers.
       
  • Analysis of Laser Ranges and Angular Measurements Data Fusion for Space
           Debris Orbit Determination
    • Abstract: Publication date: Available online 18 November 2019Source: Advances in Space ResearchAuthor(s): E. Cordelli, A. Vananti, T. SchildknechtAbstractIn the framework of space debris, the orbit determination process is a fundamental step, both, for researchers and for satellite operators. The accurate knowledge of the orbit of space debris objects is needed to allow space debris characterization studies and to avoid unnecessary collision avoidance maneuvers.The accuracy of the results of an orbit determination process depends on several factors as the number, the accuracy, the kind of processed measurements, their distribution along the orbit, and the object-observer relative geometry. When the observation coverage of the target orbit is not homogeneous, the accuracy of the orbit determination can be improved processing different kind of observables. Recent studies showed that the satellite laser ranging technique can be successfully applied to space debris.In this paper, we will investigate the benefits of using laser ranges and angular measurements for the orbit determination process. We will analyze the influence of the number of used observations, of the covered arc of orbit, of each observable, and of the observation geometry on the estimated parameters. Finally, using data acquired on short observation arcs, we analyze the achievable accuracies for the orbital regimes with the highest space debris density, and to the consequences of the data fusion on catalog maintenance operations. The results shown are obtained using only real data (both angular and laser measurements) provided by sensors of the Swiss Optical Ground Station and Geodynamics Observatory Zimmerwald owned by the Astronomical Institute of the University of Bern (AIUB) and for some studies also using ranges provided from other stations of the International Laser Ranging Service (ILRS).
       
  • Motion-Planning and Pose-Tracking Based Rendezvous and Docking with a
           Tumbling Target
    • Abstract: Publication date: Available online 18 November 2019Source: Advances in Space ResearchAuthor(s): Bang-Zhao Zhou, Xiao-Feng Liu, Guo-Ping CaiAbstractRendezvous and docking (RVD) with a tumbling target is challenging. In this paper, a novel control scheme based on motion planning and pose (position and attitude) tracking is proposed to solve the pose control of a chaser docking with a tumbling target in the phase of close range rendezvous. Firstly, the current desired motion of the chaser is planned according to the motion of the target. In planning the desired motion, the “approach path constraint” is considered to avoid collisions between the chaser and the target, and the “field-of-view constraint” is considered to make sure the vision sensors on the chaser to obtain tight relative pose knowledge of the target with respect to the chaser. Then, the difference between the chaser’s motion and the desired motion is gradually reduced by a pose tracking controller. This controller is based on the non-singular terminal sliding mode (NTSM) method to make the tracking error converge to zero in finite time. Since the chaser nearly moves along the desired motion and the motion is reasonable, (1) it could safely arrive at the docking port of the target with a suitable relative attitude, (2) it will be always suitably oriented to observe the target well, and (3) the magnitude of the needed control inputs are less than that in existing literatures. The numerical results demonstrate the above three advantages of the proposed method.
       
  • Gaia: the Galaxy in six (and more) dimensions
    • Abstract: Publication date: Available online 18 November 2019Source: Advances in Space ResearchAuthor(s): Elena PancinoAbstractThe ESA cornerstone mission Gaia was successfully launched in 2013, and is now scanning the sky to accurately measure the positions and motions of about two billion point-like sources of 3≲V≲20.5 mag, with the main goal of reconstructing the 6D phase space structure of the Milky Way. The typical uncertainties in the astrometry will be in the range 30-500 μas. The sky will be repeatedly scanned (70 times on average) for five years or more, adding the time dimension, and the Gaia data are complemented by mmag photometry in three broad bands, plus line-of-sight velocities from medium resolution spectroscopy for brighter stars. This impressive dataset is having a large impact on various areas of astrophysics, from solar system objects to distant quasars, from nearby stars to unresolved galaxies, from binaries and extrasolar planets to light bending experiments. This invited review paper presents an overview of the Gaia mission and describes why, to reach the goal performances in astrometry and to adequately map the Milky Way kinematics, Gaia was also equipped with state-of-the-art photometers and spectrographs, enabling us to explore much more than the 6D phase-space of positions and velocities. Scientific highlights of the first two Gaia data releases are briefly presented.
       
  • Particle Telescope aboard FORESAIL-1: simulated performance
    • Abstract: Publication date: Available online 18 November 2019Source: Advances in Space ResearchAuthor(s): Philipp Oleynik, Rami Vainio, Hannu-Pekka Hedman, Arttu Punkkinen, Risto Punkkinen, Lassi Salomaa, Tero Säntti, Jarno Tuominen, Pasi Virtanen, Alexandre Bosser, Pekka Janhunen, Emilia Kilpua, Minna Palmroth, Jaan Praks, Andris Slavinskis, Syed R.U. Kakakhel, Juhani Peltonen, Juha Plosila, Jani Tammi, Hannu TenhunenAbstractThe Particle Telescope (PATE) of FORESAIL-1 mission is described. FORESAIL-1 is a CubeSat mission to polar Low Earth Orbit. Its scientific objectives are to characterize electron precipitation from the radiation belts and to observe energetic neutral atoms (ENAs) originating from the Sun during the strongest solar flares. For that purpose, the 3-unit CubeSat carries a particle telescope that measures energetic electrons in the nominal energy range of 80–800 keV in seven energy channels and energetic protons at 0.3–10 MeV in ten channels. In addition, particles penetrating the whole telescope at higher energies will be measured in three channels: one >800 keV electron channel, two integral proton channels at >10 MeV energies. The instrument contains two telescopes at right angles to each other, one measuring along the spin axis of the spacecraft and one perpendicular to it. During a spin period (nominally 15 s), the rotating telescope will, thus, deliver angular distributions of protons and electrons, at 11.25-degree clock-angle resolution, which enables one to accurately determine the pitch-angle distribution and separate the trapped and precipitating particles. During the last part of the mission, the rotation axis will be accurately pointed toward the Sun, enabling the measurement of the energetic hydrogen from that direction. Using the geomagnetic field as a filter and comparing the rates observed by the two telescopes, the instrument can observe the solar ENA flux for events similar to the only one so far observed in December 2006. We present the Geant4-simulated energy and angular response functions of the telescope and assess its sensitivity showing that they are adequate to address the scientific objectives of the mission.
       
  • Numerical Simulations of Water Spray on Flame Deflector During the
           Four-Engine Rocket Launching
    • Abstract: Publication date: Available online 16 November 2019Source: Advances in Space ResearchAuthor(s): Zhitan Zhou, Chenyu Lu, Changfang Zhao, Guigao LeAbstractThis paper aims to study on the cooling effect with two types of water spray nozzle on the flame deflector during the four-engine launch vehicle take-off. To accurately simulate the two-phase flow of the rocket gas with multispecies and the water spray, the three-dimensional compressible Navier-Stokes equations, discrete ordinates methods and realizable k-Ɛ turbulence model are used to establish the rocket supersonic plumes impact model. The Eulerian dispersed phase (EDP) model was used to simulate the water spray into the exhaust gas. The accuracy and effectiveness of the gas-liquid flow model are verified by a good agreement between simulation results and experimental data. On this basis, a series of numerical simulation studies under different water injection position are performed. The results show that the high temperature regions, along the axis of engines on the deflector plate, have no significant temperature decreasing effect by water spray from the nozzles mounted on the apex of the deflector, and the high temperature converts a large quantity of water into vapor near the plume boundary, which would decrease the flow conductivity. With the cooling spray nozzle fixed directly to the deflector plate, the temperature decrease effect is obvious and the effect of thermal shock on deflector plate induced by exhaust plume is reduced, so that it can prevent the flame deflector from thermal ablation. The study results provide indepth information and engineering guidance for designing the water spray systems and increasing the safety of the launch process.
       
  • Extending multipath hemispherical model to account for time-varying
           receiver code biases
    • Abstract: Publication date: Available online 15 November 2019Source: Advances in Space ResearchAuthor(s): Xiao Zhang, Baocheng Zhang, Yunbin Yuan, Jiuping ZhaAbstractMultipath effects on code observables account for one of the major error sources in high-accuracy Global Positioning System (GPS)-based positioning, atmosphere sounding and timing applications. The multipath hemispherical model (MHM) represents one of the most widely used methods of mitigating code multipath effects by taking advantage of their spatial repeatability. The use of MHM usually assumes that the receiver code biases (RCBs) are time-invariant; however, this assumption is not always valid, as RCBs and linear combinations thereof (differential code biases, for instance) have long been found to be time-varying over a period of one day. In this contribution, we propose an extended multipath hemispherical model (EMHM) that is capable of mitigating the code multipath effects in the presence of time-varying RCBs. Consequently, the proposed EMHM has two advantages. First, the EMHM gives rise to code multipath corrections with improved reliability because it addresses the intraday variability of RCBs. Second, more interestingly, the EMHM allows easy and effective calibration of short-term temporal variations, if any, in the RCB on each frequency. These advantages are hopeful to benefit GPS code-related applications.
       
  • Design of BDS-3 Integrity Monitoring and Preliminary Analysis of its
           Performance
    • Abstract: Publication date: Available online 12 November 2019Source: Advances in Space ResearchAuthor(s): Yueling Cao, Jinping Chen, Xiaogong Hu, Feng He, Lang Bian, Wei Wang, Bin Wu, Yang Yu, Jingyuan Wang, Qiuning TianAbstractWith the improvement in the service accuracy and expansion of the application scope of satellite navigation systems, users now have high demands for system integrity that are directly related to navigation safety. As a crucial index to measure the reliability of satellite navigation systems, integrity is the ability of the system to send an alarm when an abnormity occurs. The new-generation Beidou Navigation Satellite System (BDS-3) prioritized the upgrading of system integrity as an important objective in system construction. Because the system provides both basic navigation and satellite-based augmentation system (SBAS) services by the operational control system, BDS-3 adopts an integrated integrity monitoring and processing strategy that applies satellite autonomous integrity monitoring and ground-based integrity monitoring for both the basic navigation service and SBAS navigation service. BDS-3 also uses an improved and refined integrity parameter system to provide slow, fast and real-time integrity parameters for basic navigation, and provide SBAS-provided integrity information messages in accordance with Radio Technical Commission for Aeronautics (RTCA) specification and dual frequency, multi-constellation (DFMC) specification to support the SBAS signal frequency, single constellation operation and DFMC operation respectively. The performance of BDS-3 system integrity monitoring is preliminarily verified during on-orbit testing in different states, including normal operation, satellite clock failure and satellite ephemeris failure. The results show that satellite autonomous integrity monitoring, ground-based integrity monitoring and satellite-based augmentation all correctly work within the system. Satellite autonomous integrity monitoring can detect satellite clock failure but not satellite orbit failure. However, ground-based integrity monitoring can detect both. Moreover, the satellite-based augmentation integrity system monitors the differential range error after satellite ephemeris and clock error corrections based on user requirements. Compared to the near minute-level time-to-alert capability of ground-based integrity monitoring, satellite autonomous integrity monitoring reduces the system alert time to less than 4 seconds. With a combined satellite-ground monitoring strategy and the implementation of different monitoring technologies, the BDS-3 integrity of service has been considerably improved.
       
  • A Fast Chebyshev Polynomial Method for Calculating Asteroid Gravitational
           Fields using Space Partitioning and Cosine Sampling
    • Abstract: Publication date: Available online 11 November 2019Source: Advances in Space ResearchAuthor(s): Hongwei Yang, Shuang Li, Jun SunAbstractThis paper presents a computationally fast method for solving gravitational accelerations near irregularly-shaped asteroids. This method is based on analytical three-dimensional Chebyshev polynomial approximation of the polyhedral gravity. For the purpose of improving the approximation accuracy, space partitioning schemes based on practical flight zones is used to avoid interpolation the whole space around the target asteroid. Specifically, a minimum ellipsoid close to the asteroid surface is defined to select the space for surrounding trajectories with safe distance and a cone connected to the surface is defined to select the space for descent trajectories. Moreover, interpolation points are sampled in a cosine sampling fashion according to the Chebyshev-Gauss-Lobatto nodes and a radial adaption technique. The performance of different space partitioning schemes is analyzed. The effectiveness of the proposed method is validated through simulations of solving gravitational accelerations at the test points near different shaped asteroids 1996 HW1, 433 Eros, 25143 Itokawa and 101955 Bennu.
       
  • Evolution of an Electron Beam Pulse Influenced by Coulomb Collision
           Effects in the Solar Corona
    • Abstract: Publication date: Available online 9 November 2019Source: Advances in Space ResearchAuthor(s): G.A. Casillas-Pérez, S. Jeyakumar, A. Carrillo-Vargas, H.R. Pérez-EnríquezAbstractElectrons accelerated in the corona during solar activity give rise to radio emission events that can be observed over a wide range of frequencies. Among different finer-scale structures in the dynamic spectra observed in the radio range, fast transients with extents of some milliseconds known as solar radio spikes are observed accompaning the background continuum emission. Fundamental to the generation of radio spikes is a propagating electron beam and following its evolution allows us to understand the physical processes occurring in the solar corona. With the use of a numerical Fokker-Planck code we follow a previous numerical study to simulate the propagation of an electron beam pulse injected in a small region at the top of a magnetic field and outwards the solar corona under typical flare conditions. It was found that in large ambient densities of 1010 cm−3 at the injection point, Coulomb collision effects have an important effect on the propagation of the electrons, causing that the injected electrons thermalize faster in a time of 0.1 and 0.4 s for an electron distribution with a low-energy cut off of 16 and 7 keV respectively and a spectral index of 3. For a tenous ambient medium of density 109 cm−3 thermalization occurs only for an electron distribution with smaller low-energy cut off (7 keV) with a duration of ≈ 1.5 s, while for a larger low-energy cut off (16 keV) the loss of accelerated electrons is very slow, regardles of the spectral index (3,7). The electron loss time by Coulomb collisions, which depends on the low boundary ambient density, might be an important parameter that influences the generation of radio spikes due to the formation of instabilities in the corona.
       
  • Trends in foF2 and the 24th solar activity cycle
    • Abstract: Publication date: Available online 9 November 2019Source: Advances in Space ResearchAuthor(s): A.D. Danilov, A.V. KonstantinovaAbstractThe trends in foF2 are analyzed based on the data of Juliusruh and Boulder ionospheric stations. It is shown that using the traditional solar activity index F10.7 leads to an impossible trend in foF2 when the data for the 24th solar activity cycle are included into the analysis. It is assumed that the F10.7 index does not describe correctly the solar ultraviolet radiation variations in that cycle. A correction of this index using the Rz (sunspot number) and Ly (intensity of the Lyman-α line in the solar spectrum) is performed, and it is shown that in that case reasonable values of the foF2 trends are obtained.
       
  • Case studies: A possible mechanism for F2-lacuna formation
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Shenggao Yang, Beichen Zhang, Yang Liu, Yaguang Zhu, Xu Yang, Chao Tian, Fulu Yue, Peikang Xu, Jianming JiangAbstractTwo cases of F2-lacuna and their simultaneous ionospheric convection and TEC variations were presented to further understand F2-lacuna formation mechanism. Both cases of F2-lacuna are accompanied by decreased electron density and increased plasma flow. Through analyzing the role of convection electric field in the formation of F2-lacuna, an explanation for F2-lacuna formation was provided. The joule heating and frictional heating ascribed to the strengthened electric field causes the increase of electron and ion temperature, which subsequently, causes the enhancements of the recombination rate and the upflow of the O+ density resulting in decreased O+ density in F2 region.
       
  • Experimental investigation on location of debris impact source based on
           acoustic emission
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): E.L. Tang, Z.Q. Liang, L. Wang, Y.F. HanAbstractIn view of the objective reality that it takes a long time for debris to locate the impact point when debris impacts the spacecraft bulkhead, timely and accurate determination of the location of the impact source is the premise and basis for damage repair, which is of great significance to the safety of astronauts. In this paper, the experiments of 2A12 aluminium plate impacted by 2A12 aluminium projectile under different impact parameters have been performed by using the self-built acoustic emission testing system and two-stage light gas gun loading system. The calculated coordinates are compared with the experimental coordinates by using triangular positioning method, quadrilateral positioning method and acoustic emission (AE) signal processing method based on Wavelet transform. The experimental results show that the positioning accuracy of quadrilateral positioning method is better than that of triangular positioning method, and the acoustic emission signal processing method based on wavelet transform is obviously better than that of quadrilateral positioning method.
       
  • A new attitude integration algorithm for coning environment
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Lijuan Xiong, Hongtao Zhu, Weijun Wu, Bo ZhouAbstractAttitude determination of the space vehicle always plays a pivotal role in space missions. Usually, the fourth-order Runge Kutta algorithm is taken as more common attitude integration algorithm. However, more appropriate algorithms are desired in order to meet variable requirement. This paper investigates the performance of the fourth-order Runge Kutta and Taylor series algorithms in coning environment, and presents a new algorithm which takes advantages from above both. Series of simulation experiments have been conducted to verify the effect of the new algorithm. Their results show that the new algorithm outperforms the fourth-order Runge Kutta and the four-sample rotation vector algorithms over long-duration run even in complex engineering applications where the attitude change is not too fast.
       
  • Systematic low-thrust trajectory design to Mars based on a full Ephemeris
           modeling
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Mohammadreza Saghamanesh, Ehsan Taheri, Hexi BaoyinAbstractOne of the fundamental tasks in space mission design is to choose a set of inter-disciplinary mission-critical parameters that are used for both sizing spacecraft sub-systems and designing optimal trajectories. Trajectory design and sub-system sizing are tightly coupled tasks and mission designers are interested in algorithms that not only improve fidelity of the underlying models, but also facilitate comprehensive trade-off studies using dependable algorithms. This paper presents a systematic-design/computationally-efficient framework that makes use of a recently developed hybrid optimization method, which is a fusion between homotopic approach and particle swarm optimization to perform a robust homotopic approach. A salient feature of this framework is the flexibility in altering the fidelity of the dynamical models to beyond the conventional two-body model by including perturbations due to: (1) other planets of the Solar System, (2) solar radiation pressure, and (3) the oblateness effects of the Earth. Moreover, a comprehensive study on the impact of using different types of thrusters, different hyperbolic excess velocity values, and different launch opportunities is conducted. Extensive numerical simulations are performed for a heliocentric rendezvous mission from Earth to Mars and the results are compared against those in the literature.
       
  • Orbit determination of CE-4′s relay satellite in Earth-Moon L2
           libration point orbit
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Jianfeng Duan, Zhaokui WangAbstractThe Magpie Bridge mission is a part of the Chang’E-4 mission, it is the first Chinese spacecraft carries out Earth-Moon communication mission at Earth-Moon libration points. The Magpie Bridge operations team utilizes the Beijing Aerospace Control Center (BACC) Orbit Determination and Analysis Software (BODAS) to obtain the orbit, the measurements include range, Doppler and relay, relay-rate from China Deep Space Network (CDSN) and Very Long Baseline Interferometry (VLBI) system respectively. In order to effectively improve the accuracy of the orbit, we provided the solar radiation model with multiple characteristic surfaces. The new model is based on the structure and the real-time attitude of the satellite to solve the real-time solar pressure equivalent area. Compared with the cannon-ball model, it can calculate the solar pressure equivalent area of the satellite more accurately in orbit determination. By the analysis of the tracking measurement data, we found that the new solar radiation pressure model reduces the error of position and velocity compared to the cannon-ball model.
       
  • Indirect robust suboptimal control of two-satellite electromagnetic
           formation reconfiguration with geomagnetic effect
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Da-wei Qi, Le-ping Yang, Yuan-wen Zhang, Wei-wei CaiAbstractAs a novel approach to control the relative motion of a satellite formation, electromagnetic formation flight (EMFF) has some prominent advantages, such as no propellant consumption and no plume contamination, and has a broad prospect of application in such fields as on-orbit detection and optical interferometry. The current paper investigates the optimal control for the reconfiguration of a two-satellite electromagnetic formation using the nonlinear quadratic optimal control technique. Specifically, the effects of the Earth’s magnetic field on the EMFF satellites are analyzed, and then the nonlinear translational dynamic model of a two-satellite electromagnetic formation is derived by utilizing the analytical mechanics theory. Considering the high nonlinearity and coupling in the dynamic model and the actuator saturation, a closed-loop robust suboptimal control strategy based on the indirect robust control scheme and the θ-D technique is proposed with robust stability and optimality. To ensure a further reduction of control input, the designed suboptimal controller is modified by applying the Tracking-Differentiator. The feasibility of the derived translational dynamics and proposed control strategy for the robust reconfiguration mission is validated through theoretical analysis and numerical simulations.
       
  • Variability of NmF2 during solar minima at the Equatorial Ionization
           Anomaly crest region
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Madeeha Talha, Nabeel Ahmed, Muneeza M. Ali, Ghulam MurtazaAbstractThe variability of NmF2 during solar minima of solar cycle 21–22, 22–23 and 23–24 has been studied for two low latitude stations, Karachi (Pakistan) and Okinawa (Japan), as both stations are situated at the Equatorial Ionization Anomaly (EIA) crest region. Diurnal, seasonal and annual behaviour of variability has been investigated using relative standard deviation approach. At both the stations, a direct relation of variability (CV) with Smoothed Sunspot Numbers (SSN) is noted which is opposite to the results found by many authors who have worked on different solar activity periods. It is suggested that the E-layer is responsible for this direct relation as an increase in the E-layer ionization with decrease in SSN for solar minimum has also been noted for Karachi in our previous work (Talha et al., 2019). The interaction of tides and waves with the E-layer might be responsible for the increase in ionization of the E-layer and the decrease in variability in the F-layer. Also, the night-time variability is observed to be higher than the daytime variability during minima as expected due to the low mean NmF2 or large deviation during night-time. Very prominent post-midnight peaks and not very well shaped post-sunset peaks are also noticed at both stations. Besides the mentioned peaks, a small increase in variability during mid-day is noticed which might be due to the flow of fountain plasma from the equator to the EIA crest region. Seasonal comparison of variability showed high variability during daytime in winter and during night-time in equinox while lowest variability is noted in summer. Lowest variability at post-midnight is noted in winter instead of summer which might be due to the complex interaction of waves and tides with the lower ionosphere. Small difference in variability between both stations is also noticed due to difference in their longitude. Geomagnetic field configuration at both stations is different which in turn causes change in the electron density and also difference in variability at both stations.
       
  • Quantification of Sq parameters in 2008 based on geomagnetic observatory
           data
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Anatoly Soloviev, Artem Smirnov, Alexei Gvishiani, John Karapetyan, Anahit SimonyanAbstractThe paper presents an investigation of the time-dependent parameters of the solar quiet daily (Sq) variation for the minimum of the solar cycle 23/24 in 2008. We apply “Measure of Anomalousness” algorithm to detection of the magnetically quiet days. Global distribution of Sq amplitudes of the three orthogonal magnetic field components is analyzed using one-year data from 75 INTERMAGNET geomagnetic observatories and 46 SuperMAG stations. The study reveals strong latitudinal dependence of the Sq(X) amplitudes, which is approximated by the sixth-order polynomial trend curve. Sq(Y) amplitudes also suggest latitudinal dependence, while no significant difference is found in the Sq(Z) amplitudes across all latitudes. In the equatorial region, Sq(X) amplitudes are strongly affected by the equatorial electrojet (EEJ), having maxima during equinoctial seasons in the region of the South Atlantic magnetic anomaly (SAA). Sq(Y) demonstrates clear dependence on solar activity and amount of solar illumination, as the Sq(Y) amplitudes are typically greater in the summer-hemisphere and smaller in the winter-hemisphere. We analyze equivalent Sq current system using observatory data from the Australian mainland and narrow European-African latitudinal segment. Sq current system also strongly depends on solar activity, as the current vortices in the winter-hemisphere disintegrate showing no trace of Sq current loops’ formation, while the current vortices become evident in the summer-hemisphere.
       
  • Icing performance of stratospheric airship in ascending process
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Qiang Liu, Yanchu Yang, Qian Wang, Yanxiang Cui, Jingjing CaiAbstractThe critical applications of the stratospheric airship require all weather launch capabilities. When the airship flies across icy clouds and confronts super cooled droplets in the ascending process, there exist the risk of ice accretion on the windward parts of the airship. A three dimensional ice accretion model is proposed to simulate the icing performance of a stratospheric airship in ascending process. The mathematical equations describe the ice accretion model are presented and the validation of the ice accretion model is carried out. Then, the influence of the thermal environment on the thermal performance of the airship is analyzed numerically, and a further inspection into the icing performance of a stratospheric airship is conducted. The results suggest that ice would accrete on the windward surface of the airship under certain conditions, ice accretion will change the aerodynamic performance and break the lift and gravity balance of the airship, which would seriously deteriorate the flight performance of the airship.
       
  • The effect of different phases of severe geomagnetic storms on the low
           latitude ionospheric critical frequencies
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Erdinç TimoçinAbstractIn this paper, the effect of different phases of severe geomagnetic storms on low latitude ionospheric critical frequencies (foF2) is investigated. For this purpose, hourly ionospheric critical frequency (foF2) data measured at the low latitude ionosonde station Manila during 1981 and 1991 is examined. The investigation is carried out using superposed epoch analysis method considering the disturbance storm time index Dst ≤ −100 nT hours as event times. To examine depending on local time the effect of the phases of geomagnetic storms on foF2, this analysis was conducted for separately for the day hours, night hours, and all hours during both the main and the recovery phases of the severe geomagnetic storms and the results were compared with each other. It is observed that for both 1981 and 1991, the highest change (increase or decrease) in foF2 values occurs at the event times for all hours of day during both the main and the recovery phase of severe geomagnetic storms. Also, during the main phases of severe geomagnetic storms, the foF2 values increase at day hours, while the foF2 values decrease at night hours. However, during the recovery phases of severe geomagnetic storms, the foF2 values decrease at day hours, while the foF2 values increase at night hours. For both the day and night hours, the changes in the foF2 values during the recovery phase of severe geomagnetic storms are greater than the changes in the foF2 values during the main phase of severe geomagnetic storms.
       
  • Satellite based trend analysis of few atmospheric parameters over the
           Indian region
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Pooja Jindal, Pradeep Kumar Thapliyal, Munn Vinayak Shukla, Som Kumar Sharma, Debashis MitraAbstractThe present work has been carried to analyze the changes in trend of temperature, water vapor and ozone profiles at different atmospheric layers, total column integrated methane (TCH4) and total column integrated carbon-monoxide (TCO) over the Indian region. The atmospheric column was divided into few atmospheric layers: surface-850 hPa, 850–500 hPa, 500–100 hPa, 100–50 hPa and 50–1 hPa. Monthly averages of these parameters were calculated from AIRS Level 2 Standard Products for a decade from 2003 to 2012. A non-parametric statistical test with seasonal modification was applied to check the trends of various parameters. Monthly means were used to examine the seasonal dependency in the trend, and allowing more information from the data to be used. The layer average temperature in surface-850 hPa layer has shown significant increase in overall annual trend over eastern part, southern part and averaged over whole India with an increase of 0.041 K/year, 0.034 K/year and 0.034 K/year, respectively. The overall trend was decreasing over all but southern parts in 100–50 hPa layer at the rate of 0.079 K/year over whole India. For water vapor trends, it has been found that layer integrated water vapor (LIWV) in surface-850 hPa layer has significant overall increasing trend over western part, southern part and averaged over whole India with the rate of increase of 0.555%/year, 0.598%/year and 0.486%/year respectively. For LIWV (850–500 hPa), only western part has significant increasing trend at a rate of 0.879%/year. However, LIWV in 500–100 hPa layer does not show any significant trend. Total water vapor (TWV) has shown significant annual increasing trend over all the parts except over the central part. The increasing trend has been estimated as 0.962%/year over whole India. The layer integrated ozone (LIOZ) in surface-850 hPa has significant increasing trend over western part (0.062%/year) and southern part (0.071%/year). In 500–100 hPa layer, the LIOZ has statistically significant decreasing trend over whole India at a rate of 0.112%/year. For LIOZ averaged over whole India in 100–50 hPa, there is significant decreasing trend with a rate of 0.273%/year. Overall, the ozone concentration is increasing near surface, whereas it is decreasing in lower stratosphere. The total column ozone (TOZ) has not shown any significant trend. The column integrated methane has shown an increasing trend (0.366%/year) over all parts of the country, whereas, TCO has not shown any significant trend.
       
  • Mapping paddy rice by the object-based random forest method using time
           series Sentinel-1/Sentinel-2 data
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Yaotong Cai, Hui Lin, Meng ZhangAbstractRice is one of the world’s major staple foods, especially in China. In this study, we proposed an object-based random forest (RF) method for paddy rice mapping using time series Sentinel-1 and Sentinel-2 data. Firstly, the Robust Adaptive Spatial Temporal Fusion Model (RASTFM) was used to blend MODIS and Sentinel-2 data for achieving multi-temporal Sentinel-2 data. Subsequently, the Savitzky-Golay filter (S-G) was applied to smooth the time series Sentinel-2 NDVI data. And the phenological parameters were derived from the filtered time series NDVI using the threshold method. Then, the optimum feature combination for paddy mapping was formed on the basis of Sentinel-2 MSI images, time series Sentinel-2 NDVI, phenology data and time series Sentinel-1 SAR backscattering images by using the JBh distance. Finally, an object-based Random Forest classifier was used to extract paddy rice with the optimum feature combination. The result showed that fused Sentinel-2 NDVI time series using RASTFM has a high correlation with the original Sentinel-2 image. The overall accuracy and Kappa coefficient of the classification results are higher than 95% and 0.93, respectively, when use the optimum feature combination and object-based RF method. The proposed method can provide technology support for rice mapping in areas with a lot of cloudy and rainy weathers.
       
  • Sea-level rise and vertical land motion on the Islands of Oahu and Hawaii,
           Hawaii
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Linqiang Yang, Oceana Puananilei FrancisAbstractSea-level rise is a highly publicized issue in the Hawaiian Islands because it is one of the main drivers for coastal hazards. In our study, multiple geodetic and in situ datasets are integrated to investigate the sea-level rise and vertical land motion on the islands of Oahu and Hawaii, Hawaii. The rates of relative sea-level changes are derived from the tide-gauge stations in the Hawaiian Islands, however the station located at Kawaihae, Hawaii presents a much higher trend than other stations. Our analysis shows that the questionable trend results from the sudden movement of the equipment on land, which is caused by a pair of earthquakes. After adjustment, we arrive at a revised and more consistent relative sea-level trend at this station. Our study shows that Oahu is vertically ‘stable’ (i.e., near-zero vertical land movement within uncertainties), and the relative sea-level change is dominated by the absolute sea-level change. However, the island of Hawaii was subsiding at −3.3 ± 0.9 mm/year before 1973 and changed to −1.2 ± 0.2 mm/year after 1975, which may relate to seismic activities and where relative sea-level change is attributed to both absolute sea-level change and vertical land motion. The difference in relative sea-level change between the islands of Oahu and Hawaii is due to the difference in vertical land motion rather than steric sea-level change. In addition, the ocean-mass components are the predominant factors that influence the long-term trends of absolute sea level on the islands of Oahu and Hawaii.
       
  • A polar coordinate system based on a projection surface for moon-based
           earth observation images
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Lu Zhang, Huadong Guo, Hui Jiao, Guang Liu, Guozhuang Shen, Wenjin WuAbstractAs a new potential platform for Earth observation, the Moon which is a natural satellite unique to the Earth has been paid more and more attention for its consistent and continuous observation capability of global-scale and macroscopic geoscience phenomena on Earth. Because of the effect of Earth curvature and the Earth–Moon geometric relationship, the geometric correction of the Moon-based Earth observation (MBEO) hemisphere images is more complex than that required for images obtained from low Earth orbit (LEO) platforms and need to be investigated, such as optical images in visible/thermal infrared frequencies or synthetic aperture radar (SAR) images in microwave frequency. In addition, it is also difficult to find the uniformly distributed geometric correction control points on the entire surface of the Earth caused by sea and cloud cover in most regions. In this paper, a polar coordinate system on a projection surface related to the sublunar point is designed to facilitate the geometric correction of MBEO hemisphere images and to try to compensate for the problems of geometrical distortion caused by the shift of the sublunar point, the curvature of the Earth and the terrain fluctuation. Through simulation analysis, the geometric error characteristics and conditions in which the proposed moon-projection polar coordinate system can be used are discussed. This involves considering the Earth model, the projection method, the offset of the sublunar point and the external error. The results show the validity and adaptation of the proposed polar coordinate system and will support the further study of the geometric correction of MEBO images.
       
  • Estimating the slip rate on the north Tabriz fault (Iran) from InSAR
           measurements with tropospheric correction using 3D ray tracing technique
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s): Saeid Haji-Aghajany, Behzad Voosoghi, Yazdan AmerianAbstractIn this paper, interseismic deformation across the north Tabriz fault (NTF) using 17 ASAR/ENVISAT acquisitions on a single track for the period 2003–2010 have been investigated. One of the main limiting factors on the accuracy of interferometric synthetic aperture radar (InSAR) measurements comes from phase propagation delays through the troposphere. In order to retrieve millimeter velocities of interseismic deformations, it is necessary to improve the tropospheric corrections and correct interferograms. For this purpose, the 3D ray tracing technique based on eikonal equations has been used to estimate the tropospheric corrections. The corrected InSAR measurements are used to derive the interseismic displacement velocity field of the study area. The obtained velocity field has enabled us to accurately estimate the slip rate and locking depth for the NTF, using a simple elastic dislocation model. The numerical achievements show a slip rate of 5.6 ± 0.15 mm/yr below a locking depth of 14.5 ± 0.67 km for the NTF. Generally, the results of this paper are confirmed by the previous studies of the NTF parameters and some differences are due to this paper applied method for tropospheric corrections.
       
  • List of Referees
    • Abstract: Publication date: 1 December 2019Source: Advances in Space Research, Volume 64, Issue 11Author(s):
       
 
 
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