Frontiers in Astronomy and Space Sciences最新文献

{"title":"Solitary wave characteristics on the fine structure of the mesospheric sporadic sodium layer","authors":"Shican Qiu, Mengxi Shi, Hamad Yousof, Willie Soon, Mingjiao Jia, Xianghui Xue, Tao Li, Peng Ju, Xiankang Dou","doi":"10.3389/fspas.2023.1241663","DOIUrl":"https://doi.org/10.3389/fspas.2023.1241663","url":null,"abstract":"The so-called sporadic sodium layers (SSLs or Na S ) are proposed to be strongly related to wave fluctuations. The solitary wave is a particular solution of the partial differential equation whose energy travels as a localized wave packet. A soliton, on the other hand, is a special type of solitary wave that exhibits a particle-like behavior with a strong stable form. For the first time, the solitary wave theory has been used in this research to study the fine structure of SSL/Na S . We performed soliton fitting processes on the observed data from the Andes Lidar Observatory and found out that 24/27 Na S events had exhibited similar features/characteristics to a soliton. Time series of the net anomaly of the Na S revealed the same variation process to the solution of a generalized five-order KdV equation. Our results, therefore, suggested that the Na S phenomenon would be a pertinent tracer for non-linear wave studies in the atmosphere.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135884356","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"How Tycho Brahe’s recordings in 1572 support SN 1572 as a type I(a) supernova","authors":"Tobias C. Hinse, Bertil F. Dorch, Lars V. T. Occhionero, Jakob P. Holck","doi":"10.3389/fspas.2023.1255481","DOIUrl":"https://doi.org/10.3389/fspas.2023.1255481","url":null,"abstract":"The 450th anniversary of the discovery of the SN 1572 supernova event was celebrated in 2022. A closer look at the historical development of the field of supernova astronomy reveals the scientific importance of Tycho Brahe’s 1572 observations of this “new star.” In their quest to learn more about the new type of stellar explosion and subsequent evolution, the initial protagonists in this field (Baader and Zwicky among others) gradually turned their attention to the final remnant state of these supernova events. Since the remnant object thought to be associated with the extragalactic supernova event was found to be very dim, the focus quickly shifted toward nearby galactic events. It is at this point where Tycho Brahe’s observations played an important and often overlooked role in the context of the development of stellar evolution as a scientific field. Tycho Brahe’s meticulous and detailed recordings of the change in brightness of the new star not only allowed modern astronomers to classify SN 1572 as a supernova event but also helped them pinpoint the exact astrometric location of SN 1572. These findings helped to empirically link extragalactic supernova events to nearby past supernova remnants in the Milky Way. This enabled subsequent observations allowing further characterization. Transforming the historical recordings to a standardized photometric system also allowed the classification of SN 1572 as a type I supernova event.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135885923","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Exploring the impact of imaging cadence on inferring CME kinematics","authors":"Nitin Vashishtha, Satabdwa Majumdar, Ritesh Patel, Vaibhav Pant, Dipankar Banerjee","doi":"10.3389/fspas.2023.1232197","DOIUrl":"https://doi.org/10.3389/fspas.2023.1232197","url":null,"abstract":"The kinematics of coronal mass ejections (CMEs) are crucial for understanding their initiation mechanism and predicting their impact on Earth and other planets. With most of the acceleration and deceleration occurring below 4 R ⊙ , capturing this phase is vital to better understand their initiation mechanism. Furthermore, the kinematics of CMEs in the inner corona ( <mml:math xmlns:mml=\"http://www.w3.org/1998/Math/MathML\" id=\"m1\"><mml:mo><</mml:mo></mml:math> 3 R ⊙ ) are closely related to their propagation in the outer corona and their eventual impact on Earth. Since the kinematics of CMEs are mainly probed using coronagraph data, it is crucial to investigate the impact of imaging cadence on the precision of data analysis and the conclusions drawn from it and also for determining the flexibility of designing observational campaigns with upcoming coronagraphs. This study investigates the impact of imaging cadence on the kinematics of ten CMEs observed by the K-Coronagraph of the Mauna Loa Solar Observatory. We manually track the CMEs using high cadence (15 s) white-light observations of K-Cor and vary the cadence as 30 s, 1, 2, and 5 min to study the impact of cadence on the kinematics. We also employed the bootstrapping method to estimate the confidence interval of the fitting parameters. Our results indicate that the average velocity of the CMEs does not have a high dependence on the imaging cadence, while the average acceleration shows significant dependence on the same, with the confidence interval showing significant shifts for the average acceleration for different cadences. The impact of degraded cadence is also seen in the estimation of the time of onset of acceleration. We further find that it is difficult to find an optimum cadence to study all CMEs, as it is also influenced by the pixel resolution of the instrument and the speed of the CME. However, except for very slow CMEs (speeds less than 300 km −1 ), our results indicate a cadence of 1 min to be reasonable for the study of their kinematics. The results of this work will be important in the planning of observational campaigns for the existing and upcoming missions that will observe the inner corona.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135886378","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Evaluating the performance of empirical models of total electron density and whistler-mode wave amplitude in the Earth’s inner magnetosphere","authors":"Qianli Ma, Xiangning Chu, Donglai Ma, Sheng Huang, Wen Li, Jacob Bortnik, Xiao-Chen Shen","doi":"10.3389/fspas.2023.1232702","DOIUrl":"https://doi.org/10.3389/fspas.2023.1232702","url":null,"abstract":"Empirical models have been previously developed using the large dataset of satellite observations to obtain the global distributions of total electron density and whistler-mode wave power, which are important in modeling radiation belt dynamics. In this paper, we apply the empirical models to construct the total electron density and the wave amplitudes of chorus and hiss, and compare them with the observations along Van Allen Probes orbits to evaluate the model performance. The empirical models are constructed using the Hp30 and SME (or SML) indices. The total electron density model provides an overall high correlation coefficient with observations, while large deviations are found in the dynamic regions near the plasmapause or in the plumes. The chorus wave model generally agrees with observations when the plasma trough region is correctly modeled and for modest wave amplitudes of 10–100 pT. The model overestimates the wave amplitude when the chorus is not observed or weak, and underestimates the wave amplitude when a large-amplitude chorus is observed. Similarly, the hiss wave model has good performance inside the plasmasphere when modest wave amplitudes are observed. However, when the modeled plasmapause location does not agree with the observation, the model misidentifies the chorus and hiss waves compared to observations, and large modeling errors occur. In addition, strong (&amp;gt;200 pT) hiss waves are observed in the plumes, which are difficult to capture using the empirical model due to their transient nature and relatively poor sampling statistics. We also evaluate four metrics for different empirical models parameterized by different indices. Among the tested models, the empirical model considering a plasmapause and controlled by Hp* (the maximum Hp30 during the previous 24 h) and SME* (the maximum SME during the previous 3 h) or Hp* and SML has the best performance with low errors and high correlation coefficients. Our study indicates that the empirical models are applicable for predicting density and whistler-mode waves with modest power, but large errors could occur, especially near the highly-dynamic plasmapause or in the plumes.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135982329","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nuclear data for space exploration","authors":"Michael S. Smith, Ramona L. Vogt, K. Label","doi":"10.3389/fspas.2023.1228901","DOIUrl":"https://doi.org/10.3389/fspas.2023.1228901","url":null,"abstract":"Understanding the harmful effects of galactic cosmic rays (GCRs) on space exploration requires a substantial amount of nuclear data. Specifically, the interaction of energetic GCR charged particles with spacecraft materials generates secondary radiations that, through energy deposition, can harm astronauts and electronic systems. By identifying the gaps in our knowledge of the relevant nuclear data—such as interaction cross sections—and identifying ways to fill those gaps—with measurements, compilations, evaluations, dissemination, reaction modeling, sensitivity studies, and uncertainty quantification—the safety and viability of space exploration can be improved. This work surveys the state of the art in this interdisciplinary field and identifies promising collaborative research topics that have significant potential to advance our understanding of the effects of the space radiation environment on space exploration.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48230849","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The reaction rate of radiative n8Li capture in the range from 0.01 to 10 T9","authors":"S. Dubovichenko, B. Yeleusheva, N. Burkova, A. Tkachenko","doi":"10.3389/fspas.2023.1251743","DOIUrl":"https://doi.org/10.3389/fspas.2023.1251743","url":null,"abstract":"Within the modified potential cluster model (MPCM) with forbidden states, the total cross sections are calculated for capture in the ground and first excited states of the 9Li nucleus in the n8Li channel in the energy range from 10−5 eV to 5 MeV based on Е1 and M1 transitions. The experimentally proved resonance at Ec.m. = 0.232 MeV in the 4P5/2 wave and ab initio-predicted 4P3/2 resonance at 1.32 MeV [Phys. Rev. C 103, 035801 (2021)] are considered. The strong impact of the asymptotic constant and channel spectroscopic factors on the total capture cross sections are responsible for the variation in the absolute values within factor two. As a consequence, the thermal cross sections are σtherm= 24–46.8 mb. The evaluation of σtherm based on the extrapolation of ab initio cross sections yields ∼85 mb. The reaction rate is calculated in the temperature range from 0.01 to 10 T9. The reported reaction rates are compared at the benchmark point 1 T9. The comparison of two datasets [Phys. Rev. C 103, 035801 (2021) and Phys. Rev. C 105, 064608 (2022)] on reaction rates recently calculated in microscopic models in extended temperature intervals shows the essential quantitative and qualitative differences. The comparative joint analysis of the reaction rates of radiative neutron capture on the lithium isotopes 6,7,8Li is suggested for the choice of an optimal interval for the asymptotic constants.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48220459","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Prospect for measurements of (γ, n) reaction cross-sections of p-nuclei at ELI-NP","authors":"P. Söderström, A. Kuşoğlu, D. Testov","doi":"10.3389/fspas.2023.1248834","DOIUrl":"https://doi.org/10.3389/fspas.2023.1248834","url":null,"abstract":"The gamma beam system under construction at the ELI-NP facility in Romania is projected to give the nuclear physics community access to an experimental system providing a high-intensity, narrow bandwidth photon beam at variable energy. With high-efficiency detector systems in place, the experimental programme will have a strong potential for in-depth studies of rare stable isotopes originating from the astrophysical p-process. In particular, the neutron detection systems are already implemented through a dedicated 3He long neutron counter array, called ELIGANT-TN, that is completed and in use. In this mini-review, we will give a summary of the current status of existing (γ, n) cross-section data, as well as the methods to obtain them, and highlight the future potential to expand and improve such data using the ELI-NP instrumentation and beam-lines.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42470452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Challenges and interpersonal dynamics during a two-person lunar analogue Arctic mission","authors":"Pedro Marques-Quinteiro, Andres Käosaar, Paola Barros Delben, Anders Kjærgaard, G. R. Leon","doi":"10.3389/fspas.2023.1184547","DOIUrl":"https://doi.org/10.3389/fspas.2023.1184547","url":null,"abstract":"Introduction: This case study was designed as an analog for aspects of NASA’s planned Artemis missions to the lunar surface. The specific aims were to examine emerged mission challenges and dyadic affective and process dynamics over the course of a three-month lunar habitat analog Arctic mission.Methods: Participants were two men who also had key roles in designing the habitat. Pre- and post- expedition interviews were conducted and daily satellite phone messages to mission control over the three-month mission were assessed. An integrated mixed methods approach was used to analyze challenges, group affect, and group processes, with the goal of furthering the understanding of coping and psychosocial work experiences in challenging conditions.Results: The findings indicated that different challenges took distinct temporal trajectories across mission phases; based on the relational themes, several challenges were identified, primarily physical challenges related to the experience of coping in an ICE environment, and psychosocial challenges associated with the preparation and execution of mission tasks. Physical challenges, positive tone, and action processes were the themes most connected to each other. To deal with these challenges, the team adapted by more frequently engaging in action and transition processes. The specific training for the mission the participants engaged in, and prior knowledge about each other enabled team members to deal with mission exigencies while maintaining a positive outlook.Discussion: Fostering strong positive relationships was an important mechanism to build resilience and effective performance while under ongoing, extreme conditions.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44848458","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A system science methodology develops a new composite highly predictable index of magnetospheric activity for the community: the whole-Earth index E(1)","authors":"J. Borovsky, Christian J. Lao","doi":"10.3389/fspas.2023.1214804","DOIUrl":"https://doi.org/10.3389/fspas.2023.1214804","url":null,"abstract":"For community use, a new composite whole-Earth index E(1) and its matching composite solar wind driving function S(1) are derived. A system science methodology is used based on a time-dependent magnetospheric state vector and a solar wind state vector, with canonical correlation analysis (CCA) used to reduce the two state vectors to the two time-dependent scalars E(1)(t) and S(1)(t). The whole-Earth index E(1) is based on a diversity of measures via six diverse geomagnetic indices that will be readily available in the future: SML, SMU, Ap60, SYMH, ASYM, and PCC. The CCA-derived composite index has several advantages: 1) the new “canonical” geomagnetic index E(1) will provide a more powerful description of magnetospheric activity, a description of the collective behavior of the magnetosphere–ionosphere system. 2) The new index E(1) is much more accurately predictable from upstream solar wind measurements on Earth. 3) Indications are that the new canonical geomagnetic index E(1) will be accurately predictable even when as-yet-unseen extreme solar wind conditions occur. The composite solar wind driver S(1) can also be used as a universal driver function for individual geomagnetic indices or for magnetospheric particle populations. To familiarize the use of the new index E(1), its behavior is examined in different phases of the solar cycle, in different types of solar wind plasma, during high-speed stream-driven storms, during CME sheath-driven storms, and during superstorms. It is suggested that the definition of storms are the times when E(1) >1.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":" ","pages":""},"PeriodicalIF":3.0,"publicationDate":"2023-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47988573","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The importance of recruitment and retention in Heliophysics: it’s not just a pipeline problem","authors":"Alexa J. Halford, Christopher M. Bard, Angeline G. Burrell, Ryan M. McGranaghan, Lynn B. Wilson III, McArthur Jones, Chuanfei Dong, Liang Wang, Tuija I. Pulkkinen, Niescja Turner, Michael W. Liemohn, Jeff Klenzing","doi":"10.3389/fspas.2023.1216449","DOIUrl":"https://doi.org/10.3389/fspas.2023.1216449","url":null,"abstract":"A major obstacle in cultivating a robust Heliophysics (and broader scientific) community is the lack of diversity throughout science, technology, engineering, and mathematics (STEM) fields. For many years, this has been understood as a “leaky pipeline” analogy, in which predominately minority students initially interested in STEM gradually fall (or are pushed) out of the field on their way to a scientific research position. However, this ignores critical structural and policy issues which drive even later career Ph.D.s out of a career in Heliophysics. We identify here several systemic problems that inhibit many from participating fully in the Heliophysics community, including soft money pressure, lack of accessibility and equity, power imbalances, lack of accountability, friction in collaboration, and difficulties in forming mentorship bonds. We present several recommendations to empower research-supporting organizations to help create a culture of inclusion, openness, and innovative science.","PeriodicalId":46793,"journal":{"name":"Frontiers in Astronomy and Space Sciences","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2023-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135286357","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}