Astrophysics and Space Science最新文献

{"title":"Analysing orbits around the Moon for the Garatéa-L Mission","authors":"Giulliano Assis Sodero Boaventura,&nbsp;Silvia Maria Giuliatti Winter","doi":"10.1007/s10509-024-04297-4","DOIUrl":"10.1007/s10509-024-04297-4","url":null,"abstract":"<div><p>Recently, we have seen a series of space missions to the Moon and asteroids, whether for exploratory or scientific purposes, with possibilities of a lot of profitability in a sustainable way. Given this scenario, the Garatéa-L Mission (from the Brazilian original people language Tupi-Guarani, “Search for Life”) stands out, a genuinely Brazilian mission, whose main objective is to place a 6U brazilian cubeSat in orbit around the Moon, in 2024 or 2025, with the aim of carrying out experiments in astrobiology and studying the Aitken Basin, a basin located at the lunar south pole. In this context, the main goal of the present work is to study the orbits that meet the needs of the mission, obeying the necessary parameters of 300 km of periselene and 3000 km of aposelene. The system is formed by the Moon (the central body) and its gravitational coefficients, <span>(J_{2})</span>, <span>(J_{3})</span> and <span>(C_{22})</span>, the Earth as the perturbing body and a particle (cubesat). As a result, we obtained a sample of orbits that meets the requirements of the mission, their lifetimes in the region of interest and the evolution of the semi-major axis and eccentricity for each value of the inclination analysed. The results showed that the largest number of orbits with the longest lifetime have inclinations of 60° and 65°, with a semi-major axis of 3460 km and an eccentricity of approximately 0.38, remaining in the mission’s region of interest for an approximate period of 180 days.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140565099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Alfvén resonance on Kelvin-Helmholtz vortices at the Earth’s magnetopause","authors":"Yang Yang,&nbsp;HuaXuanYu Yuan,&nbsp;JiaQi Wang,&nbsp;Saleem Khan","doi":"10.1007/s10509-024-04294-7","DOIUrl":"10.1007/s10509-024-04294-7","url":null,"abstract":"<div><p>The Alfvén resonance is an extensively observed phenomenon in astrophysics, playing a crucial role in understanding energy transfer, macroscopic structure, and evolutionary processes within celestial environments such as the magnetospheres of stars, planets, and other astrophysical objects. In this work, we investigate the spatial and temporal distribution of the Alfvén resonance points during the evolution of Kelvin-Helmholtz instability (KHI) at Earth’s dusk-flank magnetopause in numerical MHD simulation. The results show that, there is no appearance of the Alfvén resonance points <span>(P_{AR})</span> during the linear phase. In the early nonlinear phase, the Alfvén resonance points <span>(P_{AR})</span>, whose duration time is approximately <span>(Delta {t_{1}} sim 3{t_{A}})</span>, looks like the “eyelid” of the KH vortex. During the nonlinear growth phase, the Alfvén resonance points <span>(P_{AR})</span>, whose duration time is about <span>(Delta {t_{2}} sim 6{t_{A}})</span>, appear at both the “eyelid” and the outer “corner” of the KH vortex. The Alfvén resonance phenomenon disappears with the decay of KH vortex.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-04-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140565231","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Quark stars in the pure pseudo-Wigner phase","authors":"Li-Qun Su,&nbsp;Chao Shi,&nbsp;Yong-Feng Huang,&nbsp;Yan Yan,&nbsp;Cheng-Ming Li,&nbsp;Wen-Li Yuan,&nbsp;Hong-Shi Zong","doi":"10.1007/s10509-024-04296-5","DOIUrl":"10.1007/s10509-024-04296-5","url":null,"abstract":"<div><p>In this paper, we consider the scenario of a pure quark star which is completely composed of quarks in the pseudo-Wigner phase. The equation of state (EoS) of deconfined quark stars is studied in the framework of the two-flavor NJL model, and the self-consistent mean field approximation is employed by introducing a parameter <span>(alpha )</span> combining the original Lagrangian and the Fierz-transformed Lagrangian, <span>(mathcal{L}_{R}= (1-alpha )mathcal{L}+alpha mathcal{L}_{F})</span>, to measure the weights of different interaction channels. We assume deconfinement phase transition happens along with the chiral phase transition. Thus, due to the lack of description of confinement in the NJL model, the vacuum pressure is set to confine quarks at low densities, which is the pressure corresponding to the critical point of chiral phase transition. We find that the bag constant shifts from <span>((130text{ MeV})^{4})</span> to <span>((150 text{ MeV})^{4})</span> as <span>(alpha )</span> grows. When <span>(alpha )</span> is around 0.9, the mass-radius relations of deconfined quark stars can meet the requirement of pulsar observations. In addition, the tidal deformability <span>(Lambda )</span> is found to range in 253 – 482, which satisfies the astronomical constraint of <span>(Lambda &lt;800)</span> for 1.4-solar-mass neutron stars.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-03-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140402115","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Spin-orbit coupling dynamics in a planar synchronous binary asteroid","authors":"Bo-Sheng Li,&nbsp;Pan Tan,&nbsp;Xi-Yun Hou","doi":"10.1007/s10509-024-04291-w","DOIUrl":"10.1007/s10509-024-04291-w","url":null,"abstract":"<div><p><b>Purpose:</b> The 1:1 spin-orbit resonance phenomenon is widely observed in binary asteroid systems. We aim to investigate the intrinsic dynamic mechanism behind the phenomenon under the coupled influence of the secondary’s rotation and orbital motion. <b>Methods:</b> The planar sphere–ellipsoid model is used to approximate the synchronous binary asteroid. The Lindstedt–Poincaré method is applied on the spin-orbit problem to find its explicit quasi-periodic solution. <b>Results:</b> Numerical simulations demonstrate that analytical solutions truncated at high orders are accurate enough to describe the orbital and rotational motions of the synchronous binary asteroid. With the help of the solution, we are able to identify in a more accurate way the stable region for the synchronous state by using the Lyapunov characteristic exponent. Moreover, the resonances that determine the boundary of the stability region are identified. <b>Conclusion:</b> The stable synchronous state requires a small eccentricity <span>(e)</span> of the mutual orbit but permits a large libration angle <span>(theta )</span> of the secondary. The anti-correlation of <span>(theta )</span> and <span>(e)</span> is confirmed. The stable region for a very elongated secondary is small, which helps explain the lack of such secondaries in observations (see Table 1 in Pravec et al. in Icarus 267:267–295, 2016). Findings of this study provide insights into the inherent dynamics that determine the rotational states of a synchronous binary asteroid.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140155569","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Prediction of ionospheric TEC by LSTM and OKSM during M class solar flares occurred during the year 2023","authors":"R. Mukesh,&nbsp;Sarat C. Dass,&nbsp;M. Vijay,&nbsp;S. Kiruthiga,&nbsp;Vijanth Sagayam","doi":"10.1007/s10509-024-04290-x","DOIUrl":"10.1007/s10509-024-04290-x","url":null,"abstract":"<div><p>Advancements in space weather forecasting have become crucial for understanding and mitigating the impacts of solar activity on Earth’s ionosphere. This research focuses on the prediction of Total Electron Content (TEC) during M-class solar flare events in 2023. TEC is a vital parameter for satellite communications and navigation, making accurate forecasting imperative. Two prediction models, Long Short-Term Memory (LSTM) neural networks and Surrogate Models based on Ordinary Kriging (OKSM), are employed. LSTM, known for capturing temporal dependencies, is contrasted with OKSM, a geostatistical interpolation technique capturing spatial autocorrelation. The study utilizes TEC measurements from the Hyderabad (HYDE) GPS station for model training and evaluation along with solar and geomagnetic parameters. The performance metrics for both models across various solar flare dates are measured using Root Mean Square Error (RMSE), Normalized RMSE, Correlation Coefficient (CC), and Symmetric Mean Absolute Percentage Error(sMAPE). The research interprets the results, highlighting the strengths and limitations of each model. Notable findings include LSTM’s proficiency in capturing temporal variations and OKSM’s unique spatial perspective. Different solar flare intensities are analyzed separately, demonstrating the model’s adaptability to varying space weather conditions. The average performance metrics during M 4.65 SF events for the OKSM model, in terms of Root Mean Square Error is 5.61, Normalized RMSE is 0.14, Correlation Coefficient is 0.9813, and Symmetric Mean Absolute Percentage Error is 14.90. Similarly, for LSTM, the corresponding averages are 10.03, 0.24, 0.9313, and 28.64. The research contributes valuable insights into the predictive capabilities of LSTM and OKSM for TEC during solar flare events. The outcomes aid in understanding the applicability of machine learning and geostatistical techniques in space weather prediction. As society’s reliance on technology susceptible to space weather effects grows, this research is pivotal for enhancing space weather forecasts and ensuring the robustness of critical technological infrastructure on Earth.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140128056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"An optimal deployment strategy for multi-plane satellite constellation using a generalized non-planar maneuver","authors":"Majid Bakhtiari,&nbsp;Ehsan Abbasali","doi":"10.1007/s10509-024-04288-5","DOIUrl":"10.1007/s10509-024-04288-5","url":null,"abstract":"<div><p>Satellite constellation deployment is a cohesive mission where the trajectories of satellites must be planned concurrently. This paper presents an Integrated Program for Optimal Deployment of a Satellite Constellation (PODSC) consisting of <span>(m)</span> non-identical satellites in any desired arrangement in <span>(n)</span> orbital planes. The PODSC can optimize the scheduling of mission timelines, ensuring effective coordination with the trajectory of each satellite. This involves meticulous planning that considers temporal constraints and regards collision avoidance constraint. Additionally, the PODSC can select the most favorable deployment strategy, considering the trade-offs between time and fuel consumption across all possible deployment methods. The PODSC also utilizes an innovative Perturbed Multi-impulsive Inclined transfer trajectory Amalgamated with a modified Lambert targeting problem (PMIAL). The main idea of designing the mentioned maneuver is to eliminate the defects of the Lambert Targeting Problem (LTP). The LTP cannot account for space perturbations. Moreover, the LTP faces challenges when attempting to align the transfer trajectory tangentially with the final orbit in situations where there exists a substantial disparity in inclination and right ascension between the initial and final orbits. The PMIAL establishes three consecutive steps to fix the mentioned defects. Balancing the trade-off between time and achieving optimal fuel consumption will be possible by applying a hybrid IWO/PSO (The hybrid Invasive Weed Optimization/Particle Swarm Optimization) optimization algorithm in both PMIAL and PODSC. The case study will involve simulating two constellation deployment missions, with a particular focus on considering the Earth’s oblateness as a notable perturbation; however, the proposed algorithms can consider any space perturbations.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-03-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140070140","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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 perturbative approach to complexity during dissipative collapse","authors":"Megandhren Govender,&nbsp;Robert S. Bogadi,&nbsp;Wesley Govender,&nbsp;Narenee Mewalal","doi":"10.1007/s10509-024-04287-6","DOIUrl":"10.1007/s10509-024-04287-6","url":null,"abstract":"<div><p>Radiative gravitational collapse is an important and much studied phenomenon in astrophysics. Einstein’s theory of general relativity (GR) is well suited to describing such processes provided closure of the system of nonlinear differential equations is achieved. Within a perturbative scheme, the property of vanishing complexity factor is used in order to complete the description of the radiative, self-gravitating system. We show that a physically viable model may be obtained which reflects the absence of energy inhomogeneities for lower density systems, in contrast to what might be expected for more aggressive collapse processes.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10509-024-04287-6.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140034761","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Correction to: Investigation of states switch properties of PSR J1946 + 1805 with the FAST","authors":"Jie Tian,&nbsp;Xin Xu,&nbsp;Juntao Bai,&nbsp;Jiguang Lu,&nbsp;Lunhua Shang,&nbsp;Shi Dai,&nbsp;Dandan Zhang,&nbsp;Guojun Qiao,&nbsp;Rushang Zhao,&nbsp;Aijun Dong,&nbsp;Wenqian Zhong,&nbsp;Qijun Zhi,&nbsp;Shijun Dang","doi":"10.1007/s10509-024-04289-4","DOIUrl":"10.1007/s10509-024-04289-4","url":null,"abstract":"","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140273508","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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":"Wrong hypotheses in the generalized RTBP","authors":"Antonio Elipe","doi":"10.1007/s10509-024-04286-7","DOIUrl":"10.1007/s10509-024-04286-7","url":null,"abstract":"<div><p>Generalized restricted three body problems consist of adding some extra hypotheses to the Restricted three body problem (RTBP) in order to have a new problem, not very different of the original RTBP. However, not any additional hypothesis is allowed; it must satisfy the laws of Physics. Among the several generalizations found in literature, we prove that at least there are two hypotheses that cannot be used, namely: 1) Perturbation in Coriolis and/or centrifugal forces, and 2) primaries are spheroids moving on elliptical orbits.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10509-024-04286-7.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139947043","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A review of 70 years with astrometry","authors":"Erik Høg","doi":"10.1007/s10509-024-04285-8","DOIUrl":"10.1007/s10509-024-04285-8","url":null,"abstract":"<div><p>In 1953 I heard of an experiment in 1925 by Bengt Strömgren where he observed transit times with the meridian circle at the Copenhagen University Observatory measuring the current in a photocell behind slits when a star was crossing. In 1954 just 22 years old I was given the task as a student to make first test observations with a new meridian circle of the observatory. I became fascinated by the instrument and by the importance of astrometry for astronomy. Work at four meridian circles, two in Denmark, one in Hamburg, one in Lund, and Pierre Lacroute’s vision of space astrometry in France had by 1973 created the foundation for development of the Hipparcos satellite, and Gaia followed. In 2013 I proposed a successor satellite which has gained momentum especially thanks to the efforts of David Hobbs and it has a good chance to be launched by ESA about 2045. – But 70 years ago, optical astrometry was considered a dying branch of astronomy, unattractive compared with astrophysics. The following growth built on the still active interest in astrometry in Europe in those years and it was supported by ESA, the European Space Agency. – This review is only about astrometry where I was personally involved.</p></div>","PeriodicalId":8644,"journal":{"name":"Astrophysics and Space Science","volume":null,"pages":null},"PeriodicalIF":1.8,"publicationDate":"2024-02-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139947146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"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}