Article
Astronomy & Astrophysics
P. Vemareddy
Summary: Magnetic helicity is a measure of twist and shear of magnetic field, and understanding the nature and evolution of photospheric helicity flux transfer is crucial in revealing the intensity of flare and coronal mass ejection activity. Through studying time-sequence vector magnetograms, it is found that injection of magnetic helicity with different signs can lead to magnetic field reconnection, resulting in intermittent flares and enhanced coronal heating.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Q. M. Zhang
Summary: This paper aims to track the three-dimensional evolution of a full halo coronal mass ejection (CME) and uses a revised cone model to derive its morphological and kinematic properties. The results show that the revised cone model fits nicely with the observed CME and the CME exhibits changes in angle and distance over time.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
S. N. A. Syed Zafar, R. Umar, N. H. Sabri, M. H. Jusoh, A. N. Dagang, A. Yoshikawa
Summary: Previous studies have shown that solar activities such as coronal mass ejections and solar flares can lead to the development of storms and high-speed streams. This study investigates the response of the geomagnetic index SYM/H to solar wind parameters, as well as the ground geomagnetic field responses at low-latitude stations. Findings suggest delayed response of the Earth's magnetosphere to weak geomagnetic storms, while strong solar wind and IMF variations can excite the Earth's H-component during geomagnetic storms caused by solar activities.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
Syed Ibrahim, Wahab Uddin, Bhuwan Joshi, Ramesh Chandra, Arun Kumar Awasthi
Summary: This study compared the properties of two coronal mass ejections (CMEs) and discussed their differences in near-Sun characteristics, interplanetary evolution, and geoeffectiveness. By analyzing the initiation and propagation parameters, the precise CME-ICME connection and their impact on Earth were established. The source region evolution of CMEs and their near-Sun propagation characteristics, such as CME-CME interactions, played important roles in determining their evolution in the interplanetary medium and subsequent geoeffectiveness.
RESEARCH IN ASTRONOMY AND ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Aiying Duan, Chaowei Jiang, Yue Guo, Xueshang Feng, Jun Cui
Summary: Solar eruptions are often caused by the complex magnetic environment in solar active regions. This study focuses on the magnetic field structure and evolution responsible for a major flare eruption in a complex active region. The study analyzes observations from the SDO and coronal magnetic field extrapolations. The findings suggest that the motions of the sunspots along a large-scale magnetic flux rope gradually built up the instability that led to the eruption. Localized reconnections also played a key role in the formation of the unstable magnetic flux rope.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Xinping Zhou, Yuandeng Shen, Zehao Tang, Chengrui Zhou, Yadan Duan, Song Tan
Summary: This study investigates the driving mechanisms and total reflection effect of a flare-driven quasi-periodic extreme ultraviolet wave train reflected at a coronal hole boundary, using observations from AIA/SDO.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Alexander W. James, David R. Williams, Jennifer O'Kane
Summary: This study aims to quantify the variation of critical height for torus instability-driven CMEs over time in solar active regions, and finds that the rate of CMEs is significantly higher when the critical height is increasing during phases of magnetic flux increase. Additionally, the critical height is generally proportional to the separation of magnetic polarities in the active regions.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
D. E. Morosan, J. Pomoell, A. Kumari, E. K. J. Kilpua, R. Vainio
Summary: The Sun produces powerful solar flares and coronal mass ejections (CMEs) which can accelerate electron beams and generate radio bursts. This study investigates the physical mechanism responsible for a type II burst that occurs in the absence of a CME.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
B. T. Wang, X. Cheng, H. Q. Song, M. D. Ding
Summary: This study investigates a well-observed coronal mass ejection (CME) and reveals the relationship between the overexpansion phenomenon and other characteristics during its formation, as well as the radio bursts generated from the interaction with nearby streamers.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Rui Liu, Yuming Wang
Summary: This study focuses on the spatiotemporal structures of supra-arcade spikes (SASs) to investigate their characteristics. The results show that the widths of spikes are log-normal distributed and the Fourier power spectra of the overall supra-arcade extreme ultraviolet emission are power-law distributed, indicating the fragmentation of the VCS. By comparing the number of SASs and the turns of field lines as derived from the ICMEs, the study found consistent results for three events but a significant difference for the fourth event with an exceptionally fast CME speed, suggesting different characteristics of the ICME.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Astronomy & Astrophysics
Manon Jarry, Alexis P. Rouillard, Illya Plotnikov, Athanasios Kouloumvakos, Alexander Warmuth
Summary: This study analyzes the geometrical and kinematic properties of coronal and interplanetary shock waves produced by CMEs. The results show the evolution of the shock wave's shape, expansion speeds, and their correlation with the underlying flare activity. These findings contribute to improving space weather forecasting and understanding the eruption process of CMEs.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Aiying Duan, Chaowei Jiang, ZhenJun Zhou, Xueshang Feng
Summary: This paper investigates the initiation mechanism of the first on-disk X-class eruptive flare in solar cycle 25. The study reveals a magnetic flux rope (MFR) consistent with a pre-existing filament before the flare, suggesting that the eruption of the whole filament indicates the eruption of the MFR. Quantitative analysis shows that the pre-flare MFR resides too low to trigger a torus instability, while the pre-flare evolution of the current density suggests the formation of a vertical current sheet before the eruption. The study suggests that the event follows a reconnection-based initiation mechanism, in which the eruption is initiated by reconnection in a gradually formed current sheet.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Aabha Monga, Rahul Sharma, Jiajia Liu, Consuelo Cid, Wahab Uddin, Ramesh Chandra, Robertus Erdelyi
Summary: The study found that the partial eruption of a filament channel was triggered by small-scale flux reconnection/cancellation events, leading to the pile-up of ambient magnetic field and the formation of bright EUV loops in close proximity to the filament channel, resulting in the split of the filament structure vertically.
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY
(2021)
Article
Astronomy & Astrophysics
E. Lumme, J. Pomoell, D. J. Price, E. K. J. Kilpua, M. D. Kazachenko, G. H. Fisher, B. T. Welsch
Summary: This study utilized a data-driven, time-dependent magnetofrictional simulation to examine the pre- and post-eruptive evolution of a solar eruption and highlight the strengths and weaknesses of the simulation approach. The results demonstrate the simulation's effectiveness in modeling the pre-eruptive flux rope system but indicate difficulties in reproducing the post-eruptive ejection.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Astronomy & Astrophysics
Gottfried Mann, Astrid M. Veronig
Summary: This article investigates a dome-shaped extreme-ultraviolet (EUV) wave observed by the EUVI instrument on the STEREO-B spacecraft, which reveals the three-dimensional propagation characteristics of a large-scale EUV wave in the solar corona, considered to be a manifestation of a large-amplitude magnetohydrodynamic (MHD) wave. By measuring the velocity of the EUV wave across the solar surface, the magnetic field of the quiet Sun is determined to be approximately 3.2 G. This study shows that the propagation of the dome-shaped EUV wave can be well described by the theory of large amplitude (simple) MHD waves.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
B. Ehresmann, C. Zeitlin, D. M. Hassler, J. Guo, R. F. Wimmer-Schweingruber, T. Berger, T. D. Matthiae, G. Reitz
Summary: The radiation environment on the surface of Mars is mainly influenced by galactic cosmic rays (GCRs) and solar energetic particles (SEPs). Solar modulation of the GCR flux is the main factor causing changes in the radiation field over years. Dosimetric measurements conducted with the Radiation Assessment Detector (RAD) from 2019 to 2020 show the impact of solar modulation on the Martian surface radiation environment. The results have implications for future human exploration missions of Mars and provide valuable data for validating radiation transport models.
Article
Engineering, Aerospace
Yuming Wang, Xianyong Bai, Changyong Chen, Linjie Chen, Xin Cheng, Lei Deng, Linhua Deng, Yuanyong Deng, Li Feng, Tingyu Gou, Jingnan Guo, Yang Guo, Xinjun Hao, Jiansen He, Junfeng Hou, Jiangjiang Huang, Zhenghua Huang, Haisheng Ji, Chaowei Jiang, Jie Jiang, Chunlan Jin, Xiaolei Li, Yiren Li, Jiajia Liu, Kai Liu, Liu Liu, Rui Liu, Rui Liu, Chengbo Qiu, Chenglong Shen, Fang Shen, Yuandeng Shen, Xiangjun Shi, Jiangtao Su, Yang Su, Yingna Su, Mingzhe Sun, Baolin Tan, Hui Tian, Yamin Wang, Lidong Xia, Jinglan Xie, Ming Xiong, Mengjiao Xu, Xiaoli Yan, Yihua Yan, Shangbin Yang, Shuhong Yang, Shenyi Zhang, Quanhao Zhang, Yonghe Zhang, Jinsong Zhao, Guiping Zhou, Hong Zou
Summary: Solar Ring (SOR) is a proposed space science mission that aims to monitor and study the Sun and inner heliosphere from a full 360 degrees perspective in the ecliptic plane. It will deploy three spacecraft separated by 120 degrees on the 1-AU orbit. With necessary science instruments, it will provide unprecedented capabilities to understand the deep interior of the Sun, the evolution of solar featured structures, and space weather in the inner heliosphere, addressing outstanding questions about solar cycle origin and extreme space weather events.
ADVANCES IN SPACE RESEARCH
(2023)
Article
Astronomy & Astrophysics
J. K. Thalmann, M. Dumbovic, K. Dissauer, T. Podladchikova, G. Chikunova, M. Temmer, E. Dickson, A. M. Veronig
Summary: In this study, we analyze the complete chain of effects caused by a solar eruptive event, aiming to understand the dynamic evolution of magnetic-field-related quantities in interplanetary space. By studying a series of connected events, we identify the magnetic structure and track the evolution of the associated interplanetary coronal mass ejection. Our results suggest a considerable contribution from the eruptive process in the magnetic fluxes and helicities processed by magnetic reconnection.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
Athanasios Papaioannou, Konstantin Herbst, Tobias Ramm, Edward W. Cliver, David Lario, Astrid M. Veronig
Summary: The potential impact of solar superflares on the radiation environment around Earth is assessed by studying the relationship between the peak proton flux and fluence of solar energetic particle (SEP) events and the solar flare soft X-ray peak photon flux.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
L. Rodriguez, A. Warmuth, V Andretta, M. Mierla, A. N. Zhukov, D. Shukhobodskaia, A. Niemela, A. Maharana, M. J. West, E. K. J. Kilpua, C. Mostl, E. D'Huys, A. M. Veronig, F. Auchere, A. F. Battaglia, F. Benvenuto, D. Berghmans, E. C. M. Dickson, M. Dominique, S. Gissot, L. A. Hayes, A. C. Katsiyannis, E. Kraaikamp, F. Landini, Landini, J. Magdalenic, G. Mann, P. Massa, B. Nicula, M. Plana, O. Podladchikova, C. Sasso, F. Schuller, K. Stegen, R. Susino, M. Uslenghi, C. Verbeeck
Summary: We report on a solar-eruptive event that was observed simultaneously by three remote-sensing instruments onboard Solar Orbiter. The eruption was observed by the Extreme Ultraviolet Imager, the corresponding CME was recorded by the coronagraph Metis, and the associated X-ray flare was sampled by the Spectrometer/Telescope for Imaging X-rays. Analysis of the data from these instruments revealed the presence of continuous magnetic reconnection and heating even after the impulsive phase, which has not been reported before for a single event. These observations highlight the scientific potential of Solar Orbiter and other space-based assets.
Article
Astronomy & Astrophysics
Paul Geyer, Mateja Dumbovic, Manuela Temmer, Astrid Veronig, Karin Dissauer, Bojan Vrsnak
Summary: We investigated the interaction between a coronal mass ejection (CME) and a nearby coronal hole (CH) using remote sensing and in situ data. By analyzing ultraviolet images, magnetograms, and coronagraph images, we found that the CME erupts under a streamer, leading to material evacuation and the formation of a CH. The CME's early propagation is likely deflected and it travels southwest of the Sun-Earth line. In situ data revealed the presence of a small flux rope and an Alfvenic wave, suggesting reconnection processes near the ICME and the high-speed stream from the CH.
ASTRONOMY & ASTROPHYSICS
(2023)
Article
Astronomy & Astrophysics
D. Milosic, M. Temmer, S. G. Heinemann, T. Podladchikova, A. Veronig, B. Vrsnak
Summary: The ESWF model is a solar wind forecasting model developed by the European Space Agency's Heliospheric Weather Expert Service Centre. It can predict the solar wind speed at Earth with a lead time of 4 days by using an empirical relation between solar coronal holes area and the observed solar wind speed at 1 AU. The ESWF 3.2 version improves the precision and accuracy of the speed profiles by considering compression and rarefaction effects in interplanetary space, as well as the propagation times and interactions between the Sun and Earth.
Article
Astronomy & Astrophysics
Jian Zhang, Jingnan Guo, Mikhail I. I. Dobynde
Summary: Solar Energetic Particles (SEP) are a significant source of radiation on Mars, and it is crucial to understand their impact on the Martian radiation environment for future human settlements. The absence of a global magnetic field on Mars allows SEPs to directly interact with its atmosphere, leading to varying radiation levels across different locations due to atmospheric thickness differences. By employing advanced simulation methods, we find that even the thinnest Martian atmosphere reduces radiation dose by at least 65% compared to deep space, with the shielding effect increasing in denser atmospheres. Additionally, we present a method to forecast SEP-induced radiation in different regions of Mars with varying surface pressures.
SPACE WEATHER-THE INTERNATIONAL JOURNAL OF RESEARCH AND APPLICATIONS
(2023)
Article
Geochemistry & Geophysics
Salman Khaksarighiri, Jingnan Guo, Robert F. Wimmer-Schweingruber, Sven Loeffler, Bent Ehresmann, Daniel Matthiae, Donald M. Hassler, Cary Zeitlin, Thomas Berger
Summary: Through simulation experiments, it was found that the angle of incidence of high-energy particles interacting with the Martian atmosphere has a significant impact on the surface radiation dose, especially for galactic cosmic ray protons and helium ions, with incident angles of approximately 74° and 46°, respectively. These results are important for future human exploration of Mars, as they can be used to assess the effectiveness of radiation shielding for a given geometry or optimize the radiation shielding design of a Martian habitat.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Editorial Material
Astronomy & Astrophysics
Mateja Dumbovic, Fang Shen
Article
Astronomy & Astrophysics
Christina O. Lee, Beatriz Sanchez-Cano, Gina A. DiBraccio, Majd Mayyasi, Shaosui Xu, Phillip Chamberlin, Emma Davies, Camilla Scolini, Rachael J. Filwett, Robin Ramstad, Erika Palmerio, Benjamin J. Lynch, Janet G. Luhmann, Bent Ehresmann, Jingnan Guo, Robert C. Allen, Sarah Vines, Reka Winslow, Heather Elliott
Summary: This article discusses the knowledge gaps and open questions about solar and interplanetary drivers of space weather conditions at Mars, and emphasizes the urgency for continuous observations. Recommendations include supporting heliophysics and space weather science advancements at about 1.5 AU, prioritizing upstream Mars L1 monitors and/or areostationary orbiters, and establishing collaborations between federal agencies and international partners.
FRONTIERS IN ASTRONOMY AND SPACE SCIENCES
(2023)
Article
Engineering, Multidisciplinary
ZhuXuan Zou, YuMing Wang, TieLong Zhang, GuoQiang Wang, SuDong Xiao, ZongHao Pan, ZhouBin Zhang, Wei Yan, Yang Du, YuTian Chi, Long Cheng, ZhiYong Wu, XinJun Hao, YiRen Li, Kai Liu, ManMing Chen, ZhenPeng Su, ChengLong Shen, MengJiao Xu, JingNan Guo
Summary: The Mars orbiter magnetometer (MOMAG) is a scientific payload onboard the Tianwen-1's orbiter. However, the orbiter is not magnetically cleaned and the boom where the magnetometer's sensors are placed is not long enough. This poses challenges to the magnetic field data processing. In this study, the in-flight calibration process of Tianwen-1/MOMAG is introduced. The calibrated magnetic field data are compared with MAVEN, revealing consistent physical structures and similar magnetic field strength distributions in the solar wind, suggesting the success of MOMAG's in-flight calibration.
SCIENCE CHINA-TECHNOLOGICAL SCIENCES
(2023)
Article
Andrology
Lorena Rodriguez-Paez, Charmina Aguirre-Alvarado, German Chamorro-Cevallos, Alcantara-Farfan Veronica, Calderon-Espinosa Sandra Irel, Castillo-Perez Hugo, Carlos Armando Garcia-Perez, Guadalupe Elizabeth Jimenez-Gutierrez, Joaquin Cordero-Martinez
Summary: This study evaluated the effects of spermine, spermidine, and putrescine on sperm motility, capacitation, and acrosome reaction. The results showed that polyamines significantly decreased these parameters and may act by inhibiting the activity of sAC. Furthermore, polyamines also caused a decrease in cAMP concentration.
SYSTEMS BIOLOGY IN REPRODUCTIVE MEDICINE
(2023)
Article
Astronomy & Astrophysics
R. Jarolim, J. K. Thalmann, A. M. Veronig, T. Podladchikova
Summary: The application of physics-informed neural networks enables real-time estimation of the solar coronal magnetic field. A comparison with extreme-ultraviolet observations reveals a realistic approximation and a clear relationship between the modelled coronal field and flaring activity.