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Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Zhenying Han, Yu Huang, Guanyu Jia, Lei Jing, Shengxuan Huang, Can Li, Weiqun Lei, Wenmin Hu

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Anupam Ghosh, Sachikanta Nanda, Soma Das

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Yuanxun Zhang, Hao Yue, Zhen Cheng, Jing Huang, Kai Zhou

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Lixiang Wang, Dong Ye, Xianren Kong, Yan Xiao

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): O. Laryunin

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Zhongguang Yang, Lei Deng, Cheng Zhu, Zengshan Yin, Tao He, Yu Huang, Yanping Bai, Hu Jiang, Yong Yang, Ye Zhang, Binglong Chen, Xinyu Li, Yonghe Zhang

Publication date: 1 May 2025

Source: Advances in Space Research, Volume 75, Issue 9

Author(s): A. Lokaveer, Vikram Khaire, Thomas Anjana, Maliyekkal Yasir, S. Yogahariharan, Akash Dewangan, Saurabh Kishor Mahajan, Sakshi Aravind Tembhurne, Gunja Subhash Gupta, Devashish Bhalla, Anantha Datta Dhruva, Aloke Kumar, Koushik Viswanathan, Anand Narayanan, Priyadarshnam Hari

Publication date: 1 May 2025

Source: Advances in Space Research, Volume 75, Issue 9

Author(s): Qicheng Xu, Min Hu, Yuqiang Fang, Xitao Zhang

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Mohammad Amin Shahriari, Hossein Aghighi, Mohsen Azadbakht, Davoud Ashourloo, Ali Akbar Matkan, Foad Brakhasi, Jeffrey P. Walker

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Marzieh Mokarram, Tam Minh Pham

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Zeeshan Basar Sheikh, Satadal Ghosh

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Junjun Liu, Yufu Cui, Haoping Wang, Xingyu Zhou, Linghui Yu

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Kyohei Akiyama, Oliver Montenbruck

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Arvind Chandra Pandey, Anikul Islam, Bikash Ranjan Parida, Chandra Shekhar Dwivedi

Publication date: 15 April 2025

Source: Advances in Space Research, Volume 75, Issue 8

Author(s): Nikita V. Belyakov, Svetlana Illarionova

SummaryThis study presents the results of an interlaboratory test designed to evaluate the accuracy of Spectral Induced Polarization (SIP) measurements using controlled electrical test networks. The study, conducted in Germany since 2006, involved 12 research institutes, six different impedance measurement devices, and four types of electrical test networks specifically designed to evaluate phase shift errors in SIP measurements. The test networks, with impedances ranging from 100 kΩ to 150 kΩ, represent high-impedance samples with different phase characteristics, and pose the measurement challenges typical of such samples, including high contact impedances and parasitic capacitances. Four key findings emerged from the study: (1) Impedance measurements across all devices showed deviations within 1% over a wide frequency range (0.001 Hz - 1000 Hz); (2) phase errors remained below 1 mrad up to 100 Hz for most devices, but increased at higher frequencies due to parasitic capacitances and electromagnetic coupling effects; (3) lab-specific instruments have lower phase errors than field instruments when used in a laboratory environment, primarily due to the effects of long cables and too low input impedances of the field instruments; and (4) short cables and driven shielding technology effectively minimized parasitic capacitance and improved measurement accuracy. The study highlights the usefulness of test networks in assessing the accuracy of SIP measurements and raises awareness of the various factors influencing the quality of SIP data.

SummaryGas-bearing sediments in shallow-water environments have recently attracted attention from the perspectives of energy resources, potential geohazards, and climate change. Our laboratory measurements demonstrate the potential for gas-bubble manipulation in gas-bearing sands via radiating repeated pulse signals. By monitoring the temporal changes in the waveform of repeated ultrasonic pulse irradiation with a dominant frequency of 100 kHz transmitted through gas-bearing sand, we observe energy amplification and a frequency shift toward the dominant frequency in the recorded waveforms over 880 h. These results imply that gas bubbles may deform or move autonomously to propagate irradiated ultrasonic waves most efficiently and thereby minimize the energy loss of the transmitted waves. Gas bubbles larger than sand grains detected using three-dimensional X-ray computed tomography cannot explain the phenomena of energy amplification and frequency shifts, indicating the need for a higher spatial resolution to capture the behavior of smaller gas bubbles.

SummaryAirborne magnetotelluric (AirMT) systems generate transfer function data from magnetic fields measured in the air and either electric or magnetic fields measured at a base station. AirMT anomalies are fundamentally controlled by the anomalous magnetic fields within the survey region. While AirMT data acquired using a magnetic field base station are not directly sensitive to the conductivity at the base station, AirMT data acquired using an electric field base station are scaled by the inverse square root of the conductivity at the base station. The transfer function data collected by various AirMT systems have different sensitivity functions. Consequently, the inversion of AirMT data for different acquisition systems may not recover the same conductivity model for the same set of inversion parameters. In this paper, we aim to characterize the fundamental similarities and differences between AirMT inversion for data collected using a magnetic field base station, and for data collected using an electric field base station. We adopt an unconstrained, smoothest model inversion approach to characterize the structures that are naturally recovered by inverting AirMT data when the base station is far away and located on the surface of a homogeneous quarter-space. Our work shows that when a-priori knowledge of the host conductivity within the survey region is available, AirMT inversion effectively recovers conductive and resistive structures within the survey region, regardless of whether the data are collected using an electric or magnetic base station. We show that a single ground magnetotelluric station might provide enough information about the host conductivity to construct a suitable starting model for AirMT inversion, and we discuss the impact of jointly inverting AirMT data and ground magnetotelluric data for a single station.

Publication date: Available online 17 April 2025

Source: Advances in Space Research

Author(s): Zhenyu He, Yang Yang, Wu Chen, Ning Cao, Yajuan Guo

Publication date: Available online 16 April 2025

Source: Advances in Space Research

Author(s): Arfa Mubashir, Ashwin Ashok, Megan Connors, Xiaochun He, H.A. Tharindu G. Hettiarachchi, Petrus Martens, Enosh H. Mudiyanselage, Unil A.G. Perera, Ernesto Potdevin, Viacheslav M. Sadykov, Murad Sarsour, Mihailo Savić, Nikola Veselinović