Article
Multidisciplinary Sciences
Norihiko Sugimoto, Yukiko Fujisawa, Hiroki Kashimura, Katsuyuki Noguchi, Takeshi Kuroda, Masahiro Takagi, Yoshi-Yuki Hayashi
Summary: Gravity waves play essential roles in the terrestrial and Venus atmosphere by propagating globally and transferring momentum and energy. The small-scale gravity waves are generated spontaneously from thermal tides in Venus atmosphere, acting as primary sources in low latitudes and essential sources in mid- and high latitudes. These waves affect the three-dimensional structure of super-rotation and contribute to material mixing through breaking processes.
NATURE COMMUNICATIONS
(2021)
Article
Astronomy & Astrophysics
Q. Xu, X. Xu, T. L. Zhang, Z. J. Rong, M. Wang, J. Wang, Y. Ye, Z. Zhou, Q. Chang, J. Xu, X. Wang, L. Luo
Summary: The Venusian plasma environment is divided into two regions by the IMB, with its location affected by solar activity and solar wind. The distance of the Venusian IMB on the dayside increases with solar activity but decreases with increasing solar wind dynamic pressure and interplanetary magnetic field cone angle. The behaviors of the IMB are similar to those of the ionopause, indicating a correlation between the distance of the IMB and the scale of the ionosphere.
ASTRONOMY & ASTROPHYSICS
(2021)
Article
Geosciences, Multidisciplinary
M. Persson, Y. Futaana, R. Ramstad, A. Schillings, K. Masunaga, H. Nilsson, A. Fedorov, S. Barabash
Summary: Research indicates that an important process of losing water in Venusian atmosphere is due to the energy and momentum transfer from the solar wind to atmospheric particles. Furthermore, under the Venusian induced magnetosphere, only an average of 0.01% of available power is transferred through oxygen ion escape, with the percentage decreasing as available energy increases.
GEOPHYSICAL RESEARCH LETTERS
(2021)
Article
Engineering, Aerospace
Sara Seager, Janusz J. Petkowski, Christopher E. Carr, Sarag J. Saikia, Rachana Agrawal, Weston P. Buchanan, David H. Grinspoon, Monika U. Weber, Pete Klupar, Simon P. Worden, Iaroslav Iakubivskyi, Mihkel Pajusalu, Laila Kaasik
Summary: Scientists have been considering the potential existence of life in the clouds of Venus for over half a century. In situ atmospheric measurements using modern instruments can determine whether the cloud decks have the necessary characteristics to support life. A suite of instruments is proposed to measure the acidity, water content, presence of metals, organic material, and biosignature gases in the droplets. The mission also serves as preparation for sample return by studying the non-liquid cloud particles and informing collection and storage methods.
Article
Geosciences, Multidisciplinary
Natalie Kaifler, Bernd Kaifler, Markus Rapp, David C. Fritts
Summary: The document describes the research on polar mesospheric clouds (PMCs) observed by the Balloon Lidar Experiment (BOLIDE), including the calculation method of the detection parameter and the scientific exploration of the dataset. The study found that the PMC layer exhibits a variety of responses to larger-scale gravity waves and breaking gravity waves, including accompanying instabilities.
EARTH SYSTEM SCIENCE DATA
(2022)
Article
Geosciences, Multidisciplinary
Brian E. Wood, Phillip Hess, Jacob Lustig-Yaeger, Brendan Gallagher, Daniel Korwan, Nathan Rich, Guillermo Stenborg, Arnaud Thernisien, Syed N. Qadri, Freddie Santiago, Javier Peralta, Giada N. Arney, Noam R. Izenberg, Angelos Vourlidas, Mark G. Linton, Russell A. Howard, Nour E. Raouafi
Summary: Images of Venus taken by the Wide-Field Imager for Parker Solar Probe (WISPR) telescope on the Parker Solar Probe spacecraft reveal thermal emission from the planet's surface, providing the shortest wavelength observations of this emission ever recorded. These observations represent the first detection of the Venusian surface by an optical telescope below 0.8 μm. The images also show bright nightglow emission and are consistent with previous spectroscopic measurements.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Astronomy & Astrophysics
C. Signoles, M. Persson, Y. Futaana, S. Aizawa, N. Andre, S. Bergman, A. Fedorov, V. Lindwall, N. Martinez, C. Mazelle, S. Rojas Mata, A. Wolff, T. L. Zhang
Summary: Investigations of the boundaries and their variability of the induced magnetosphere on Venus can help us understand the solar wind's effect on Venus and unmagnetized planets. Using data from Venus Express, this study finds that the location of the bow shock is mainly influenced by the solar cycle and dynamic pressure, while the ion composition boundary shows clear changes during solar maximum but no clear trends during solar minimum.
ASTROPHYSICAL JOURNAL
(2023)
Article
Astronomy & Astrophysics
Maosheng He, Joachim Vogt, Eduard Dubinin, Tielong Zhang, Zhaojin Rong
Summary: The study investigates the Venusian solar-wind-induced magnetosphere using unbiased statistical methods with high spatial resolution. Results show that the structures in the magnetosphere exhibit IMF dependence, with the cylindrical magnetic component being more intense in the hemisphere with an upward solar wind electric field. These structures, such as low-ionosphere magnetization and looping structures, are spatially separate and exhibit unique characteristics under different IMF conditions.
ASTROPHYSICAL JOURNAL
(2021)
Article
Geosciences, Multidisciplinary
Takeshi Horinouchi, Takehiko Satoh, Javier Peralta
Summary: Recent observations of the lower to middle cloud region of Venus by the Akatsuki orbiter have revealed a variety of cloud features indicative of vortices and waves, contradicting the previous assumption of a dynamically quiet region. The discovery of gigantic cyclonically rotating vortices on August 25, 2016, supports the theory of barotropic instability and is significantly larger in size and spacing compared to previous observations of Venus and Earth's troposphere.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Chemistry, Physical
Zhong Zheng, Jianqiu Wang, Pengqing Bi, Junzhen Ren, Yafei Wang, Yi Yang, Xiaoyu Liu, Shaoqing Zhang, Jianhui Hou
Summary: A advanced interconnecting layer for tandem organic solar cell is developed in this study. By controlling the O-2 flux during evaporation, efficient electron extraction and low Schottky barrier are obtained, enabling effective charge recombination between two subcells. The tandem cell with the interconnecting layer shows a high efficiency of 20.27%.
Article
Environmental Sciences
Pedro Machado, Thomas Widemann, Javier Peralta, Gabriella Gilli, Daniela Espadinha, Jose E. Silva, Francisco Brasil, Jose Ribeiro, Ruben Goncalves
Summary: New results of zonal and meridional winds in both hemispheres of Venus were obtained through ground- and space-based coordinated observations. Doppler velocimetry and cloud-tracked techniques were used to retrieve wind velocities, showing an altitude difference of approximately four kilometers between the two methods. Comparison with atmospheric models and previous observations suggested coherence and complementarity in results, with differences possibly related to atmospheric fluctuations and observational conditions.
Article
Astronomy & Astrophysics
A. P. Dimmock, Yu. V. Khotyaintsev, A. Lalti, E. Yordanova, N. J. T. Edberg, K. Steinvall, D. B. Graham, L. Z. Hadid, R. C. Allen, A. Vaivads, M. Maksimovic, S. D. Bale, T. Chust, V. Krasnoselskikh, M. Kretzschmar, E. Lorfevre, D. Plettemeier, J. Soucek, M. Steller, S. Stverak, P. Travnicek, A. Vecchio, T. S. Horbury, H. O'Brien, V. Evans, V. Angelini
Summary: This study investigates the complex features of the Venus bow shock crossing measured by Solar Orbiter during the first flyby. Multiple large amplitude magnetic field and density structures were observed, as well as higher frequency waves. The study highlights the need to distinguish between large amplitude waves and spatial structures such as shock rippling, and demonstrates the complex nature of energy dissipation at the shock and the importance of understanding cross-scale coupling in these regions.
ASTRONOMY & ASTROPHYSICS
(2022)
Article
Geosciences, Multidisciplinary
Tianning Su, Zhanqing Li, Youtong Zheng
Summary: Due to surface heating, the morning boundary layer undergoes a transition from stable to neutral or convective conditions, which has a significant impact on low tropospheric thermodynamics. The interactions between low clouds and the boundary layer development are complex and uncertain. Our study reveals that cloud-surface coupling can influence the morning transition process, with decoupled clouds causing delays and even preventing the transition in some cases, while coupled clouds facilitate sub-cloud convection and lead to an unstable boundary layer in the earlier morning.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Geochemistry & Geophysics
Hiroki Ando, Masahiro Takagi, Hideo Sagawa, Norihiko Sugimoto, Miho Sekiguchi, Yoshihisa Matsuda
Summary: The study reproduced a quasi-periodic variation of lower cloud amount induced by atmospheric waves in the Venus general circulation model for the first time, which agrees well with previous infrared nightside measurements. This result may explain the mechanism of periodic brightness variation in the low latitudes of Venus shown by previous infrared nightside measurements.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2021)
Article
Geochemistry & Geophysics
Tomoya Suda, Takeshi Imamura, Yeon Joo Lee, Atsushi Yamazaki, Takehiko Satoh, Takao M. Sato
Summary: The temporal variation of the mesoscale ultraviolet (UV) contrast of Venusian clouds was studied using images taken by the UV camera on Akatsuki. The mesoscale contrast was found to oscillate with periods of 4-5 Earth days, which are also the periods of planetary-scale waves. The mesoscale contrast tends to be enhanced when the background becomes darker, suggesting that solar heating feeds the mesoscale dynamics.
JOURNAL OF GEOPHYSICAL RESEARCH-PLANETS
(2023)
Article
Astronomy & Astrophysics
K. S. Obenberger, D. C. Bowman, E. Dao
Summary: This experiment presents a method for detecting chemical explosions equivalent to one ton of TNT using pulsed Doppler radar observations of isodensity layers in the ionospheric E region. The method was successful in the first campaign but failed to detect any signals in the second campaign.
Article
Astronomy & Astrophysics
E. J. Bird, J. M. Lees, J. Kero, D. C. Bowman
Summary: When an acoustic wave encounters a topographic feature, it scatters and loses some of its energy. In this study, we observed the scattered acoustic waves that travel upward before refracting back to the ground. These waves were intercepted by balloon-borne infrasound microbarometers in the lower stratosphere over northern Sweden. The presence of the scattered waves generated a coda, which can be linked to the topography beneath the balloons and low-altitude acoustic ducts. The inclination of the coda signals changed over time, indicating waves arriving from scatterers closer to the receivers. These observations provide insights into the mechanism of amplitude loss due to scattering, which was previously difficult to measure. They contribute to a better understanding of the interaction between atmospheric infrasound propagation and the solid earth.
EARTH AND SPACE SCIENCE
(2022)
Article
Robotics
Loy McGuire, Tristan Schuler, Michael Otte, Donald Sofge
Summary: We present a novel distributed robotic swarm algorithm inspired by the open channel siphon phenomenon in certain viscoelastic fluids. The algorithm mitigates the trapping effects of local minima in potential fields by propagating gradient information through local communication in the robot swarm. Experimental results show that the algorithm reduces the susceptibility of the robot swarm to local minima.
IEEE ROBOTICS AND AUTOMATION LETTERS
(2022)
Article
Geochemistry & Geophysics
Keehoon Kim, Daniel C. Bowman, David Fee
Summary: Underground explosions produce infrasound in the atmosphere, with wavefield characteristics determined by ground surface motions. Finite-difference methods are commonly used for infrasound simulation, but simple point-source approximation may not capture the complexity of explosion-induced ground motions. This study develops a distributed point-source representation of the ground motions for accurate infrasound prediction.
SEISMOLOGICAL RESEARCH LETTERS
(2022)
Article
Geosciences, Multidisciplinary
Siddharth Krishnamoorthy, Daniel C. Bowman
Summary: Barometers floating on high-altitude balloons have been used to detect and characterize acoustic waves generated by seismic activity in the cloud layer of Venus. Garcia et al. (2022) recently demonstrated the successful detection of low-frequency sound caused by earthquakes from stratospheric balloons, providing preliminary findings on earthquake magnitude and location inversion. This study highlights the feasibility of balloon-based investigations of Venus' interior and discusses the limitations and open research questions in this area.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Environmental Sciences
Elizabeth A. Silber, Daniel C. Bowman, Miro Ronac Giannone
Summary: High-altitude infrasound sensing has become more common in recent years, especially in regions where traditional ground-based sensing is not feasible. Airborne sensors, similar to ground-based detectors, can detect low frequency acoustic waves generated by impulsive atmospheric events such as explosions. In this study, infrasound sensors attached to solar hot air balloons in the stratosphere detected signals from the Apollo detonation at distances of 170-210 km. The signals showed three distinct arrival phases, indicating multipathing caused by small-scale atmospheric perturbations. The study also revealed a more complex acoustic environment at these altitudes than previously believed.
Article
Geochemistry & Geophysics
Trevor C. Wilson, Fransiska K. Danneman Dugick, Daniel C. Bowman, Christopher E. Petrin, Brian R. Elbing
Summary: Earthquakes generate inaudible acoustic signals known as infrasound, which can be detected hundreds to thousands of kilometers away. These signals provide valuable information about the earthquake's properties and the local environment.
BULLETIN OF THE SEISMOLOGICAL SOCIETY OF AMERICA
(2023)
Article
Astronomy & Astrophysics
K. S. Obenberger, F. K. Dannemann Dugick, D. C. Bowman
Summary: The detection of relatively low yield chemical explosions in the ionospheric E region using pulsed Doppler radar observations has been confirmed for the first time. This technique can enhance the remote detection of both anthropogenic and natural explosive events.
EARTH AND SPACE SCIENCE
(2023)
Article
Geosciences, Multidisciplinary
S. K. Popenhagen, D. C. Bowman, C. Zeiler, M. A. Garces
Summary: This study used a helium-filled balloon and a smartphone to collect acoustic signals from stratospheric explosions, and compared the collected signals with those from other sensors to reveal the possibilities and limitations of collecting acoustic data from the stratosphere.
GEOPHYSICAL RESEARCH LETTERS
(2023)
Article
Astronomy & Astrophysics
S. A. Albert, D. C. Bowman, E. A. Silber, F. K. Dannemann Dugick
Summary: Researchers have recorded the first infrasound detection of a ground truth airborne source within the theorized atmospheric layer called the AtmoSOFAR channel, using an infrasound sensor on a solar hot air balloon. This study confirms the existence of the AtmoSOFAR channel and demonstrates the ability to record acoustic signals within it. The lack of detections on ground-based stations highlights the advantages of using balloon-borne infrasound sensors to detect objects in the atmosphere.
EARTH AND SPACE SCIENCE
(2023)
Article
Engineering, Aerospace
Adrien Bouskela, Alexandre Kling, Tristan Schuler, Sergey Shkarayev, Himangshu Kalita, Jekan Thangavelautham
Summary: The preliminary design of sailplanes for Mars exploration is presented in this study. These sailplanes mitigate weight and energy storage limitations in powered flight by utilizing atmospheric wind gradients for dynamic soaring and slope/thermal updrafts for static soaring. The results show that the total sailplane energy increases by 6.8-11% at the end of a complete dynamic soaring cycle. Without a propulsion system, the sailplanes can be packaged into CubeSats and deployed as secondary payloads, providing scientific data from inaccessible locations.
Article
Acoustics
Daniel C. Bowman, Jerry W. Rouse, Siddharth Krishnamoorthy, Elizabeth A. Silber
Summary: Free-floating balloons can be used for infrasound recording and geolocation of acoustic sources using aeroseismometry.
JASA EXPRESS LETTERS
(2022)
Article
Engineering, Aerospace
A. I. Krikunova, A. D. Cheshko, V. V. Krivets
Summary: Fire safety is crucial for the development of efficient and safe energy systems for space objects. This paper focuses on studying the influence of gravity on combustion processes and analyzes the dynamics of inverted conical methane-air flame under external acoustic excitation. The results show that at high excitation frequencies, the intensity of vortex generation is similar to that observed in experiments with normal gravity, indicating the dominance of acoustic mechanism. Additionally, at an external excitation frequency of 240 Hz, significant growth in shear vortex diameters and increased amplitude of perpendicular oscillations of flame branches were observed, indicating the most intensive large scale instability of flow.
Article
Engineering, Aerospace
Liya Huang, Mingquan Gong, Jiarui Zhang, Kun Liang, He Yang
Summary: Metallized gel propellants with exceptional stability and remarkable shear-thinning properties were successfully synthesized by utilizing cooperative hydrogen bonding between polymer octanoyl cellulose and the small Thixatrol ST molecule.
Article
Engineering, Aerospace
Clemence Poirier, Michelle Hermes, Marco Aliberti
Summary: This paper examines the role of space-based data in European climate policies and assesses the barriers to the use of space technology in climate policymaking in European countries. The research findings indicate that while satellite data is crucial for scientific research and climate policies, the role of space is not accurately reflected in European climate policies.
Article
Engineering, Aerospace
Yan-mei Zhou, Ji-ping Wu, Wei Huang, Gautam Choubey
Summary: This study investigates the combustion performance of sinusoidal pulsed jets in supersonic flows using numerical simulations. It is found that the pulsed jets can significantly improve combustion efficiency.
Article
Engineering, Aerospace
Wang Zhao, Shujun Tan, Yiliang Guo
Summary: This study proposes an adaptive Pogo active suppression controller design method that utilizes measured acceleration as feedback. The eigenspace transformation theory is employed to design dimensional reduced models for observer and adaptive controller, effectively addressing the issues of model parameter uncertainty and time-varying parameters. Simulation analysis of a certain type of rocket demonstrates the effectiveness of the proposed method.
Article
Engineering, Aerospace
A. V. Nebylov, V. A. Nebylov
Summary: This article discusses the safety issues of astronauts during the landing process and investigates how rescuers can effectively carry out rescue missions. The article also takes into account the special maritime conditions of the Vostochny cosmodrome.
Article
Engineering, Aerospace
Pietro Davide Maddio, Rosario Sinatra, Alberto Meschini, Riccardo Rigato, Marco Lapi, Davide Scarozza, Alessandro Cammarata
Summary: This study aims to develop a versatile cable net generation algorithm for designing offset cable nets in parabolic reflectors. The study proposes a methodology that leverages quasi-geodesic curves and introduces two types of these curves. The study also presents various solutions for different cable net layouts and introduces a quality index based on an equilateral triangle cable net.
Article
Engineering, Aerospace
Nahum Melamed, Tom Heinsheimer
Summary: Traditional methods of asteroid trajectory modification rely on impact or nuclear detonation, while centrifugal propulsion offers an alternative approach. The centrifuge system lands on the asteroid and gradually adjusts the trajectory using momentum transfer. This method allows for flexibility in operation parameters and has the potential to be used in planetary defense and other space missions.
Article
Engineering, Aerospace
Andrew Barth, Ou Ma
Summary: As humans continue to explore the surfaces of the Moon and Mars, the use of distributed heterogeneous robot teams can increase the chances of success by utilizing the complementary capabilities and synergy of the team members. Effective cooperation and collaboration between the members of a robot team is crucial, but defining a metric for effective cooperation is challenging. This paper presents a method for determining reward criteria that can be used for training robot swarm through reinforcement learning techniques. The trained robot team exhibits high success rates and cooperative behavior in test environments, demonstrating the robustness and scalability of the training strategies.
Article
Engineering, Aerospace
Kaijie Zhu, Qiquan Quan, Dewei Tang, Yachao Dong, Kaiyi Wang, Bo Tang, Qi Wu, Zongquan Deng
Summary: This study proposes a deployable Mars quadcopter for air patrol and sampling missions. By describing its structure, avionics architecture, and autonomous flight control method, it provides a feasible framework for future Mars flight sampling missions.
Article
Engineering, Aerospace
Avishai Melamed, Adi Rao, Sarah Kreps, Erika Palmer
Article
Engineering, Aerospace
Colin Hunter, Avinkrishnan Vijayachandran, Anthony M. Waas
Summary: Deployable structures inspired by origami have gained significant prominence in space applications. Recent advancements in multi-material additive manufacturing have opened new possibilities for the fabrication of monolithic structures. This paper presents a novel framework for designing deployable structures using viscoelastic hinges incorporated into rigid plates. Experimental results demonstrate the effectiveness and feasibility of these hinge designs in real-world applications.
Article
Engineering, Aerospace
Aleksander V. Efremov, Mikhail S. Tiaglik, Aleksey S. Tiaglik, Iliyas Kh Irgaleev, Tatyana V. Voronka
Summary: Theoretical and experimental studies were conducted to determine the best kind of information presented on a predictive display for the highest accuracy in space mission execution, while considering reduced propellant consumption.
Article
Engineering, Aerospace
Fuwen Liang, Long Miao, Feng Tian, Jiahui Song, Ningfei Wang, Xiao Hou
Summary: This study investigates the influence of deployment friction on the dynamic characteristics of nonconductive space tether through experimental measurement and numerical simulation. The results show that deployment friction significantly limits the uncontrolled tether deployment, while increasing the initial deployment velocity and satellite effective mass, as well as decreasing orbital altitude, can enhance the deployment capability and dynamic stability. In addition, an optimal matching relationship between tether length and satellite total mass is proposed, which is of substantial importance for the design of nonconductive space tether systems.
Article
Engineering, Aerospace
Amirah R. Algethami, Colin R. McInnes, Matteo Ceriotti
Summary: This paper utilizes the Hill's approximation model to manipulate the relative motion of two asteroids by three impulses, resulting in their bound binary motion in Earth's orbit. The feasibility of this strategy is demonstrated, and potential applications for parking small captured near-Earth asteroids in Earth's orbit are discussed.
