Transmissive solar sail designs have been proposed with performance and utility benefits over traditional solar sails, particularly in low Earth orbit. The functional element of these new sails is their refractive or diffractive surface pattern. This paper explores the design of refractive sail patterns using numerical optimisation, and explores the validity of using model-free reinforcement learning

The transition between combustion processes or modes of scramjet engines is high-speed and dynamic, which may lead to unstable or even runaway. It is crucial to identify the combustion state of scramjet engine for controlling and maintaining stable operation. Based on the methods of contrastive learning, a clustering network model of combustion processes is developed to deal with the schlieren image

To investigate the effect of the initial surface oxide layer on boron regarding high-temperature thermal oxidation and ignition combustion performance, boron powder was subjected to aging under varying temperature and humidity conditions. The thickness of the surface oxide layer was analyzed and quantified using transmission electron microscopy (TEM) and digital microscopy software. The thermal oxidation

Star sensors experience significant degradation in attitude measurement accuracy under dynamic conditions, primarily caused by motion-induced star image blurring and diminished effective stars. This review analyzes the underlying mechanisms responsible for accuracy deterioration in dynamically perturbed star sensors. As the first comprehensive survey in this field, the paper proposes a novel taxonomy

Reusable liquid propellant rocket engines are critical propulsion systems for future space launches and, with the increasing diversity of space missions, have become a prominent research focus in the aerospace field. To address the unclear response characteristics of a reusable high-pressure staged combustion LOX/kerosene variable-thrust rocket engine, a simulation platform was established for a specific

In the framework of Space Situational Awareness activities, space debris light curve analyses have been used as a tool to study the tumbling motion of uncontrolled orbiting objects using only optical data and often without any assumptions about their geometry. Through this strategy, frequency analysis can be performed to extract the objects' rotation periods, which are necessary to predict variations

Thrust regulation has been a major challenge to the solid rocket motor. The dynamic combustion and response characteristics of a novel combined solid rocket motor regulated by a pintle valve are numerically studied in this paper. A two-dimensional transient combustion model of the combined motor is established. The results show that as the flow regulation ratio increases, the species mixing in the

A cornerstone of the United States space policy is fostering a robust commercial space industry to leverage the benefits of competitive market forces. Space sector stakeholders generally applaud the implementation of this policy decision in the launch industry, citing significant decreases in space launch costs in the last decade. The effectiveness of this policy can be examined through two lenses:

A numerical study on the effect of H2/O2 concentration gradient on detonation re-initiation behind the pre-detonator tube was carried out using an OpenFOAM based solver DCRFoam. Simulations of the processes rely on solving the Navier-Stokes equations. The results indicate that the cellular size increases with the increase of hydrogen volume fraction. And the decoupled degree of detonation is higher

The hindlimb unloaded (HU) mouse is an established model of simulated microgravity with pathologies of various body organs. However, the relevant effects of concomitant hypoxia in HU mice are unknown. We have developed a novel mouse model of hypoxia and HU to better simulate spaceflight conditions. Here, we investigated the cytoarchitecture and gene expressions of skeletal muscle, lungs, and liver

The aerodynamic drag of the spacecraft in Very Low Earth Orbit (VLEO) has an important effect, and the implementation of Atmosphere-Breathing Electric Propulsion (ABEP) is anticipated to facilitate long-duration, cost-effective missions in VLEO. The balance between the acquisition and utilization of resources and aerodynamic drag should be considered in the geometric design of spacecrafts based on

The exploration of the Moon necessitates sustainable habitat construction. Establishing a permanent base on the Moon requires solutions for challenges such as transportation costs and logistics, driving the emphasis on In-Situ Resource Utilization (ISRU) techniques including Additive Manufacturing. Given the limited availability of regolith on Earth, researchers utilize simulants in laboratory studies

This study presents the performance characterization of a design alternative to low-power water-fueled Hall thrusters focusing mainly on the thermal design and magnetic topology intending to allow long-term continuous operation without active cooling mechanisms. The thruster was characterized using direct thrust measurement and far-field plasma diagnostics including an on-axis retarding potential analyzer

Gateway will represent a vital asset for future lunar and deep space exploration. This research considers a chaser vehicle that aims at approaching and mating with Gateway, through the use of low-thrust propulsion for orbit control and reaction wheels for attitude maneuvering. Orbit dynamics of Gateway is simulated in a high-fidelity ephemeris-based dynamical framework, while the approaching path of

H2O extraction from remote icy lunar regolith using concentrated irradiation was investigated under high-vacuum and low-temperature conditions. The thermal sublimation of H2O(s) from packed beds of lunar regolith simulants was quantified with and without an indirect solar receiver for average concentrated irradiations of 37.06 ± 2.66 and 74.62 ± 3.57 kW/m2. The indirect solar receiver increased sublimation

Very Long Baseline Interferometry (VLBI) provides the finest angular resolution of all astronomical observation techniques. However, observations with Earth-based instruments are approaching fundamental limits on angular resolution. These can only be overcome by placing at least one interferometric element in space. In this paper, several concepts of spaceborne VLBI systems are discussed, including

The attitude dynamics of a spacecraft employing a large rotating appendage is complex, and control and determination of its attitude and pointing can be a real challenge considering the impact system uncertainties and sensor errors can have on the mission scientific products. The aim of this paper is to develop a multi-rigid-body model that describes the rotational motion of an Earth-observing scientific

The multi-wheeled pressurized lunar rover (MWPLR) is an essential vehicle for future long-term operations on the moon. When the MWPLR travels on a rugged lunar surface, if equipped with a bogie suspension (BS) or double-wishbone suspension (DWS), it will have difficulty withstanding heavy loads, absorbing shocks, or ensuring the passive adaptation of multiple wheels to the lunar surface. To solve the

With the rapid advancement of aerospace technology, the development of hypersonic vehicles has garnered increased attention. The challenges related to thermal protection during hypersonic flight have emerged as a critical limiting factor and significant technological bottleneck for further progress. This paper examines the thermal protection structures for large area of hypersonic vehicles, offering

Spaceflight is an isolated and confined environment (ICE) that exposes astronauts to psychological hazards, such as stress, danger, and monotony. Virtual reality (VR) and artificial intelligence (AI) technologies can serve as psychological countermeasures as they can digitally simulate immersive environments, interactive companions, and therapeutic experiences. Our study employs a scoping literature

The rapid growth in satellite deployments, particularly with the emergence of large constellations, has amplified concerns over the sustainability of the orbital environment. Space mission operators can utilize different mechanisms during the design and operation of their missions to adhere to space sustainability best practices. This paper presents the Space Sustainability Rating (SSR), a novel initiative

Hansen’s ideal frame integration method is leveraged with the techniques of manifold projection. Taking the zonal problem of the Earth as a model, it is shown that a simple, computationally inexpensive, energy-scaling calibration using the manifold projection approach clearly improves the geometric description of the orbit by radically reducing the dominant along-track errors typical of perturbed Kepler

Space propulsion using pulsed-laser ablation of metals is a promising technology, particularly for deorbiting space debris or satellites at the end of life. The momentum coupling coefficient, a key parameter in this technology, depends on the incident laser wavelength. Although former studies have evaluated this dependency, they often overlooked the influence of variations in beam profiles. A method

Over the last decade there have been numerous studies that propose regolith-based materials, such as regolith based geopolymers and sintered blocks, for permanent manned missions on the lunar surface, like those proposed by space agencies like the National Aeronautics and Space Administration in the US. In this review paper the current state of research was investigated for both of the materials described

The solidification and molding of lunar regolith are essential for constructing lunar habitats. This study introduces an innovative lunar regolith molding technique that synergistically combines solar concentration, flexible optical fiber bundle energy transfer, and powder bed fusion. A functional prototype is developed to validate the proposed scheme. Systematic experiments including fixed beam spot

This study investigates the formation and evolution of craters under near-vacuum conditions due to supersonic jet impingement, with a focus on regolith particle ejection dynamics. Experiments were conducted at the Plume-Regolith Facility of the University of Glasgow, where controlled jet pulses (0.1, 0.5 and 1.0 s) were directed to high- and low-density regolith simulants. Using Particle Image Velocimetry

This study presents autonomous guidance and control strategies for reconfiguring close-range multi-satellite formations. The formation consists of N under-actuated deputy satellites and an uncontrolled virtual or physical chief spacecraft. Each deputy is equipped with a single throttleable but ungimbaled low-thrust nozzle, requiring a combination of thrust and coast arcs, during the latter attitude

Boron-based nanofluid fuel demonstrates a high energy density due to the presence of B nanoparticles (BNPs). This paper presents a comprehensive study of nanofluid fuels composed of kerosene, 1-pentanol, and BNPs through both theoretical analysis and experimental investigation. The 1-pentanol not only possesses a high heat value and physical properties, such as density and viscosity, that are comparable

The problem of triaxial stabilization of the satellite position in the orbital reference frame is considered. The satellite moves in a medium-height circular orbit, has a controlled electrostatic charge and its own magnetic moment. The question is raised on the possibility of implementing such a system of electrodynamic control of the angular position of the satellite in which the influence of the

Venus has long been of interest in humankind’s understanding of how Earth, and Earth-like rocky bodies, form and evolve in our solar system. A key missing capability for our exploration of Venus are technologies which can navigate through the atmosphere recurrently and over extended periods of time, with minimal power. Recently, the Jet Propulsion Laboratory (JPL) has developed a variable altitude

High volume exercise is crucial in preventing spaceflight-induced muscle atrophy but can induce reductions in body mass and fat mass, due to a mismatch between energy intake and total energy expenditure (TEE). This randomized cross-over trial investigated whether short-duration resistive-vibration exercise (RVE) prevents muscle loss without inducing negative energy balance during a medium-duration

This article presents the impedance control method for a serial-parallel hybrid space robot system (HSRS) including a robotic arm and a parallel platform in Stewart configuration, and achieves compliance and stability during assembly operations. In this article, the dynamic model of the HSRS is established firstly with considering the influence of external forces, which is the foundation of subsequent

To realize a fully water-vapour propellant Hall-effect thruster, hundreds of watt-class Hall effect thrusters have been tested with different propellants, including xenon and water-vapour, cathode, hollow cathode, and microwave discharge cathode. The current characteristics and ion beam currents were measured and compared for different combinations. From the test results, it was observed that the difference

Dual Bumper Whipple shields have been employed for spacecraft protection for many decades, with extensive experimental and numerical studies dedicated to characterizing their impact resistance. Over the years, advancements have introduced novel design modifications, including fluid-filled containments, foam-filled cores, and shear-thickening fluids in the inter-bumper spaces, enhancing their protective

Directed panspermia involves the deliberate spread of life between planets by intelligent actors. While it was originally proposed to explain the origin of life on Earth, recent advancements in space and bio-technology suggest that humans could soon attempt this – and perhaps even succeed. Biocentric ethical theories support attempting directed panspermia to increase life’s cosmic abundance and to

Inertial Measurement Units (IMUs) are critical for spacecraft attitude control, navigation, and positioning. Anomaly detection is essential to ensure the safe and stable operation of these systems. However, existing anomaly detection methods face challenges in terms of precision, generalization, and the interpretability of captured features. To address these issues, this paper proposes an anomaly detection

Light detection and ranging (lidar) is valuable during non-cooperative space rendezvous scenarios. By processing the 3D point clouds, it is possible to provide a navigation solution, consisting of an estimate of the relative pose of the approached spacecraft. To enable a safe rendezvous, the pose estimation has to be precise, but also robust if the output is used as a primary navigation solution. Navigation

Metal and metalloid production from lunar regolith simulants via carbothermal reduction was investigated using activated carbon under inert conditions. JSC-1A, LMS-1, and LHS-1 lunar regolith simulants were thermodynamically and experimentally studied over a range of conditions to assess metal and metalloid production as function of oxide and mineral composition. Thermodynamic analysis was conducted

Interest in the exploitation of the cislunar environment is growing exponentially. The establishment of lunar outposts and orbiting gateways is pivotal to enable the next generation of human exploration in the solar system. This paper investigates the refinement process of prototype Earth–Moon transfers, originally designed in the Earth–Moon, Sun-perturbed bi-circular restricted four-body problem,

The accumulation of space debris in orbit poses significant challenges, consuming limited orbital resources and threatening the safe operation of active spacecraft. For GEO orbits, where natural debris removal mechanisms are virtually absent, active debris capture and removal technologies have become imperative. Existing methods face significant obstacles in achieving effective tether-tugging of space

This systematic review evaluates the efficacy of hyperbaric oxygen therapy (HBOT) on treating ionising radiation injuries and discusses its applicability to space exploration. As human missions venture beyond Earth's magnetic field, astronauts are increasingly exposed to harmful levels of ionising radiation, posing significant health risks. Hyperbaric oxygen therapy, which has been traditionally used

The electrical energy injection and ignition mechanisms of HAN-ECSP (hydroxylamine nitrate-based electrically controlled solid propellant) are critical technology limiting its engineering application. The mechanisms are investigated through the characterization and testing of various samples in this paper. The mixed cross-linking of HAN and PVA (polyvinyl alcohol) is a prerequisite for the injection

This study aimed to deploy two nanosatellites from Technische Universität Berlin, within the scope of the NanoFF mission, directly into a helix orbit using currently available technology to minimize collision risk post-deployment. The methodology involved using D-Orbit’s ION orbital transfer vehicle, launched aboard SpaceX’s Falcon 9 launcher, for the precise deployment of the NanoFF satellites. The

With more spacecraft launched in Low Earth Orbit (LEO) for educational and research purposes, their mission completion or mission failure results in an increasing number of inactive orbiting space bodies. These uncooperative bodies can lead to collision with other space systems, creating the need to actively remove debris for collision avoidance and to increase the availability of orbital slots. Solutions

Missions to small bodies require accurate shape characterization for navigation and scientific purposes. In this paper, a Shape from Silhouette (SfS) algorithm is presented which uses the visual extents of the body (silhouettes) in a set of infrared images to infer its three-dimensional shape. The algorithm leverages intersections between rays (each corresponding to a silhouette pixel) from different

Precise on-orbit assembly of Space Solar Power Station imposes great challenges on its effective rigid–flexible coupling dynamics modeling and low vibration control. This paper presents an integrated framework combining a reduced-order dynamics model and an improved fractional-order controller of Space Solar Power Station. The dynamics model, developed through Lagrangian equations and finite element

This paper presents a validation framework using data for uncertainty propagation techniques for space situational awareness (SSA) applications. In particular, we validate a novel technique for uncertainty propagation, dubbed here as Orthogonal Probability Approximation (OPA) This technique describes the evolution of state/parameter uncertainties, e.g. initial condition and/or drag coefficient, of

This paper describes the trades carried out and lessons learned while performing the preliminary design of the Capture, Containment, and Return System as part of the Mars Sample Return campaign, before the re-architecture studies initiated after December 2023. Mars Sample Return is an effort to bring to Earth rock cores, regolith, and atmospheric samples from Mars inside sealed tubes. The importance

Ionic liquid electrospray propulsion systems are a promising technology for the rapidly growing small satellite market, potentially exhibiting high specific impulse and efficiency even at very low power. Direct performance characterization of electrospray thrusters is a challenging issue, given the low thrust and mass flow rate values. In this work, an analytical balance was modified for direct performance

Atomization is one of the critical challenges in the application of nanoparticle–laden gel propellants due to their high viscosity and complex rheological properties. This study investigates the rheological properties and atomization characteristics of gel containing varying concentrations of nanoparticles in impinging jet injectors. The rheological behavior of the gels was measured to characterize

In recent years, lunar constellation design and deployment has attracted a strong interest from the scientific community and the major space agencies. Indeed, a similar space infrastructure will represent a valuable asset for navigation and telecommunications purposes, useful to many robotic and human activities on the lunar surface. This study focuses on the analysis, design, and testing of three

This paper investigates the configuration stability and rigid–flexible coupled dynamics of maneuverable space tether nets under impact loads. To analyze the complex 3D maneuvers of the net, a geometric mechanics framework is developed, incorporating the rigid–flexible coupling between wave propagation in the net and the attitude dynamics of maneuvering satellites attached to its corners. A coordinate-free

In this paper, a spacecraft formation flying in the gravitational and magnetic fields of the Earth is investigated. The “direct magnetic dipole” is considered as a model of the geomagnetic field. A system of nonlinear differential equations describing the relative orbital motion of an electrically charged spacecraft is derived, as well as its simplified version. The analytical research of a spacecraft

The inertial sensor serves as the core payload for space-based gravitational wave detection, providing a stable inertial reference for observing mid-frequency and low-frequency gravitational waves in the universe and black holes. This paper designs a novel three-stage release mechanism for precisely releasing the test mass, namely the physical carrier of the inertial sensor. Due to the nonlinear hysteresis

The on-ground simulation of a free-floating operational environment is an essential part of the spacecraft dynamic validation. In the state-of-the-art, operational limits such as workspace limitation or limited time duration are a typical problem. As a consequence, we propose a redundant cable-driven parallel robot to reproduce a six-dimensional free-floating scenario. An efficient tension distribution

The deployment of large-scale constellations has led to a sharp increase in the number of spacecraft in orbit. To avoid collision risks and overcome the limitations of traditional single spacecraft tracking methods, this paper introduces a multi-spacecraft visual tracking method called SatSORT tailored to the specific requirements of the aerospace field. Based on the DeepSORT framework, the proposed

In 2022, China finished building its own space station—Tiangong-marking a new age of space competition and cooperation. With the pace of retirement for the International Space Station, led by the United States and Russia, China's Space Station (CSS) could become a novel forum for future international cooperation. Against this backdrop, the importance of designing a legal framework, addressing key issues

The effects of flame collision with pressure waves during hydrogen/air flame propagation in a two-dimensional channel with non-slip adiabatic walls are studied for channels with different aspect ratios and a semi-open channel. The problem is solved by direct numerical simulations of the fully compressible Navier-Stokes equations coupled to a detailed chemical model for a stoichiometric hydrogen-air

The Italian Spring Accelerometer (ISA) is a three axis mass–spring accelerometer, one of the payloads of the BepiColombo joint space mission between the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA). At launch in October 2018, BepiColombo started its seven-year cruise as a stack of three different modules, overall named Mercury Composite Spacecraft (MCS). The spacecraft

Gel propellants, which combine the benefits of solid and liquid propellants, suffer from poor atomization quality due to their high viscosity. Sonic atomization technology has demonstrated potential in atomizing high-viscosity non-Newtonian fluids. This study designed a Hartmann whistle injector comprising a central gas path, an annular slit liquid path, and a resonant cavity. Schlieren imaging and