Spacecraft - Science topic

Dear Colleagues, A nonlinear system with symmetry can be decomposed into interconnected lower-dimensional subsystems, where the subsystem architecture is determined by the symmetry group's structure. For general nonlinear control systems, the concept of symmetry can be used to analyze stability, design controllers, and construct observers. Further...

Resident Space Objects (RSO) are human-made objects in orbit around Earth and can remain there for an extended period. These objects can include active satellites, rockets, and space stations, as well as debris caused by previous space endeavours. Debris originated as a consequential outcome of activities such as space launches, orbital missions an...

The interaction of x-ray pulses with metallic and semiconductor materials has a wide range of applications in defense, nuclear fusion, and material processing. As such, thermal analysis of x-ray interactions with materials is crucial, particularly for ultrashort and short pulses (ranging from femtoseconds to a few nanoseconds). Similar to optical l...

Propagation of satellite orbits about celestial bodies frequently relies on spherical harmonics to model the gravitational field. Yet, the expansion of the gravitational field in terms of spherical harmonics only converges exterior to the Brillouin (circumscribing) sphere of the body, limiting the accuracy of the model for very low orbits or landin...

Length of day (LOD), a critical component of Earth orientation parameters (EOP), represents variations in Earth's rotation rate. It is very difficult to predict accurately due to the effects of atmosphere, ocean, hydrology, the Earth's internal interactions and so on. The international Earth rotation and reference systems service (IERS) EOP C04 ser...

As China’s first asteroid exploration mission, the TianWen-2 spacecraft mainly focuses on surface sampling on the near-Earth asteroid 2016 HO3. Different from the usual sampling strategy of releasing a small lander or ejecting a projectile, the whole TianWen-2 spacecraft will be controlled to achieve touchdown and sampling. However, sampling on a l...

Autonomous navigation for spacecraft missions in cislunar space would greatly reduce the workload of ground stations, which is going to significantly increase in the next years. This study evaluates the performance of a spacecraft-to-spacecraft optical-only navigation strategy and perform a robust trajectory optimization according to a recently int...

Sensing atomic and molecular emissions from the radiant plasma sheath that forms around reentry spacecraft will advance the understanding and modeling of high-enthalpy flows. Optical emission spectroscopy (OES) measurements in this extreme environment can yield data needed to anchor aerothermal flow models in the Mach [Formula: see text] regime. Th...

This work proposed research of the emission of electrons born from the outside of spacecraft under the influence of solar radiation. The results can be used to combat harmful noises, which can lead to the failure of devices. On the other hand, these results can be used to create new devices for studying solar activity.

Bilobed bodies represent a significant class of small extraterrestrial objects in the Solar System. We present a double harmonic-series approach to model the gravity of the lobes separately, thereby allowing their mass distributions to be constrained independently. We study an exemplary candidate contact binary, comet 67P/Churyumov-Gerasimenko, and...

The current LAGEOS–LARES 2 experiment aims to accurately measure the general relativistic Lense–Thirring effect in the gravitomagnetic field of the spinning Earth generated by the latter’s angular momentum $${\varvec{J}}$$ J . The key quantity to a priori analytically assess the overall systematic uncertainty is the ratio $${\mathcal {R}}^{J_2}$$ R...

Due to the scarcity of in situ measurements in the thermosphere, the retrieval of thermospheric mass density primarily relies on model simulations or the inversion of satellite accelerometers and orbital data. Density derived from satellite inversion is more accurate, often reflecting the actual density at the satellite altitude. However, due to th...

Kinetic‐scale magnetic holes (KSMHs) are ubiquitous quasi‐steady magnetic structures and vital energy conversion channels in various space plasmas, for example, terrestrial foreshock and magnetopause reconnection region. However, the energy conversion mechanism within KSMHs remains unclear. We identified a KSMH within the magnetotail reconnection d...

**Gravitational Tensor-Magnetics (GTM): A Paradigm Shift with Transformative Applications** This work explores the groundbreaking **Gravitational Tensor-Magnetics (GTM) theory**, which unifies magnetic fields, quantum entanglement, and spacetime curvature, offering a fresh perspective on fundamental forces. GTM reinterprets cosmic phenomena like d...

On 10 May 2024, a super space storm—characterized by the Dst index plummeting to −412 nT and induced by a strong coronal mass ejection on the Sun—attacked the Earth's magnetosphere. This geomagnetic storm, according to the human record of Dst index, is the third‐strongest one throughout history (only slightly lower than those in 1989 and 2003). In...

The space environment is subject to various cosmic rays and high-energy particles, which inevitably causes damage to space-borne equipment, posing a threat to the safety and reliability of spacecraft operation. As a critical part of interconnection in electronic components, it is of great significance to study the reliability of solder joints under...

The Earth's magnetospheric cusp region is an important pathway for solar wind particles entering the magnetosphere and ionospheric ions escaping. The plasma density is a key parameter for understanding this physical process. Based on measurements from the Cluster‐3 spacecraft (2001–2010), we selected 878 cusp crossing events (470 in the northern an...

Spacecraft catering to the Lunar Gateway or other “permanent” stations in the lunar vicinity would require frequent travel between periodic orbits around the Earth–Moon L1 and L2 Lagrange points. The transition through the Hill sphere is often characterized by close passages of our nearest neighbor—rendering the optimization problem numerically cha...

This paper presents an attitude stabilization algorithm for a Low Earth Orbit (LEO) Earth-pointing spacecraft using magnetorquers as the only torque actuators and employing Model-Free Adaptive Control (MFAC) as the control algorithm. MFAC is a data-driven control algorithm that relies solely on input-output data from the plant. This paper validates...

Inertial sensors are commonly used in many applications for a while. They provide important information about the orientation but are prone to structural errors, which makes it impossible to use their raw data. Particularly for gyroscopes, deterministic errors such as bias, misalignment, or scale factor errors can affect their performance dramatica...

Plain Language Summary We explore Saturn's small‐scale atmospheric dynamics by analyzing data from the final phase of the Cassini mission. As the spacecraft flew between Saturn's rings and upper atmosphere, it collected detailed gravity measurements that provided important insights into the planet's winds and their depths. While Saturn's large‐scal...

The precision of clinical treatment planning systems for particle therapy is limited (among other reasons) by the absence of measurements on the differential fragmentation cross sections generated during interactions between light ions (such as C and O) and hydrogen-enriched targets. To address this issue, the FOOT experiment has been designed to t...

Magnetopause reconnection is the dominant mechanism for transporting solar wind energy and momentum into the magnetosphere‐ionosphere system. Magnetopause reconnection can occur along X‐lines of variable extent in the direction perpendicular to the reconnection plane. Identifying the spatial extent of X‐lines using satellite observations has critic...

How impulsive solar energetic particle (SEP) events are produced by magnetic-reconnection-driven processes during solar flares remains an outstanding question. Here we report a short-duration SEP event associated with an X-class eruptive flare on July 03, 2021, using a combination of remote sensing observations and in situ measurements. The in situ...

An ultra-high-frequency (UHF) deployable conical log spiral antenna’s design and experimental test results are presented. The antenna is a spring constructed from a carbon-fiber-infused epoxy matrix. The spring design simplified the spacecraft deployment mechanism, and the use of composite materials allowed for the integration of radiating elements...

This work aims to synthesize a controller that ensures that an unknown discrete-time system is incrementally input-to-state stable ($\delta$-ISS). In this work, we introduce the notion of $\delta$-ISS control Lyapunov function ($\delta$-ISS-CLF), which, in conjunction with the controller, ensures that the closed-loop system is incrementally ISS. To...

This paper conducts a comprehensive study on the nonlinear dynamic modeling of the two test masses Drag-Free and Attitude Control System (DFACS) for heliocentric gravitational wave detection missions. First, the composition of DFACS and the modeling assumptions are clarified, key reference frames and their transformation relationships are defined,...

Recently, Seligman et. al. (2024) identified a population of near-Earth objects (NEOs) that exhibit statistically significant non-gravitational accelerations with no coma, and labeled them dark comets. Here, we show that one of these objects, 2005 VL1, was at closest approach to Earth in November 1965 when the Venera 2 spacecraft was launched to ex...

Liquid directional transport surfaces have the ability to control the movement of liquids in specific directions, making them highly applicable in various fields such as heat transfer, fluid management, microfluidics, and chemical engineering. This review aims to summarize the research progress on liquid directional transport surfaces and spacecraf...

Plain Language Summary The O(¹S) 557.7 nm dayglow emission has been recently discovered in the Martian dayside atmosphere, having a primary and secondary emission peak observed at ∼80 and ∼120 km altitudes, respectively. It is produced via photodissociation of CO2 by solar extreme ultraviolet radiation and electron impact processes. It is to be not...

The Athena mission entered a redefinition phase in July 2022, driven by the imperative to reduce the mission cost at completion for the European Space Agency below an acceptable target, while maintaining the flagship nature of its science return. This notably called for a complete redesign of the X-ray Integral Field Unit (X-IFU) cryogenic architec...

A proposed Vera C. Rubin Observatory Deep Drilling micro-survey of the Kuiper Belt will investigate key properties of the distant solar system. Utilizing 30 hours of Rubin time across six 5-hour visits over one year starting in summer 2026, the survey aims to discover and determine orbits for up to 730 Kuiper Belt Objects (KBOs) to an $r$-magnitude...

Plain Language Summary Atmospheric gravity waves (AGW) are wave‐like disturbances that travel through a planet's atmosphere, much like waves moving across water's surface. These waves influence weather patterns and the overall behavior of the atmosphere. Studying them on Mars helps us understand not only the Martian atmosphere but also provides ins...

Two similar-looking, two-part interplanetary type II burst events from 2003 and 2012 are reported and analysed. The 2012 event was observed from three different viewing angles, enabling comparisons between the spacecraft data. In these two events, a diffuse wide-band type II radio burst was followed by a type II burst, which showed emission at the...

Servicer spacecraft supply fuel to a client via on-orbit refueling technology, which can extend the lifespan of the client. However, during refueling, the inertia of the combined spacecraft varies continuously due to the liquid fuel flow, which risks disrupting the attitude motion. To guarantee the attitude stabilization of the combined spacecraft...

Plain Language Summary Spacecraft measurements in the Earth's magnetosheath showed that electric field fluctuations at electron scales are predominantly electrostatic and consist, in particular, of bipolar solitary waves, whose properties, nature, and origin have not been addressed statistically. This letter presents a statistical analysis of solit...

We demonstrate the global response of the ionosphere to the geomagnetic super storm on 10–11 May 2024. The in situ observations from the Swarm spacecraft show a rapid depletion of plasma density in the dawn and dusk sectors following the storm. The in situ data are further complemented by the ground‐based total electron content maps. Both the in si...

Plain Language Summary Scientists have recently been paying more attention to “whistler‐mode waves” in Jupiter's magnetosphere, as these waves play a key role in the movement of high‐energy electrons within Jupiter's radiation belts. A recent study by Ma, Li, Zhang, Kang, et al. (2024), https://doi.org/10.1029/2024gl111882, using data from NASA's J...

A significant amount of space debris has been left behind throughout the history of space exploration. This debris poses a threat to spacecraft operating in orbit and to human activities on Earth. Spacecraft may become inoperable due to collisions with debris, and the increasing amount of debris limits available space for future missions. Consequen...

In the context of space exploration, spacecraft are frequently subjected to hypervelocity impact from space debris, which can result in significant damage. To avoid or mitigate the impact damage caused by space debris, the deployment of Whipple shields in front of bulkheads has been identified as a highly effective protective strategy. This paper p...

During a Juno spacecraft encounter with Jupiter's volcanic moon Io (30 December 2023), the Jupiter Energetic Particle Detector Instrument (JEDI) observed Energetic Neutral Atoms (ENAs) of >150 keV oxygen and sulfur (O + S) coming from Io's mostly nightside atmosphere. JEDI lines‐of‐sight approached closest to Io between 1.31 and 1.49 Io radii (RIo)...

The Jupiter Icy Moons Explorer (JUICE) is a European Space Agency mission to explore Jupiter and its three icy Galilean moons: Europa, Ganymede, and Callisto. Numerous JUICE investigations concern the magnetised space environments containing low-density populations of charged particles that surround each of these bodies. In the case of both Jupiter...

As autonomous systems are being developed in multiple industries it has been recognized that a phased approach is needed both for technical development and user acceptance. Partially in response, the automotive and aircraft industries have published five or six Levels of Autonomy in an attempt to broadly characterize the amount of autonomy technolo...

The purposes of this study are to establish facility which contains a low Earth orbit (LEO) complex environmental simulation chamber and a geostationary orbit (GEO) spacecraft charging chamber, to demonstrate its feasibility and to analyze how much passive elements, glass fiber-reinforced polymer (GFRP), and printed circuit board (PCB) are affected...

The chapter titled “Aerospace and Thin Films” discusses the importance of thin film coatings in the field of aerospace, mainly with regard to aircraft as well as spacecraft. In this chapter, the literature describes the types of advanced coatings that are used in the aerospace industry for the improvement of performance and for increasing the lifes...

As autonomous systems are being developed in multiple industries it has been recognized that a phased approach is needed both for technical development and user acceptance. Partially in response, the automotive and aircraft industries have published five or six Levels of Autonomy in an attempt to broadly characterize the amount of autonomy technolo...

This paper investigates the attitude tracking control of a liquid-filled spacecraft, addressing the challenges such as large-amplitude liquid sloshing, external disturbances, and actuator faults. To overcome these issues, a novel proportional-integral-derivative (PID) dynamic sliding mode fault-tolerant control with time-delay estimation (TDE-PID-D...

This paper provides a theoretical overview of a Z-pinch magnetic nozzle plasma propulsion system designed for Low Earth Orbit (LEO). The system utilizes trapped charged particles from the spacecraft's environment and magnetic confinement to generate thrust, reducing the need for onboard propellants. By employing a magnetic mirror configuration, the...

This research investigates the rotational dynamics of a charged axisymmetric spinning rigid body influenced by gyrostatic torque. The study also accounts for the effects of transverse and constant body-fixed torques and an electromagnetic force field. Euler's equations of motion are employed to formulate the governing equations for the system. Give...

Dynamically modeling the flexible characteristics of large-scale jointed composite spacecraft is challenging. In this study, a dynamic modeling method for rigid–flexible composite spacecraft is proposed based on the absolute nodal coordinate formulation (ANCF). First, the spacecraft in the jointed composite is simplified as a rigid body, and the do...

This brief tackles the predefined-time attitude tracking problem with guaranteed performance for rigid spacecraft subject to uncertain inertia, external disturbances, and actuator partial failure. Firstly, a nonlinear prescribed performance function (NPPF) is constructed, and a non-singular predefined-time terminal sliding mode (NPTSM) surface inte...

Cloud cover is a key meteorological element that plays a crucial role in Earth's climate system and remains a significant source of uncertainty in climate estimations. Over recent decades, changes in the frequency of certain cloud types have been observed in Poland, including increases in high and convective clouds and a decrease in stratiform clou...

The ESA-TRP SPADEXO project investigated the use of thermites to provide additional enthalpy to a spacecraft re-entering towards the Earth, with the objective of limiting its casualty risk on ground. Steel mock-ups inspired by the geometry of solar array drive mechanisms were filled with thermite and placed in DLR’s L2K arc-heated hypersonic wind t...

Since its orbit insertion on 4 July 2016, the Juno spacecraft has orbited Jupiter in a highly elliptical, polar orbit. With every orbit, Juno's line of apsides migrates, increasing the angle relative to the Jovian equator. Therefore, the spacecraft traverses across the inner regions of the radiation belt, where energetic particles are trapped. The...

This paper offers new insights into gravitational interactions within a general non-inertial reference frame. By utilizing symbolic tensor calculus, the study establishes a unified framework that connects time derivatives in non-inertial frames to those in inertial frames. The research introduces new first integrals of motion for a system of many p...

Understanding the properties, especially the magnetohydrodynamic (MHD) invariants, of coronal mass ejections (CMEs) measured in-situ is key to bridging the CME properties from the Sun to interplanetary space. In order to investigate CMEs from the in-situ measurements that provide a one-dimensional (1-D) cut of the CME parameters over the spacecraft...

Stream interaction regions (SIRs) are long-lasting solar wind structures that result from stable fast solar wind interacting with preceding slow solar wind. These structures have been examined in depth throughout the heliosphere, particularly at 1 au; however, due to sparse observations, SIRs have not been characterized thoroughly at 1.5 au. Thanks...

This report investigates the application of design thinking principles to optimize the trajectory and operations of a lunar lander. By considering the spacecraft as the "user" within the design thinking framework, we aim to identify and address critical challenges during key mission phases: Earth Escape, Orbital Insertion, Lunar Transfer Trajectory...

Advanced navigation capabilities are essential for precise landing operations, enabling access to critical lunar sites and supporting future lunar infrastructure. To achieve accurate positioning, innovative navigation methods leveraging neural network frameworks are being developed to detect distinctive lunar surface features, such as craters, from...

Plain Language Summary Around Earth, the movement of high‐energy particles coming from outside of our solar system is significantly influenced by structures of plasma flowing from the Sun in regions where faster, hotter flows catch up to slower, denser streams. We perform a statistical analysis of spacecraft data to find the average profile of vari...

Obtained images from the Cassini spacecraft have unveiled several small satellites in the vicinity of Mimas’ orbit: Aegaeon, Methone and Anthe. Methone and Anthe are situated within arcs of material, while Aegaeon orbits within an arc near the inner edge of Saturn’s G ring. The presence of these arcs and moons is consistent with their confinement b...

Gridded ion engines, such as the radio-frequency ion thruster, are highly efficient designs for generating thrust on satellites or spacecrafts for both commercial and scientific missions, due to the very high exhaust velocities achieved. A thorough understanding of the low-temperature and low-pressure plasma parameters is essential in order to char...

Studies for inferring the global characteristics of coronal mass ejections (CMEs) from its multipoint local in situ observations have been undertaken earlier, but there are limited studies utilizing measurements from multiple spacecraft with sufficiently small radial and angular separations. In the present study, we investigate a magnetic cloud (MC...

In addition to sunspots, the most easily visualized manifestation of solar magnetism, cutting-edge observations of the solar atmosphere have uncovered a plethora of magnetic flux tubes, down to the resolving power of modern high-resolution telescopes (a few tens of kilometers), revealing how the Sun is a fully magnetized star. These magnetic elemen...

In addition to sunspots, which represent the most easily visualized manifestation of solar magnetism, cutting-edge observations of the solar atmosphere have uncovered a plethora of magnetic flux tubes, down to the resolving power of modern high-resolution telescopes (a few tens of km), revealing how the Sun is a fully magnetized star. These magneti...

Polarimetric radio occultations (PROs) of the Global Navigation Satellite System are able to characterize precipitation structure and intensity. Prior studies have shown the relationship between precipitation and water vapor pressure columns, known as the “precipitation pickup.” Less is known about the relationship between the vertical distribution...

It is well known that mean elements obtained by canonical perturbation theory only agree partially with the average dynamics of the osculating orbit. While this fact does not necessarily compromise the accuracy of corresponding perturbation solutions, the loose use of the terminology “mean elements” in artificial satellite theory may obscure the un...

Auroral streamers are important meso-scale processes of dynamic magnetosphere-ionosphere coupling, typically studied using imagers sensitive to energetic (>1 keV) electron precipitation, such as all-sky imagers (ASIs). This paper reports streamer-like red-line auroras, representing low-energy (<1 keV) precipitation, observed poleward of a black aur...

Data from the FAST spacecraft are used to study the temporal progression of the energy inputs to the dayside cusp and the nightside aurora, including Poynting flux, electron number flux and amplitude of extremely low frequency (ELF) waves, during a CME-driven storm, and the resulting H⁺ and O⁺ outflows. The results show that (1) On the dayside, Poy...

Radiation emitted from Hall thrusters in the GHz range has been observed to occur as short pulses. The origin of this emission is still unclear and raises questions of both physical understanding and electromagnetic compatibility between the thruster and the spacecraft. In this work, experimental investigations of a connection between the pulses ap...

This research addresses minimum-fuel pinpoint lunar landing at the South Pole, focusing on trajectory design and near-optimal guidance aimed at driving a spacecraft from a circular low lunar orbit (LLO) to an instantaneous hovering state above the lunar surface. Orbit dynamics is propagated in a high-fidelity ephemeris-based framework, which employ...

The evolution of the properties of short-scale electrostatic waves across collisionless shocks remains an open question. We use a method based on the interferometry of the electric field measured aboard the magnetospheric multiscale spacecraft to analyze the evolution of the properties of electrostatic waves across four quasi-perpendicular shocks,...

The observation of electrostatic double layers in Martian magnetosheath plasma is reported, based on medium-frequency (100 Hz-32 kHz) electric field data recorded by the Langmuir Probe and Waves on board the Mars Atmosphere and Volatile Evolution spacecraft on 2021 January 1. A total of six burst mode events were scrutinized, revealing the occurren...

A heat exchanger enables heat transfer between two fluids without mixing them. Its performance depends on factors like temperature difference, heat transfer area, and fluid flow rates. Heat exchangers are used in industries such as petroleum refining, food processing, nuclear power, thermal management in spacecraft, and electricity production. This...

Lightsails are a highly promising spacecraft concept that has attracted interest in recent years due to its potential to travel at near-relativistic speeds. Such speeds, which current conventional crafts cannot reach, offer tantalizing opportunities to probe nearby stellar systems within a human lifetime. Recent advancements in photonics and metama...

Safe and reliable lunar landings are crucial for future exploration of the Moon. The regolith ejected by a lander’s rocket exhaust plume represents a significant obstacle in achieving this goal. It prevents spacecraft from reliably utilizing their navigation sensors to monitor their trajectory and spot emerging surface hazards as they near the surf...

The Laser Interferometer Space Antenna (LISA) will be the first space-based gravitational wave (GW) observatory. It will measure gravitational wave signals in the frequency regime from 0.1 mHz to 1 Hz. The success of these measurements will depend on the suppression of the various instrument noises. One important noise source in LISA will be tilt-t...

For nonlinear systems that admit continuous-time stabilizing controllers, we propose a Lyapunov-based technique to map this continuous-time control input into a sequence of discrete impulses while guaranteeing the desired performance of the closed-loop system. Specifically, a numerical algorithm, running in real-time, determines the instants of con...

Asteroids have formed during the evolution of the disk in the early Solar System and, in general, do not have spherical and symmetrical shapes. The reason for those irregular shapes is the small mass of the bodies, such that gravity is insufficient to generate a spherical shape. Those irregular shapes make the study of spacecraft orbits investigati...

This paper presents a comparative analysis of dual and joint estimation methods for simultaneous state and parameter estimation schemes utilized for the motion of a rigid body spacecraft in the presence of disturbances caused by onboard sloshing propellant. The joint method integrates parameters as additional states within the state vector, while t...

The geometry of the terrestrial magnetized environment, or geospace, varies widely in space and time due to the Earth’s magnetic field interactions with the interplanetary medium. A spacecraft’s location in geospace is only approximately determined by its coordinates since the environment is inhomogeneous, with distinct physical processes occurring...

The visible and infrared Moon And Jupiter Imaging Spectrometer (MAJIS), aboard the JUpiter ICy Moons Explorer (JUICE) spacecraft, will characterize the composition of the surfaces and atmospheres of the Jupiter system. Prior to the launch, a campaign was carried out to obtain the measurements needed to calibrate the instrument. The aim was not only...

Amidst the current challenges facing Earth, such as resource scarcity, unsustainable population growth, and climate change, this paper explores the potential for interplanetary travel, specifically assessing the feasibility of reducing travel time from Earth to another habitable planet, Kepler-22b. By adopting the Python programming language to val...

To provide autonomous and accurate time service for deep space missions, a pulsar observation–based timekeeping method is documented in this paper, which utilizes pulsars as the time information source. Firstly, the pulsar observation noise is remodeled as the combination of the Gaussian noise and colored noise, and the detailed expression of the c...

Spacecraft approaching maneuver control normally uses traditional control methods such as Proportional–Integral–Derivative (PID) or Model Predictive Control (MPC), which require meticulous system design and lack robustness against unknown disturbances. To address these limitations, we propose an end-to-end asymmetric Deep Reinforcement Learning-bas...

NASA's Double Asteroid Redirection Test (DART) spacecraft impacted Dimorphos, the natural satellite of (65803) Didymos, on 2022 September 26, as a first successful test of kinetic impactor technology for deflecting a potentially hazardous object in space. The experiment resulted in a small change to the dynamical state of the Didymos system consist...

Spacecraft trajectory optimisation represents a pillar for space mission development, as it allows the design of more cost-effective and high-performance operational concepts. In this context, the Mars exploration race, best epitomised by the Mars Sample Return mission (MSR), has highlighted the need to optimise not only the Keplerian phase traject...