Deep Space Missions Research Articles

Broadening the selection criteria for Astronauts undertaking long-term space travel.

Until recently, the dose limits for astronauts of the National Aeronautics and Space Administration (NASA) varied with age and gender, as the current dose limits do for the Japanese astronauts. In 2022, NASA issued a single career dose limit of 600 mSv in effective dose to all astronauts, based on a median estimate to reach 3% cancer fatality for 35-year-old females. This new limit has been criticized by some experts for the reason that it could weaken the protection of crew health and safety. Considering this situation, we present the conceptual basis of a broader-scope criteria where the radiological health is recognized to be one of the equally important factors and the highest competence is to be achieved as a whole team for the success of a future deep-space mission to the moon and Mars.

Frontier scientific questions in deep space exploration

<p indent="0mm">Deep space exploration is one of the frontiers of scientific research and driven by human instincts to explore the unknown. Since the Moon Race in the 1960s and 1970s, deep-space probes have explored many celestial bodies in our solar system, including eight planets. These explorations have yielded tremendous scientific discoveries, but they also revealed many more unsolved mysteries. The 21st century has witnessed a remarkable increase in deep-space exploration activities, with several new agencies launching their spacecraft in the past few decades. As a result of technological advancement, exploration success rates have improved significantly. A systematic review of frontier scientific questions can provide invaluable references for mission planning strategies and boost scientific discoveries and breakthroughs in the future. In general, these questions are related to three primary scientific subjects: (1) One of the primary scientific objectives of deep-space exploration is to study the origin and evolution of the solar system. From the collapse of the solar nebula to the formation of the planetary system, the solar system has undergone a complex evolutionary process. The components of the current solar system, particularly the residual presolar material, can provide critical information for understanding the initial conditions and evolution of the solar system. The Moon, being the nearest celestial body to Earth, serves as an outpost for exploring other planetary bodies and is especially important for testing deep-space exploration equipment and studying solar system evolution. (2) Another objective of deep space exploration is to better understand the evolution of planetary habitability. The Sun is an important factor affecting habitability, and eruptions of solar activities can have a substantial impact on the space environment of the solar system. The environment of the Earth and other planets has changed dramatically over billions of years of evolution. Although life has only been confirmed on Earth, other celestial bodies might also have had habitable conditions along the evolutionary process. Decoding the evolution of the habitable environment of solar system planetary bodies is of great significance for understanding the formation and evolution of habitable Earth and the origin of life on Earth. (3) Extraterrestrial life detection is a critical scientific topic in deep space exploration, with far-reaching implications for understanding the origin, evolution, and distribution of life in solar and extrasolar systems. The current scientific challenges in the detection of extraterrestrial life primarily involve four aspects: the origin and evolution of life, extraterrestrial habitable environments, life signal identification, and analogy of terrestrial extreme environments. In endeavors to answer these scientific questions, more well-planned deep-space exploration missions are required to collect evidence. In order to outpace opponents in the continuing space exploration endeavor, the National Aeronautics and Space Administration (NASA), the European Space Agency (ESA), and other rising roles have made their ambitious roadmaps. NASA will encourage commercial companies to join future missions through the Artemis program, and has planned missions to explore Venus, asteroids, and icy bodies. The ESA proposed tens of missions in its white paper <italic>Voyage 2050</italic>. In the coming decades, China will lay the groundwork for the International Lunar Research Station through three Chang’e and four Russian Luna missions. Furthermore, Tianwen-2 and Tianwen-3 will return samples from asteroids and Mars, respectively; Tianwen-4 is intended to explore the Jupiter system. The success of these missions will yield unprecedented information for deciphering the mysteries of the solar system and life, as well as considerably expanding our knowledge of the universe we live in.

Phasing with near rectilinear Halo orbits: Design and comparison

In the next future, space agencies are planning to return to the Moon. The objective is to assemble an orbiting space station, called Gateway, on a Near Rectilinear Halo Orbit around the Moon as a base for future Moon and deep space missions. Within this framework, multiple side missions will be planned to sustain the Gateway (Artemis mission). The proposed work is thought in framework of the preliminary design of future cargo missions, in particular on the design of an efficient phasing trajectory, under the Circular Restricted Three body problem hypotheses, to bring a cargo vehicle from the end of the Earth-Moon transfer to the beginning of the proximity operations such as rendezvous and docking with the space station. The work aims covering the lack of literature in phasing trajectories with the NRHO by proposing three different strategies to connect the Earth-Moon transfer trajectory with the proximity operations. The three strategies are classified based on the choice of the parking orbits or the choice of the manifolds. Two strategies use butterfly and Halo orbits to park the vehicle before transferring to the target orbit. The third strategy, instead, uses manifolds to allow a direct phasing. In the paper, the three innovative strategies are designed and compare in a specific scenario.

Astropharmacy: Roles of Pharmacist in Space.

Since disease is a natural aspect of life, human deep space missions will largely depend on preventing disease, diagnosis, and treatment. Pharmaceuticals are used to identify, treat, prevent, or cure illnesses, but they are unstable on Earth and even more so in space. What if the pharmacist could prepare small quantities of medicines in space, on site, as needed? The alteration in pharmacokinetic and pharmacodynamic (PK-PD) and pharmacogenomics with flying and medications will need to be customised for each person individually and specifically at the point of need because of drug stability issues. We can't meet the expense of bringging everything we might need, so pharmacists must devise ways to manufacture medications in-situ and on-demand. With this skill, pharmacists would be able to fulfill the demand of any exploration mission that involved spaceflight with robust pharmaceuticals that would be stable enough to last the duration of the mission, comprehensive enough to treat all potential medical events, safe, and effective, notwithstanding the known PK-PD and pharmacogenetic alterations that take place during spaceflight. The purpose of this article was to review topics related with Astropharmacy. The topics include: the need of Astropharmacy in space, health-related problems caused by hostile space conditions, storage problems in space, methods to establish the stability and effectiveness of pharmaceutical products in space, and alteration in human physiology including PK-PD and pharmacogenomics and highlight the pharmacist's potential roles in the pharmacies orbiting the space.

Motion modeling and blurred image simulation of the star tracker used for deep-space missions

The star tracker is the most accurate attitude measurement device among different types of attitude measurement devices. It is based on captured star images to extract star centroids and then determine attitude. However, images taken by the star tracker under dynamic conditions are often blurred, which limits its dynamic performance. In this paper, we first classify and model motions of the star tracker under dynamic conditions, including rotations and angular vibrations. Then, a motion kernel consisting of three individual descriptors (trajectory, intensity, and point spread function) is proposed to model the motion blurring process and simulate blurred images. Experimental results show that our approach can model a wide variety of blurs including uniform and non-uniform blurs, and it can provide extremely realistic blurred images. These findings are crucial to the subsequent centroid extraction of stars and the dynamic performance of the star tracker.

Exploring the Limits of Synthetic Creation of Solar EUV Images via Image-to-image Translation

The Solar Dynamics Observatory (SDO), a NASA multispectral decade-long mission that has been daily producing terabytes of observational data from the Sun, has been recently used as a use case to demonstrate the potential of machine-learning methodologies and to pave the way for future deep space mission planning. In particular, the idea of using image-to-image translation to virtually produce extreme ultraviolet channels has been proposed in several recent studies, as a way to both enhance missions with fewer available channels and to alleviate the challenges due to the low downlink rate in deep space. This paper investigates the potential and the limitations of such a deep learning approach by focusing on the permutation of four channels and an encoder–decoder based architecture, with particular attention to how morphological traits and brightness of the solar surface affect the neural network predictions. In this work we want to answer the question: can synthetic images of the solar corona produced via image-to-image translation be used for scientific studies of the Sun? The analysis highlights that the neural network produces high-quality images over 3 orders of magnitude in count rate (pixel intensity) and can generally reproduce the covariance across channels within a 1% error. However, the model performance drastically diminishes in correspondence to extremely high energetic events like flares, and we argue that the reason is related to the rareness of such events posing a challenge to model training.

Solar sail-based V-infinity leveraging missions from elliptic orbit

The utilization of V∞ leveraging maneuvers in deep space missions is able to mitigate the mission requirements on launch energy, as the spacecraft propulsive acceleration is used to increase the hyperbolic excess velocity at the starting planet. Usually, such a maneuver is studied in the context of multiple impulsive velocity changes, whereas a few works deal with the use of continuous-thrust propulsion systems. This Short Communication analyzes two-dimensional V∞ leveraging maneuvers of a solar sail-based spacecraft, starting from an elliptic heliocentric orbit. As such, this work completes the model discussed in the recent literature where a circular parking orbit was assumed. The proposed approach allows the designer to obtain an accurate, parametric, analysis of the mission performance in an optimal framework using a classical two-body gravitational model. Assuming a state-of-the-art technology for solar sails, the numerical simulations analyze the performance of those fascinating propellantless propulsion systems in both an Earth- and a Mars-based mission scenario.

Predominant contribution of the dose received from constituent heavy-ions in the induction of gastrointestinal tumorigenesis after simulated space radiation exposure.

Gastrointestinal (GI) cancer risk among astronauts after encountering galactic cosmic radiation (GCR) is predicted to exceed safe permissible limits in long duration deep-space missions. Current predictions are based on relative biological effectiveness (RBE) values derived from in-vivo studies using single-ion beams, while GCR is essentially a mixed radiation field composed of protons (H), helium (He), and heavy ions. Therefore, a sequentially delivered proton (H) → Helium (He) → Oxygen (O) → Silicon (Si) beam was designed to simulate simplified-mixed-field GCR (Smf-GCR), and Apc1638N/+ mice were total-body irradiated to sham or γ (157Cs) or Smf-GCR followed by assessment of GI-tumorigenesis at 150days post-exposure. Further, GI-tumor data from equivalent doses of heavy-ions (i.e., 0.05Gy of O and Si) in 0.5Gy of Smf-GCR were compared to understand the contributions of heavy-ions in GI-tumorigenesis. The Smf-GCR-induced tumor and carcinoma count were significantly greater than γ-rays, and male preponderance for GI-tumorigenesis was consistent with our earlier findings. Comparison of tumor data from Smf-GCR and equivalent doses of heavy ions revealed an association between higher GI-tumorigenesis where dose received from heavy-ions contributed to > 95% of the total GI-tumorigenic effect observed after Smf-GCR. This study provides the first experimental evidence that cancer risk after GCR exposure could largely depend on doses received from constituent heavy-ions.

Autonomous Wheel Off-Loading Strategies for Deep-Space CubeSats

Deep-space CubeSats missions require careful trade-offs on design drivers such as mass, volume, and cost, while ensuring autonomous operations. This work elaborates the possibility of off-loading the reaction wheels without the need of carrying a bulky and expensive reaction control system or the field-dependent magnetotorquers. The momentum accumulated along two body axes can be removed by either offsetting the main thruster with a gimbal mechanism or by tilting differentially the solar wings. The dumping on the third axis can be still accomplished by imposing a specific attitude trajectory with the motion of either the gimbal or the arrays drive mechanism. The M-Argo CubeSat is selected as case study to test the techniques along its deep-space trajectory. The strategies decision-making is autonomously carried out by a state machine. The off-loading during the cruising arcs employs the gimballed thruster and takes typically 3 h, granting a mass savings of more than 99% with respect to the usage of a reaction control system. The trajectory is shown to have negligible differences with respect to the nominal one, since the thrust is corrected accordingly. During the coasting arcs, the solar arrays are tilted and several hours are required, depending on the Sun direction and intensity, but the propellant is completely saved. Sensitivity analyses are also carried out on the initial angular momentum components and the center of mass displacement to check the robustness of the algorithms.

Characterization of Thermal Gradient Effects on a Quartz Crystal Microbalance.

Quartz crystal microbalances are widely used sensors with applications for the detection of very-low-mass deposition in many different fields, from contamination monitoring in the high vacuum of deep space missions to the monitoring of biological activity or pollution using specifically designed active substrates. These sensors are very stable over time; nevertheless, their sensitivity to the temperature is well known, and different implementations have been devised to correct it, e.g., through compensation with a dual crystal. This paper deals with the effects of temperature on QCM but separates the case of uniform crystal temperature from the case of in-plane temperature gradients considering a QCM based on quartz crystals with deposited film resistors used as both RTDs and heaters. This configuration allows both an accurate temperature measurement and efficient thermal control, allowing the achievement of crystals temperatures in the order of 400 °C higher than the environment with a low power dissipation of the order of 1 W. The film resistors deposited around the electrodes allow directly measuring the average crystal temperature and directly delivering power to the crystal for thermal control. The localized delivery of the heat nevertheless also determines uncommon temperature fields on the crystal, and thus, an analysis of both the effects of temperature on the new microbalance was performed. The temperature gradient has strong effects on the frequency; therefore, along with the temperature, the thermal gradients have tobe compensated. The calibration of the QCM thermometers and the assessment of the achievable measurement accuracy were performed, as well as the determination of the frequency–temperature relationship. The comparison between frequency changes in the case of uniform temperature and those observed while using crystal heaters proved that temperature gradients have a strong effect on the crystal frequency. To identify the temperature field on the crystal surface of a QCM crystal, the gold coating of the deposited films was removed to achieve an emissivity acceptable for thermal imaging with an IR camera. Moreover, image processing for emissivity correction was developed. In order to correlate the temperature gradient with the frequency variation, a test campaign was performed to measure the frequency changes derived from different power levels delivered to the crystal heaters. From this test campaign and thermal analysis, the effect of the thermal gradient was assessed.

Using extended reality (XR) for medical training and real-time clinical support during deep space missions

Medical events can affect space crew health and compromise the success of deep space missions. To successfully manage such events, crew members must be sufficiently prepared to manage certain medical conditions for which they are not technically trained. Extended Reality (XR) can provide an immersive, realistic user experience that, when integrated with augmented clinical tools (ACT), can improve training outcomes and provide real-time guidance during non-routine tasks, diagnostic, and therapeutic procedures. The goal of this study was to develop a framework to guide XR platform development using astronaut medical training and guidance as the domain for illustration. We conducted a mixed-methods study—using video conference meetings (45 subject-matter experts), Delphi panel surveys, and a web-based card sorting application—to develop a standard taxonomy of essential XR capabilities. We augmented this by identifying additional models and taxonomies from related fields. Together, this “taxonomy of taxonomies,” and the essential XR capabilities identified, serve as an initial framework to structure the development of XR-based medical training and guidance for use during deep space exploration missions. We provide a schematic approach, illustrated with a use case, for how this framework and materials generated through this study might be employed.

Effects Of Hindlimb Unloading And Long Acting Reversible Contraception On Markers Of Mitophagy In Muscle

Spaceflight has been shown to cause severe muscle atrophy. While loss of contractile proteins has been well documented, there is little research on the effects on the mitochondria and mitophagy. Long-acting reversible contraceptives (LARC; progestin-only) will be likely be recommended for female astronauts on deep space mission, however, the impact on muscle is unknown. PURPOSE: The purpose of this study was to examine the effects of hindlimb unloading (HU) and LARC on muscle mitophagy. METHODS: Female Sprague-Dawley rats (n = 52; 4-mo-old) were singly housed and randomly assigned to placebo (PL) and LARC groups, via an implanted slow-release etonogestrel pellet (0.00ug/d vs. 0.30ug/d). A week later, animals were further randomized to weight bearing (WB) and HU groups for 6 weeks. At the end of the 6-week HU period animals were euthanized. Tissues collected and snap frozen for later analysis. Western blot analysis was run to quantify markers of mitophagy (Parkin, NIX) as well as glycolytic enzymes (GAPDH). Signal values were normalized against the loading control for each gel. Statistics were conducted using RStudio. RESULTS: Despite increasing their food intake during HU (p < 0.01), HU animals lost weight and weighed less than WB animals starting on HU week 2 (p < 0.01). Weight wet of the gastrocnemius was significantly different after HU (WB: 2.07 g +/- 0.08 vs HU: 1.58 g +/- 0.11). A significant difference was observed between the WB and HU groups for both Parkin (1.01 +/- 0.33 vs 0.74 +/- .25, p = .006) and NIX (1.10 +/- 0.38 vs 0.82 +/- 0.43, p = .040), respectively. No significant difference was found in GAPDH. LARC had no effect on mitophagy or glycolytic enzyme content. There was no significant interaction between HU and LARC on mitophagy or glycolytic markers. CONCLUSION: After 6-weeks of unloading, markers of mitophagy were significantly decreased. This could be due to either impairments in the mitophagy process or reduced enzyme content due to reduced muscle fiber size as indicated by reduced muscle weight after HU. LARC implantation did not alter the impact of HU on mitophagy markers. Further analysis into mitochondrial protein content as well as respiratory capacity will provide insight into mitochondrial health and function.

Expanding Interplanetary Transfer Opportunities from Geostationary Transfer Orbits via Earth Synchronous Orbits

Geostationary transfer orbits (GTOs) are geocentric orbits widely considered for kick-stage operations of satellites for deep space missions. A piggyback spacecraft departing from GTOs requires a low transfer cost. The type of GTO and launch timings of piggyback missions, on the other hand, are typically determined by the primary mission that carried the piggyback spacecraft. This research introduces a new transfer strategy that coordinates piggyback spacecraft’s departure timing from Earth to deep space via an Earth synchronous orbit (ESO) after departure from a GTO. It also enables the spacecraft to change its velocity direction by introducing Earth gravity assists. Connecting several GTOs and interplanetary trajectories via ESOs reduces the required for the transfers. It leads to using transfer opportunities previously considered unsuitable for missions or miniaturizing the kick motor. As a result, ESOs allow for a broader launch opportunity for deep space piggyback probes. In addition, the feasibility of ESOs is shown numerically by comparing direct and ESO-assisted transfers from GTOs to Mars with the required .

Supporting Uranus Exploration with Deployable Small Spacecraft Probes

We present a mission concept to study the capability for a parent spacecraft to transmit power and remotely manipulate a small probe spacecraft, potentially as small as a chipsat, which is a spacecraft constructed on a single printed circuit board, through a laser transmitter. This concept, referred to as sustained chipsat/CubeSat activity through transmitted electromagnetic radiation, enables the mothership to intermittently deploy probes to make distributed measurements where the use of only photovoltaic, battery, or radioisotope power sources would be infeasible. Using these probes during a long-duration deep space mission to Uranus would provide enhanced scientific measurements such as magnetic field gradients, leading to a better understanding of the ice giants, which are the least explored planets in our solar system. In this paper, we assess the feasibility of using a mothership-based laser for wireless power transfer, translation and attitude control, and communication of probes ranging from a minimal-mass chipsat to a 3U CubeSat, where U refers to a standard 10 cm CubeSat volume. We find that the best performance is achieved with an intermediate probe size, corresponding to a 0.5U CubeSat, which could capture over an order of magnitude more power than the chipsat while being agile enough to maintain attitude control using laser photon pressure.

Interstellar Propulsion Using Laser-Driven Inertial Confinement Fusion Physics

To transport a spacecraft to distances far beyond the solar heliosphere and around the planets of other stars will require advanced space propulsion systems that go beyond the existing technological state of the art. The release of fusion energy from the interaction of two low mass atomic nuclei that are able to overcome the Coulomb barrier offers the potential for ∼1011J/g specific energy release and implies that robotic missions to the nearby stars to distances of ∼5–10 ly may be possible in trip durations of the order of ∼50–100 years, travelling at cruise speeds of the order of ∼0.05–0.15 c. Such missions would be characterised with ∼kN-MN thrust levels, ∼GW-TW jet powers, ∼kW/kg-MW/kg specific powers. One of the innovative methods by which fusion reactions can be ignited is via the impingement of laser beams onto an inertial confinement fusion capsule, imploding it to a thermonuclear state. This paper gives an overview of the physics of inertial confinement fusion and the interaction of a laser beam with a capsule to include the simulation of a 1D particle-in-cell code calculation to illustrate the effects. In the application to deep space missions, various spacecraft concepts from the literature are discussed, and the range of values assumed for the pulse frequency, burn fraction and areal density appropriate for the mission are presented. It is concluded that advanced space propulsion via inertial confinement fusion is a plausible part of our future, provided that experimental validation of ignition is on the horizon and numerical models for feasibility concepts are developed to high fidelity and on a consistent basis.

Effects of microgravity on cryogenic spray quenching of a simulated propellant storage tank with enhancement by surface coating and flow pulsing

In-space cryogenic propulsion will play a vital role in space exploration mission to the Moon and future mission to the Mars. The enabling of in-space cryogenic rocket engines and the Lower-Earth-Orbit (LEO) cryogenic fuel depots for these future manned and robotic space exploration missions begins with the technology development of advanced cryogenic thermal-fluid management systems for the propellant transfer line and storage tank system.One of the key thermal-fluid management operations is the chilldown of the propellant storage tank. As a result, highly energy efficient, breakthrough concepts for quenching heat transfer to conserve and minimize the cryogen consumption during chilldown have become the focus of engineering research and development, especially for the deep-space mission to Mars. In this paper, we introduce such thermal transport concepts and demonstrate their feasibility in space for cryogenic propellant storage tank chilldown in a simulated space microgravity condition on board an aircraft flying a parabolic trajectory. In order to maximize the storage tank chilldown thermal efficiency for the least amount of required cryogen consumption, the breakthrough quenching heat transfer concepts developed include the combination of cryogenic spray quenching cooling, Teflon thin-film coating on the simulated tank surface, and spray flow pulsing. The boiling heat transfer physics that supports the concepts is clearly explained. The completed flight experiments successfully demonstrated the feasibility of the concepts and discovered that spray cooling is the most efficient cooling method for the tank chilldown in microgravity. In microgravity, the data shows that the chilldown thermal efficiency can reach 30% with Teflon coating alone. However, Teflon coating together with flow pulsing was found to substantially enhance the chilldown efficiency further to reach the 50% goal.

Применение мощных энергодвигательных систем для выполнения транспортных задач в космосе

The purpose of the research was to consider the application of high power level power and propulsion systems for different space missions. The paper gives the main components of high power level nuclear power and propulsion systems as well as their architecture options and integration solutions. Within the research, we set requirements to characteristics of high power level power and propulsion systems of advanced spacecraft aimed for different transport missions in near-Earth and deep space, analyzed efficiency of nuclear power and propulsion systems applied for transport missions in comparison with conventional chemical propulsion systems. Findings of the research show that high power level power and propulsion systems have the following advantages in comparison with conventional chemical propulsion systems: increase of payload mass; possibility of direct flights (without gravitational maneuvers) to deep space objects; ensuring power supply of target equipment and communication systems at a qualitatively higher level.

Resolved imaging of exoplanets with the solar gravitational lens

ABSTRACT We discuss the feasibility of direct multipixel imaging of exoplanets with the solar gravitational lens (SGL) in the context of a realistic deep space mission. For this, we consider an optical telescope, placed in the image plane that forms in the strong interference region of the SGL. We consider an Earth-like exoplanet located in our immediate stellar neighbourhood and model its characteristics using our own Earth. We estimate photon fluxes from such a compact, extended, resolved exoplanet. This light appears in the form of an Einstein ring around the Sun, seen through the solar corona. The solar corona background contributes a significant amount of stochastic noise and represents the main noise source for observations utilizing the SGL. We estimate the magnitude of this noise. We compute the resulting signal-to-noise ratios (SNRs) and related integration times that are needed to perform imaging measurements under realistic conditions. It is known that deconvolution, removing the blur due to the SGL’s spherical aberration substantially decreases the SNR. Our key finding is that this ‘penalty’ is significantly mitigated when sampling locations in the image plane (image pixels) remain widely spaced. Consequently, we conclude that an imaging mission is challenging but feasible, using technologies that are either already available or in active development. Under realistic conditions, high-resolution imaging of Earth-like exoplanets in our galactic neighbourhood requires only weeks or months of integration time, not years as previously thought: a high quality 1000 × 1000 pixel image of an Earth-like planet at Proxima Centauri could be obtained with SNR &amp;gt; 10 using approximately 14 months of integration time.

Health, hygiene, and microbial monitoring during long-duration space simulations

The significance of the human-microbe relationship is amplified in long duration space exploration (LDSE), where isolated and confined microbial environments degenerate space habitat integrity, compromise planetary protection goals, and have largely unknown and potentially deleterious effects on astronaut health. While environmental surveillance is assumed to be a key component of future deep space missions, the optimal modality, frequency, and location of such surveillance is not yet defined. In order to investigate strategies of microbial surveillance, a series of experiments, conducted at a long-duration, isolated and confined (ICE) Mars simulation, furthered our understanding of the microbiome sampling challenges presented by food, environment, and crewmembers. Descriptive analyses revealed key considerations for microbial monitoring in future long duration space missions, including special considerations for surface sanitation, previously undocumented potential sources of food-borne toxicity, and a novel outlook on the dynamic human microbiome in isolation.

On Scaling of Hall-Effect Thrusters Using Neural Nets

Hall-effect thrusters (HETs) are widely used for modern near-Earth spacecraft propulsion and are vital for future deep-space missions. Methods of modeling HETs are developing rapidly. However, such methods are not yet precise enough and cannot reliably predict the parameters of a newly designed thruster, mostly due to the enormous computational cost of a HET plasma simulation. Another approach is to use scaling techniques based on available experimental data. This paper proposes an approach for scaling HETs using neural networks and other modern machine learning methods. The new scaling model was built with information from an extensive database of HET parameters collected from published papers. Predictions of the new scaling model are valid for the operating parameters domain covered by the database. During the design, this model can help HET developers estimate the performance of a newly designed thruster. At the stage of experimental research, the model can be used to compare the achieved characteristics of the studied thruster with the level obtained by other developers. A comparison with the state-of-the-art HET scaling model is also presented.