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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

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At least 397 records · Page 22

Riding the Banzai Pipeline at Jupiter: Balancing Low Delta-V and Low Radiation to Reach Europa

Europa's tantalizing allure as a possible haven for life comes cloaked in a myriad of challenges for robotic spacecraft exploration. Not only are the propulsive requirements high and the solar illumination low, but the radiation environment at Jupiter administers its inexorable death sentence on any electronics dispatched to closely examine the satellite. So to the usual trades of mass, delta-V, and cost, we must add radiation dose, which tugs the trajectory solution in a contrary direction. Previous studies have concluded that adding radiation shielding mass is more efficient than using ?V to reduce the exposure time, but that position was recently challenged by a study focusing on delivering simple landers to the Europa surface. During this work, a new trajectory option was found to occupy a strategic location in the delta-V/radiation continuum - we call it the "Banzai pipeline" due to the visual similarity with the end-on view down a breaking wave, as shown in the following figures.

McElrath, Timothy P.↗

Salt Pill Design and Fabrication for Adiabatic Demagnetization Refrigerators

The performance of an adiabatic demagnetization refrigerator (ADR) is critically dependent on the design and construction of the salt pills that produce cooling. In most cases, the primary goal is to obtain the largest cooling capacity at the low temperature end of the operating range. The realizable cooling capacity depends on a number of factors, including refrigerant mass, and how efficiently it absorbs heat from the various instrument loads. The design and optimization of "salt pills" for ADR systems depend not only on the mechanical, chemical and thermal properties of the refrigerant, but also on the range of heat fluxes that the salt pill must accommodate. Despite the fairly wide variety of refrigerants available, those used at very low temperature tend to be hydrated salts that require a dedicated thermal bus and must be hermetically sealed, while those used at higher temperature - greater than about 0.5 K - tend to be single-­‐ or poly-­‐crystals that have much simpler requirements for thermal and mechanical packaging. This paper presents a summary of strategies and techniques for designing, optimizing and fabricating salt pills for both low-­‐ and mid-­‐temperature applications.

sub-kelvin cooling↗

The Lightweight Integrated Solar Array and anTenna (LISA-T) Big Power for Small Spacecraft

NASA is developing a space power system using lightweight, flexible photovoltaic devices originally developed for use here on Earth to provide low cost power for spacecraft. The Lightweight Integrated Solar Array and anTenna (LISA-T) is a launch stowed, orbit deployed array on which thin-film photovoltaic and antenna elements are embedded. The LISA-T system is deployable, building upon NASA's expertise in developing thin-film deployable solar sails such the one being developed for the Near Earth Asteroid Scout project which will fly in 2018. One of the biggest challenges for the NEA Scout, and most other spacecraft, is power. There simply isn't enough of it available, thus limiting the range of operation of the spacecraft from the Sun (due to the small surface area available for using solar cells), the range of operation from the Earth (low available power with inherently small antenna sizes tightly constrain the bandwidth for communication), and the science (you can only power so many instruments with limited power). The LISA-T has the potential to mitigate each of these limitations, especially for small spacecraft. Inherently, small satellites are limited in surface area, volume, and mass allocation; driving competition between their need for power and robust communications with the requirements of the science or engineering payload they are developed to fly. LISA-T is addressing this issue, deploying large-area arrays from a reduced volume and mass envelope - greatly enhancing power generation and communications capabilities of small spacecraft and CubeSats. The problem is that these CubeSats can usually only generate between 7W and 50W of power. The power that can be generated by the LISA-T ranges from tens of watts to several hundred watts, at a much higher mass and stowage efficiency. A matrix of options are in development, including planar (pointed) and omnidirectional (non-pointed) arrays. The former is seeking the highest performance possible while the latter is seeking GN&C simplicity. Options for leveraging both high performance, 'typical cost' triple junction thin-film solar cells as well as moderate performance, low cost cells are being developed. Alongside, UHF (ultrahigh frequency), S-band, and X-band antennas are being integrated into the array to move their space claim away from the spacecraft and open the door for more capable multi-element antenna designs such as those needed for spherical coverage and electronically steered phase arrays.

Space Exploration↗

Infrared Free Space Communication - The Autonomous Testing of Free Space Infrared Communication

Fiber optics has been a winning player in the game of high-speed communication and data transfer in cable connections. Yet, in free space RF has been the repeated choice of communication medium of the space industry. Investigating the benefits of free space optical communication over radio frequency is worthwhile. An increase in science data rate return capabilities could occur if optical communication is implemented. Optical communication systems also provide efficiencies in power, mass, and volume over RF systems1. Optical communication systems have been demonstrated from a satellite in orbit with the moon to earth, and resulted in the highest data rates ever seen through space (622Mbps)2. Because of these benefits, optical communication is far superior to RF. The HiDRA (High Data Rate Architecture) project is researching Passive Misalignment Mitigation of Dynamic Free Apace Optical Communication Links. The goal of this effort is to enable gigabit per second transmission of data in short range dynamic links (less than 100 meters). In practice this would enhance data rates between sites on the International Space Station with minimal size, weight, and power requirements. This paper will focus on an autonomous code and a hardware setup that will be used to fulfill the next step in the research being conducted. The free space optical communications pointing downfalls will be investigated. This was achieved by creating 5 python programs and a top-level code to automate this test.

Heldman, Christopher↗

Earth to Orbit Beamed Energy Experiment

As a means of primary propulsion, beamed energy propulsion offers the benefit of offloading much of the propulsion system mass from the vehicle, increasing its potential performance and freeing it from the constraints of the rocket equation. For interstellar missions, beamed energy propulsion is arguably the most viable in the near- to mid-term. A near-term demonstration showing the feasibility of beamed energy propulsion is necessary and, fortunately, feasible using existing technologies. Key enabling technologies are large area, low mass spacecraft and efficient and safe high power laser systems capable of long distance propagation. NASA is currently developing the spacecraft technology through the Near Earth Asteroid Scout solar sail mission and has signed agreements with the Planetary Society to study the feasibility of precursor laser propulsion experiments using their LightSail-2 solar sail spacecraft. The capabilities of Space Situational Awareness assets and the advanced analytical tools available for fine resolution orbit determination now make it possible to investigate the practicalities of an Earth-to-orbit Beamed Energy eXperiment (EBEX) - a demonstration at delivered power levels that only illuminate a spacecraft without causing damage to it. The degree to which this can be expected to produce a measurable change in the orbit of a low ballistic coefficient spacecraft is investigated. Key system characteristics and estimated performance are derived for a near term mission opportunity involving the LightSail-2 spacecraft and laser power levels modest in comparison to those proposed previously. While the technology demonstrated by such an experiment is not sufficient to enable an interstellar precursor mission, if approved, then it would be the next step toward that goal.

CubeSat↗

Overview of the 6m HIAD Inflatable Structure and Flexible TPS Static Load Test Series

To support NASAs long term goal of landing humans on Mars, technologies which enable the landing of heavy payloads are being developed. Current entry, decent, and landing technologies are not practical for this class of payloads due to geometric constraints dictated by current launch vehicle fairing limitations. Therefore, past and present technologies are now being explored to provide a mass and volume efficient solution to atmospheric entry, including Hypersonic Inflatable Aerodynamic Decelerators (HIADs). At the beginning of 2014, a 6m HIAD inflatable structure with an integrated flexible thermal protection system (TPS) was subjected to a static load test series to verify the designs structural performace. The 6m HIAD structure was constructed in a stacked toroid configuration using nine inflatable torus segments composed of fiber reinforced thin films, which were joined together using adhesives and high strength textile woven structural straps to help distribute the loads throughout the inflatable structure. The 6m flexible TPS was constructed using multiple layers of high performance materials to protect the inflatable structure from heat loads that would be seen during atmospheric entry. To perform the static load test series, a custom test fixture was constructed. The fixture consisted of a structural tub rim with enough height to allow for displacement of the inflatable structure as loads were applied. The bottom of the tub rim had an airtight seal with the floor. The centerbody of the inflatable structure was attached to a pedestal mount as seen in Figure 1. Using an impermeable membrane seal draped over the test article, partial vacuum was pulled beneath the HIAD, resulting in a uniform static pressure load applied to the outer surface. During the test series an extensive amount of instrumentation was used to provide many data sets including: deformed shape, shoulder deflection, strap loads, cord loads, inflation pressures, and applied static load.In this overview, the 6m HIAD static load test series will be discussed in detail, including the 6m HIAD inflatable structure and flexible TPS design, test setup and execution, and finally initial results and conclusions from the test series.

TPS↗

An Inflatable L-Band Microstrip SAR Array

Inflatable structures have been identified as one of the enabling technologies to achieve low mass, high packaging efficiency, and reliable deployment for future NASA spaceborne synthetic aperture radar (SAR) array antennas.

L-band↗

Characterization and Testing of Copper-Nickel Electroplated 3D Printed Parts for Space Flight Applications

3D printing enables novel designs which are impossible to replicate with conventional machining. The process involves 3D printing components from a polymer using a standard resin-based printing process, then electroplating the parts with a thin layer of copper-nickel. Initial results have shown these electroplated components have increased structural strength, while being less expensive; less massive; and can be made faster compared to conventional CNC machining. The focus and metric of success was to qualify this process and to answer the question if the 3D printed electroplated parts can be fabricated in a more cost, mass and schedule efficient manor compared to traditional CNC machining. Also, to determine if using this method will cause parts to have contamination issues or if parts can survive space environment testing. This was accomplished by conducting several critical tests such as outgassing, material testing and thermal cycling. In addition, this method is being used to develop a practical structural application for KArLE (Potassium Argon Laser Experiment).

3-D Printing↗

Mars Sample Return and The Capture, Containment, and Return System New Design and Path To 2027 Launch

The Mars Sample Return (MSR) campaign is one of the most ambitious and complex exoplanet scientific exploration missions currently underway. With the participation of NASA, ESA, and a large number of industry partners, MSR aims to bring back Martian rock and atmosphere samples with the goal of answering key questions about Mars’ geological, climatological, and (potentially) biological evolution. To accomplish this ambitious goal, the campaign relies on three distinct flight elements and a ground element. The Earth Return Orbiter (ERO) mission that would host the Capture, Containment, and Return System (CCRS) is the last element of the trio. The mission would capture the orbiting sample in low Mars orbit (launched into orbit by another mission), contain it and return it to Earth, landing it at the Utah Test and Training Range (UTTR). The CCRS continues its development. Since its early architecture, several changes were adopted by the project in order to improve overall payload efficiency and reduce mass. CCRS is currently on track to achieve the next milestone, Critical Design Review, expected in late 2024. This paper will discuss the CCRS design, how the current architecture contributes to an improved mission baseline, and the next critical steps of the mission towards its launch.

Mars mission↗

NASA's Capture, Containment, and Return System: Bringing Mars Samples to Earth

The Mars Sample Return (MSR) campaign is one of the most ambitious and complex planetary science exploration missions ever pursued. With the participation of NASA, ESA, and many industry partners, MSR aims to bring Martian rock and atmosphere samples to Earth with the goal of answering key questions about Mars’ geological, climatological and, potentially, biological evolution. To accomplish this ambitious goal, the MSR campaign relies on three distinct flight elements and a ground element. The Earth Return Orbiter mission that would host the Capture, Containment, and Return System (CCRS) is the last flight element of the trio. The mission would capture the orbiting sample in low Mars orbit (launched into orbit by another mission), contain it, and return it to Earth, landing at the Utah Test and Training Range. Since its early architecture, several changes were adopted by CCRS to improve overall payload efficiency and reduce mass. This paper will discuss the CCRS design, how the current CCRS architecture contributes to an improved mission concept, and the next critical steps of the mission toward its launch.

Mars mission↗

Electrodynamic Dust Shield Coating Pattern for Solar Cells

The objective of this project is to work with NASA Glenn Research Center (GRC) to develop an optimized transparent Electrodynamic Dust Shield (EDS) to remove dust accumulated on a photovoltaic (PV) cell. The PV cell efficiency deterioration depend on the mass and size of dust particles. As the particle mass and size increases, the power output and efficiency of the PV system decreases. The EDS benefits PV systems by clearing dusts blocking the sun light from entering the PV cell. As of writing of this report, the KSC team have completed the optimization of EDS pattern, completed the assembly of the EDS test samples, and successfully demonstrated EDS clearing performance at one atmosphere and vacuum.

Jerry Wang↗

Mass Economy Evaluation for Integrated ECLSS and Propulsion Architecture

As missions in Low Earth Orbit (LEO) lengthen and extend to deep space, minimizing resupply needs becomes vital for sustaining crewed operations. Traditional life support systems depend on consumables resupplied from Earth, a method that is increasingly impractical for missions beyond LEO, such as lunar outposts or Mars transit. Long-duration missions require more efficient, autonomous systems that can recycle essential resources, particularly water and oxygen, to minimize the frequency and mass of resupply missions. The Environmental Control and Life Support System (ECLSS) is essential to such missions, with the International Space Station (ISS) serving as a testbed for advanced water recovery and partial oxygen recycling via physico-chemical methods. Yet, ECLSS and propulsion subsystems generally operate independently, despite overlapping requirements and potential areas for synergy. For instance, ECLSS byproducts, water, CO₂, and hydrogen, could be repurposed for propulsion, potentially reducing dedicated propellant mass and increasing overall system efficiency. One promising approach is to develop shared-resource architectures that integrate ECLSS with propulsion systems. This study examines the potential of such integration through the Sabatier CO₂ reduction process, focusing on water management as a key factor in system mass trade-offs. The Sabatier reaction produces water and methane from metabolic CO₂ and electrolytic hydrogen, partially closing the life support loop and providing methane, which could serve as a propellant. This integration could minimize waste, reduce resupply requirements, and enhance mission mass efficiency. A dynamic modeling framework will be used to simulate resource flows over long missions, capturing interactions between life support and propulsion. By comparing integrated versus separate system configurations, the study aims to quantify mass benefits and penalties, informing future habitat designs and trade studies for missions prioritizing autonomy and mass efficiency.

ECLSS↗

Mass Economy Evaluation for Integrated ECLSS and Propulsion Architecture

As missions in low Earth orbit (LEO) lengthen and extend to deep space, minimizing resupply needs becomes vital for sustaining crewed operations. Traditional life support systems depend on consumables resupplied from Earth, a method that is increasingly impractical for missions beyond LEO, such as lunar outposts or Mars transit. Long-duration missions require more efficient, autonomous systems that can recycle essential resources, particularly water and oxygen, to minimize the frequency and mass of resupply missions. The Environmental Control and Life Support System (ECLSS) is essential to such missions, with the International Space Station (ISS) serving as a testbed for advanced water recovery and partial oxygen recycling via physico-chemical methods. Yet, ECLSS and propulsion subsystems generally operate independently, despite overlapping requirements and potential areas for synergy. For instance, ECLSS byproducts, water, CO 2 , and hydrogen, could be repurposed for propulsion, potentially reducing dedicated propellant mass and increasing overall system efficiency. One promising approach is to develop shared-resource architectures that integrate ECLSS with propulsion systems. This study examines the potential of such integration through the Sabatier CO₂ reduction process, focusing on water management as a key factor in system mass trade-offs. The Sabatier reaction produces water and methane from metabolic CO 2 and electrolytic hydrogen, partially closing the life support loop and providing methane, which could serve as a propellant. This integration could minimize waste, reduce resupply requirements, and enhance mission mass efficiency. A dynamic modeling framework will be used to simulate resource flows over long missions, capturing interactions between life support and propulsion. By comparing integrated versus separate system configurations, the study aims to quantify mass benefits and penalties, informing future habitat designs and trade studies for missions prioritizing autonomy and mass efficiency.

ECLSS↗

Comparing Run-Out Efficiency of Fluidized Ejecta on Mars with Terrestrial and Martian Mass Movements

We broadly characterize the rheology of fluidized ejecta on Mars as it flows during its final stages of emplacement by using the concept of run-out efficiency. Run-out efficiency for ejecta can be obtained through an energy balance between the kinetic energy of the excavated ejecta, and the total work lost during its deposition. Such an efficiency is directly comparable to run-out efficiency (i.e., L/H analyzes where L is the run-out distance and H is onset height) of terrestrial and extraterrestrial mass movements. Determination of the L/H ratio is commonly used in terrestrial geology to broadly determine the type and rheology of mass movements

Barnouin-Jha, O. S.↗

Thermal Protection Materials

Thermal protection materials and systems (TPS) are required to protect a vehicle returning from space or entering an atmosphere. The selection of the material depends on the heat flux, heat load, pressure, and shear and other mechanical loads imposed on the material, which are in turn determined by the vehicle configuration and size, location on the vehicle, speed, a trajectory, and the atmosphere. In all cases the goal is to use a material that is both reliable and efficient for the application. Reliable materials are well understood and have sufficient test data under the appropriate conditions to provide confidence in their performance. Efficiency relates to the behavior of a material under the specific conditions that it encounters TPS that performs very well at high heat fluxes may not be efficient at lower heat fluxes. Mass of the TPS is a critical element of efficiency. This talk will review the major classes of TPS, reusable or insulating materials and ablators. Ultra high temperature ceramics for sharp leading edges will also be reviewed. The talk will focus on the properties and behavior of these materials.

Johnson, Sylvia M.↗

Analysis of costs of gallium arsenide and silicon solar arrays for space power applications

A parametric analysis was performed to compare the costs of silicon and gallium arsenide arrays for Earth orbital missions. The missions included electric power in low Earth orbit (LEO), electric power in geosynchronous Earth orbit (GEO), and power for electric propulsion of a LEO to GEO orbit transfer mission. Inputs to the analysis for all missions included launch and purchase costs of the array. For the orbit transfer mission, the launch and purchase costs of the electric propulsion system were added. Radiation flux as a function of altitude and rediation tolerance as a function of cell type were used to determine power degradation for each mission. Curves were generated that show the sensitivity of launch-array cost and total mission cost to a variety of input parameters for each mission. These parameters included mission duration, cover glass thickness, array specific cost, array specific mass, and solar cell efficiency. Solar concentration was considered and the sensitivities of cost to concentration ratio, concentrator costs, and concentrator mass were also evaluated. Results indicate that solar cell development should give a high priority to reducing array costs and that the development of low cost, lightweight, solar concentrators should be pursued.

Jefferies, K. S.↗