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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 757 records · Page 42

Erosion Behavior of Ti-hBN Multifunctional Coatings in A Custom-Made Planetary Test Rig at Extreme Lunar Temperatures

Spacecraft landings and takeoffs on the lunar surface, along with extreme temperature variations between day and night (-196 to 150° C), cause high-velocity dust impacts and erosion, resulting in the premature failure of structures. Ti/2 vol% hBN coatings were deposited using atmospheric (APS) and vacuum plasma spray (VPS) using cryo-milled powder feedstock to protect the structural components. The erosion performance of coatings at extreme lunar temperature regimes (-150 to 150° C) was evaluated in a custom-made planetary erosion test rig (PETR) at low (50 mph) and high impact velocities (250 mph). The mass loss of VPS coatings was reduced by 50% compared to the APS coatings and 40% compared to the Ti6Al4V substrate. The cryogenic temperature induces brittleness in the material, rendering it susceptible to extreme conditions of material loss. The particle impact-deformation behavior was captured using a high-speed camera to study the erosion mechanism. This analysis revealed chipping in substrates and brittle APS coatings, while particles rebounding and embedding were observed in VPS coatings. Energy calculations, aided by particle trajectory tracking from the high-speed camera, have conclusively shown that VPS coatings absorb 5–10% more energy than APS coatings during erosion tests. A modified erosion index was developed incorporating the fracture toughness and temperatures. New erosion models for brittle and ductile target materials are proposed for developing erosion-resistant material systems.

Abhijith Kunneparambil Sukumaran↗

Space suit extravehicular hazards protection development

Presented is an overview of the development of the integral thermal/micrometeoroid garment (ITMG) used for protection of a space-suited crewmember from hazards of various extravehicular environments. These hazard conditions can range from thermal extremes, meteoroid and debris particles, and radiation conditions in near-earth orbits and free space to sand and dust environments encountered on lunar and planetary surfaces. Representative ITMG materials cross-section layups are identified and described for various space suit configurations ranging from the Gemini program to planned protective requirements and considerations for anticipated Space Station EV operations.

Kosmo, Joseph J.↗

Space suit extravehicular hazards protection development

Presented is an overview of the development of the integral thermal/micrometeoroid garment (ITMG) used for protection of a space-suited crewmember from hazards of various extravehicular environments. These hazard conditions can range from thermal extremes, meteoroid and debris particles, and radiation conditions in near-earth orbits and free space to sand and dust environments encountered on lunar or planetary surfaces. Representative ITMG materials cross-section layups are identified and described for various space-suit configurations ranging from the Gemini Program to planned protective requirements and considerations for anticipated Space Station EV operations.

Kosmo, Joseph J.↗

What Goes into a Shot at the National Ignition Facility?

Take a peek inside the National Ignition Facility, the world’s largest and most energetic laser, to see how we develop and execute some of the most complex experiments conducted anywhere. This one-of-a-kind facility was funded by the National Nuclear Security Administration to keep the nation’s nuclear stockpile safe, secure and effective. We also use the extreme conditions produced by NIF to study the science behind fusion ignition and to explore astrophysical phenomena such as supernovae, black holes and planetary interiors.

36 MATERIALS SCIENCE↗

Novel Material for Future Spacecrafts

Outside earth's protective magnetosphere crew members and sensitive equipment need to be protected against two primary radiation sources, namely Galactic Cosmic Rays (GCR) and Solar Energetic Particles (SEP). For planetary missions, this combination of radiation particles could result in doses that are higher than the allowable level currently permitted for low-earth orbit manned missions. This SBIR project aims to develop a multifunctional and lightweight composite material that not only provides sufficient radiation shielding but also provides sufficient structural integrity to be considered as a spacecraft material. This presentation will discuss the deep space radiation problem and the material based solutions being proposed by BAE SYS scientists to overcome this problem. The presentation will focus on the initiative taken by BAE SYS scientists to proactively engage and team with experts at NASA, small business, and other federal laboratories to develop and test a dual phase composite material. The presentation will also highlight the potential benefits to our customer, NASA and also to BAE SYS.

Sen, Subbayu↗

Eva Physiology, Systems, and Performance (EPSP) Project Overview

Extravehicular activity (EVA) is any activity performed by astronauts outside their space vehicle or habitat. EVA may be performed on orbit, such as outside the Space Shuttle or the International Space Station, or on a planetary surface such as Mars or on the moon. Astronauts wear a pressurized suit that provides environmental protection, mobility, life support, and communications while they work in the harsh conditions of a microgravity environment. Exploration missions to the moon and Mars may last many days and will include many types of EVAs; exploration, science, construction and maintenance. The effectiveness and success of these EVA-filled missions is dependent on the ability to perform tasks efficiently. The EVA Physiology, Systems and Performance (EPSP) project will conduct a number of studies to understand human performance during EVA, from a molecular level to full-scale equipment and suit design aspects, with the aim of developing safe and efficient systems for Exploration missions and the Constellation Program. The EPSP project will 1) develop Exploration Mission EVA suit requirements for metabolic and thermal loading, optional center of gravity location, biomedical sensors, hydration, nutrition, and human biomedical interactions; 2) develop validated EVA prebreathe protocols that meet medical, vehicle, and habitat constraints while minimizing crew time and thus increasing EVA work efficiency; and 3) define exploration decompression sickness (DCS) risks, policy, and mission success statistics and develop a DCS risk definition report.

Gernhardt, Michael L.↗

Sample Caching Subsystem

A paper describes the Sample Caching Subsystem (SCS), a method for storing planetary core and soil samples in a container that seals the samples away from the environment to protect the integrity of the samples and any organics they might contain. This process places samples in individual sleeves that are sealed within a container for use by either the current mission or by following missions. A sample container is stored with its sleeves partially inserted. When a sample is ready to be contained, a transfer arm rotates over and grasps a sleeve, pulls it out of the container from below, rotates over and inserts the sleeve into a funnel where it is passively locked into place and then released from the arm. An external sampling tool deposits the sample into the sleeve, which is aligned with the tool via passive compliance of the funnel. After the sampling tool leaves the funnel, the arm retrieves the sleeve and inserts it all the way into the sample container. This action engages the seal. Full containers can be left behind for pick-up by subsequent science missions, and container dimensions are compatible for placement in a Mars Ascent Vehicle for later return to Earth.

Backes, Paul G.↗

Heat Shield for Extreme Entry Environment Technology (HEEET)

The Heat Shield for Extreme Entry Environment Technology (HEEET) project seeks to mature a game changing Woven Thermal Protection System (TPS) technology to enable in situ robotic science missions recommended by the NASA Research Council Planetary Science Decadal Survey committee. Recommended science missions include Venus probes and landers; Saturn and Uranus probes; and high-speed sample return missions.

Venkatapathy, Ethiraj↗

In Situ Small Spacecraft Missions Utilizing Heatshield for Extreme Entry Environments Technology

There is considerable interest in utilizing Small Spacecraft beyond low Earth orbit. In November of 2018, successful data relay operations of the MarCO CubeSats during the entry, descent, and landing (EDL) of the Mars InSight mission showed the viability of using CubeSats for interplanetary missions. Additional testament to the promise of Small Spacecraft class rideshare missions is the upcoming Artemis-1 flight test that will launch thirteen 6U CubeSats, as well as the establishment of NASA’s SIMPLEx program which will conduct stand-alone planetary science missions that launch with a primary payload. It is anticipated that continued innovations in Small Spacecraft capabilities combined with small EDL systems will expand the range of potential missions to allow for in situ investigations. Recently, NASA invested in the development of a new, efficient and capable ablative thermal protection system (TPS), utilizing 3-D Weaving. The new dual layer TPS, Heatshield for Extreme Entry Environment Technology (HEEET), is tailorable, scalable, robust, mass efficient and capable of supporting in situ missions across the solar system. Combining the HEEET entry system with innovative Small Spacecraft technology will substantially expand the range of Small Spacecraft mission applications by offering the capability for high speed entry or aerocapture at destinations with atmospheres. This paper will describe the HEEET aeroshell system and highlight various mission concepts including a dual technology demonstration mission that is under development and other concepts to deliver instruments for planetary science.

Heatshield↗

Understanding Fire Through Improved Technology

Aztec(TradeMark) is the commercial name for Southwest Sciences laser. The laser has coarse tuning ranges of 10 nanometers (nm) to 30 nm at wavelengths ranging from 630 nm to 2,300 nm, making it the only commercially available external cavity diode laser with wavelengths beyond 1,650 nm. The laser's high-speed tuning in both coarse and fine wavelength regimes allows for increased trace gas detection. With the automated coarse tuning option, the Aztec sweeps through its wavelength range in less than 1 millisecond. While some diode lasers can only detect one type, or species, of a trace gas, the Aztec's broad wavelength tuning provides access to multiple trace gas species. The Aztec has a wide range of applications for both NASA and commercial users, from protecting astronauts in space to improving combustion processes on Earth. It may serve as a new tool for planetary exploration, as it can detect a wide range of multiple gas species in planetary atmospheres. The laser could optically detect gaseous indicators of incipient fires on the International Space Station and Space Shuttle, as well as detect low concentrations of potentially toxic gases in spacecraft crew habitats. The laser could also provide more accurate fire detection in aircraft cargo compartments. Since the Aztec can detect several gases that only evolve during an actual fire, its implementation could reduce the large number of commercial aircraft landings that currently occur due to false alarms. Other applications include environmental and industrial process monitoring.

Source record↗

Human Space Exploration

The Mars probe, launched by India a few months ago, is on its way to Mars. At this juncture, it is appropriate to talk about the opportunities presented to us for the Human Exploration of Mars. I am planning to highlight some of the challenges to take humans to Mars, descend, land, stay, ascend and return home safely. The logistics of carrying the necessary accessories to stay at Mars will be delivered in multiple stages using robotic missions. The primary ingredients for human survival is air, water, food and shelter and the necessity to recycle the primary ingredients will be articulated. Humans have to travel beyond the van Allen radiation belt under microgravity condition during this inter‐planetary travel for about 6 months minimum one way. The deconditioning of human system under microgravity conditions and protection of humans from Galactic cosmic radiation during the travel should be taken into consideration. The multi‐disciplinary effort to keep the humans safe and functional during this journey will be addressed.

Jeevarajan, Antony↗

Entry Systems Modeling and Ground Testing: Enabling Flight Performance and Risk Reduction

Entry, Descent, and Landing (EDL) comprise a relatively small portion of a mission’s timeline, however, it is typically among the largest risks. Flying through a body’s atmosphere reliably and accurately – from orbit to ground or via aerocapture – is a critical step toward successful in situ exploration. This exhibit will highlight EDL simulation and ground test capabilities, both existing and under development, that could support mission design, risk reduction, and post-flight analysis for Planetary Science mission concepts displayed in the 2023 SMD Planetary Science Technology Showcase.

Entry Systems↗

Pterodactyl: Thermal Protection System for Integrated Control Design of a Mechanically Deployed Entry Vehicle

The need for precision landing of high mass payloads on Mars and the return of sensitive samples from other planetary bodies to specific locations on Earth is driving the development of an innovative NASA technology referred to as the Deployable Entry Vehicle (DEV). A DEV has the potential to deliver an equivalent science payload with a stowed diameter 3 to 4 times smaller than a traditional rigid capsule configuration. However, the DEV design does not easily lend itself to traditional methods of directional control. The NASA Space Technology Mission Directorate (STMD)’s Pterodactyl project is currently investigating the effectiveness of three different Guidance and Control (G&C) systems – actuated flaps, Center of Gravity (CG) or mass movement, and Reaction Control System (RCS) – for use with a DEV using the Adaptable, Deployable, Entry, and Placement Technology (ADEPT) design. This paper details the Thermal Protection System (TPS) design and associated mass estimation efforts for each of the G&C systems. TPS is needed for the nose cap of the DEV and the flaps of the actuated flap control system. The development of a TPS selection, sizing, and mass estimation method designed to deal with the varying requirements for the G&C options throughout the trajectory is presented. The paper discusses the methods used to i) obtain heating environments throughout the trajectory with respect to the chosen control system and resulting geometry; ii) determine a suitable TPS material; iii) produce TPS thickness estimations; and, iv) determine the final TPS mass estimation based on TPS thickness, vehicle control system, vehicle structure, and vehicle payload.

Hays, Zane B.↗

Managing Space Radiation Risks On Lunar and Mars Missions: Risk Assessment and Mitigation

Radiation-induced health risks are a primary concern for human exploration outside the Earth's magnetosphere, and require improved approaches to risk estimation and tools for mitigation including shielding and biological countermeasures. Solar proton events are the major concern for short-term lunar missions (<60 d), and for long-term missions (>60 d) such as Mars exploration, the exposures to the high energy and charge (HZE) ions that make-up the galactic cosmic rays are the major concern. Health risks from radiation exposure are chronic risks including carcinogenesis and degenerative tissue risks, central nervous system effects, and acute risk such as radiation sickness or early lethality. The current estimate is that a more than four-fold uncertainty exists in the projection of lifetime mortality risk from cosmic rays, which severely limits analysis of possible benefits of shielding or biological countermeasure designs. Uncertainties in risk projections are largely due to insufficient knowledge of HZE ion radiobiology, which has led NASA to develop a unique probabilistic approach to radiation protection. We review NASA's approach to radiation risk assessment including its impact on astronaut dose limits and application of the ALARA (As Low as Reasonably Achievable) principle. The recently opened NASA Space Radiation Laboratory (NSRL) provides the capability to simulate the cosmic rays in controlled ground-based experiments with biological and shielding models. We discuss how research at NSRL will lead to reductions in the uncertainties in risk projection models. In developing mission designs, the reduction of health risks and mission constraints including costs are competing concerns that need to be addressed through optimization procedures. Mitigating the risks from space radiation is a multi-factorial problem involving individual factors (age, gender, genetic makeup, and exposure history), operational factors (planetary destination, mission length, and period in the solar cycle), and shielding characteristics (materials, mass, and topology). We review optimization metrics for radiation protection including scenarios that integrate biophysics models of radiation risks, operational variables, and shielding design tools needed to assess exploration mission designs. We discuss the application of a crosscutting metric, based on probabilistic risk assessment, to lunar and Mars mission trade studies including the assessment of multi-factorial problems and the potential benefits of new radiation health research strategies or mitigation technologies.

Cucinotta, F. A.↗

Managing Space Radiation Risks on Lunar and Mars Missions: Risk Assessment and Mitigation

Radiation-induced health risks are a primary concern for human exploration outside the Earth's magnetosphere, and require improved approaches to risk estimation and tools for mitigation including shielding and biological countermeasures. Solar proton events are the major concern for short-term lunar missions (<60 d), and for long-term missions (>60 d) such as Mars exploration, the exposures to the high energy and charge (HZE) ions that make-up the galactic cosmic rays are the major concern. Health risks from radiation exposure are chronic risks including carcinogenesis and degenerative tissue risks, central nervous system effects, and acute risk such as radiation sickness or early lethality. The current estimate is that a more than four-fold uncertainty exists in the projection of lifetime mortality risk from cosmic rays, which severely limits analysis of possible benefits of shielding or biological countermeasure designs. Uncertainties in risk projections are largely due to insufficient knowledge of HZE ion radiobiology, which has led NASA to develop a unique probabilistic approach to radiation protection. We review NASA's approach to radiation risk assessment including its impact on astronaut dose limits and application of the ALARA (As Low as Reasonably Achievable) principle. The recently opened NASA Space Radiation Laboratory (NSRL) provides the capability to simulate the cosmic rays in controlled ground-based experiments with biological and shielding models. We discuss how research at NSRL will lead to reductions in the uncertainties in risk projection models. In developing mission designs, the reduction of health risks and mission constraints including costs are competing concerns that need to be addressed through optimization procedures. Mitigating the risks from space radiation is a multi-factorial problem involving individual factors (age, gender, genetic makeup, and exposure history), operational factors (planetary destination, mission length, and period in the solar cycle), and shielding characteristics (materials, mass, and topology). We review optimization metrics for radiation protection including scenarios that integrate biophysics models of radiation risks, operational variables, and shielding design tools needed to assess exploration mission designs. We discuss the application of a crosscutting metric, based on probabilistic risk assessment, to lunar and Mars mission trade studies including the assessment of multi-factorial problems and the potential benefits of new radiation health research strategies or mitigation technologies.

Cucinotta, F. A.↗

Managing Space Radiation Risks on Lunar and Mars Missions: Risk Assessment and Mitigation

Radiation-induced health risks are a primary concern for human exploration outside the Earth's magnetosphere, and require improved approaches to risk estimation and tools for mitigation including shielding and biological countermeasures. Solar proton events are the major concern for short-term lunar missions (<60 d), and for long-term missions (>60 d) such as Mars exploration, the exposures to the high energy and charge (HZE) ions that make-up the galactic cosmic rays are the major concern. Health risks from radiation exposure are chronic risks including carcinogenesis and degenerative tissue risks, central nervous system effects, and acute risk such as radiation sickness or early lethality. The current estimate is that a more than four-fold uncertainty exists in the projection of lifetime mortality risk from cosmic rays, which severely limits analysis of possible benefits of shielding or biological countermeasure designs. Uncertainties in risk projections are largely due to insufficient knowledge of HZE ion radiobiology, which has led NASA to develop a unique probabilistic approach to radiation protection. We review NASA's approach to radiation risk assessment including its impact on astronaut dose limits and application of the ALARA (As Low as Reasonably Achievable) principle. The recently opened NASA Space Radiation Laboratory (NSRL) provides the capability to simulate the cosmic rays in controlled ground-based experiments with biological and shielding models. We discuss how research at NSRL will lead to reductions in the uncertainties in risk projection models. In developing mission designs, the reduction of health risks and mission constraints including costs are competing concerns that need to be addressed through optimization procedures. Mitigating the risks from space radiation is a multi-factorial problem involving individual factors (age, gender, genetic makeup, and exposure history), operational factors (planetary destination, mission length, and period in the solar cycle), and shielding characteristics (materials, mass, and topology). We review optimization metrics for radiation protection including scenarios that integrate biophysics models of radiation risks, operational variables, and shielding design tools needed to assess exploration mission designs. We discuss the application of a crosscutting metric, based on probabilistic risk assessment, to lunar and Mars mission trade studies including the assessment of multi-factorial problems and the potential benefits of new radiation health research strategies or mitigation technologies.

Cucinotta, F. A.↗

Aerogel Composites for Aerospace Thermal Protection

Aerogel composites formed by infiltrating organic and/or inorganic aerogels into fiber matrix materials enable us to exploit the low thermal conductivity and low density of aerogels while maintaining the strength, structure and other useful properties of a porous fiber matrix. New materials for extreme heating ranges are needed to insulate future spacecraft against the extreme heat of planetary atmospheric entry, but the insulation mass must be minimized in order to maximize the payload. A reusable system passively insulates to survive heating unchanged for relatively low heating. Ablators, which sacrifice mass to control heating, are used to protect vehicles against more extreme heating for a single use thermal protection system (TPS). Aerogel composites were fabricated and tested for spacecraft thermal protection. The high-temperaturey high heat flux tests described in this paper were performed in NASA Ames arc-jet facilities to simulate spacecraft atmospheric entry, and include heating conditions predicted for the forebody and backshell of the Mars Science Lander (MSL) entry probe. The aerogel composites tested showed excellent thermal performance in the arc-jet tests, functioning both as reusuable insulation under lower heat fluxes, and as ablative aerogels under the extreme heating predicted for the MSL forebody.

White, Susan↗

Pioneer Venus small probes net flux radiometer experiment

The University of Wisconsin net flux experiment on the Pioneer Venus mission investigated the distribution of radiative energy deposition and loss which drives atmospheric circulation on Venus. The instrument used an external sensor and a novel method of chopping to measure the net flux of solar and planetary radiation during descent through the thick Venus atmosphere. The sensor, consisting of a high temperature flux plate detector and protective diamond windows, was designed to make accurate flux measurements while exposed to the severe Venus environment.

Sromovsky, L. A.↗