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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS2016

Pharmaceuticals Exposed to the Space Environment: Problems and Prospects

The NASA Human Research Program (HRP) Health Countermeasures Element maintains ongoing efforts to inform detailed risks, gaps, and further questions associated with the use of pharmaceuticals in space. Most recently, the Pharmacology Risk Report, released in 2010, illustrates the problems associated with maintaining pharmaceutical efficacy. Since the report, one key publication includes evaluation of pharmaceutical products stored on the International Space Station (ISS). This study shows that selected pharmaceuticals on ISS have a shorter shelf-life in space than corresponding terrestrial controls. The HRP Human Research Roadmap for planetary exploration identifies the risk of ineffective or toxic medications due to long-term storage during missions to Mars. The roadmap also identifies the need to understand and predict how pharmaceuticals will behave when exposed to radiation for long durations. Terrestrial studies of returned samples offer a start for predictive modeling. This paper shows that pharmaceuticals returned to Earth for post-flight analyses are amenable to a Weibull distribution analysis in order to support probabilistic risk assessment modeling. The paper also considers the prospect of passive payloads of key pharmaceuticals on sample return missions outside of Earth's magnetic field to gather additional statistics. Ongoing work in radiation chemistry suggests possible mitigation strategies where future work could be done at cryogenic temperatures to explore methods for preserving the strength of pharmaceuticals in the space radiation environment, perhaps one day leading to an architecture where pharmaceuticals are cached on the Martian surface and preserved cryogenically.

pharmacology↗
NASA NTRS1988

Penetrator role in Mars sample strategy

The application of the penetrator to a Mars Return Sample Mission (MRSM) has direct advantages to meet science objectives and mission safety. Based on engineering data and work currently conducted at Ball Aerospace Systems Division, the concept of penetrators as scientific instruments is entirely practical. The primary utilization of a penetrator for MRSM would be to optimize the selection of the sample site location and to help in selection of the actual sample to be returned to Earth. It is recognized that the amount of sample to be returned is very limited, therefore the selection of the sample site is critical to the success of the mission. The following mission scenario is proposed. The site selection of a sample to be acquired will be performed by science working groups. A decision will be reached and a set of target priorities established based on data to give geochemical, geophysical and geological information. The first task of a penetrator will be to collect data at up to 4 to 6 possible landing sites. The penetrator can include geophysical, geochemical, geological and engineering instruments to confirm that scientific data requirements at that site will be met. This in situ near real-time data, collected prior to final targeting of the lander, will insure that the sample site is both scientifically valuable and also that it is reachable within limits of the capability of the lander.

Boynton, William↗
NASA NTRS1990

Project EGRESS: The design of an assured crew return vehicle for the space station

Keeping preliminary studies by NASA in mind, an Assured Crew Return Vehicle (ACRV) was developed. The system allows the escape of one or more crew members from Space Station Freedom in case of emergency. The design of the vehicle addresses propulsion, orbital operations, reentry, landing and recovery, power and communication, and life support. In light of recent modifications in Space Station design, Project EGRESS (Earthbound Guaranteed ReEntry from Space Station) pays particular attention to its impact on Space Station operations, interfaces and docking facilities, and maintenance needs. A water landing, medium lift vehicle was found to best satisfy project goals of simplicity and cost efficiency without sacrificing the safety and reliability requirements. With a single vehicle, one injured crew member could be returned to Earth with minimal pilot involvement. Since the craft is capable of returning up to five crew members, two such permanently docked vehicles would allow full evacuation of the Space Station. The craft could be constructed entirely with available 1990 technology and launched aboard a shuttle orbiter.

Source record↗
NASA NTRS2014

Investigation of HZETRN 2010 as a Tool for Single Event Effect Qualification of Avionics Systems

NASA's future missions are focused on long-duration deep space missions for human exploration which offers no options for a quick emergency return to Earth. The combination of long mission duration with no quick emergency return option leads to unprecedented spacecraft system safety and reliability requirements. It is important that spacecraft avionics systems for human deep space missions are not susceptible to Single Event Effect (SEE) failures caused by space radiation (primarily the continuous galactic cosmic ray background and the occasional solar particle event) interactions with electronic components and systems. SEE effects are typically managed during the design, development, and test (DD&T) phase of spacecraft development by using heritage hardware (if possible) and through extensive component level testing, followed by system level failure analysis tasks that are both time consuming and costly. The ultimate product of the SEE DD&T program is a prediction of spacecraft avionics reliability in the flight environment produced using various nuclear reaction and transport codes in combination with the component and subsystem level radiation test data. Previous work by Koontz, et al.1 utilized FLUKA, a Monte Carlo nuclear reaction and transport code, to calculate SEE and single event upset (SEU) rates. This code was then validated against in-flight data for a variety of spacecraft and space flight environments. However, FLUKA has a long run-time (on the order of days). CREME962, an easy to use deterministic code offering short run times, was also compared with FLUKA predictions and in-flight data. CREME96, though fast and easy to use, has not been updated in several years and underestimates secondary particle shower effects in spacecraft structural shielding mass. Thus, this paper will investigate the use of HZETRN 20103, a fast and easy to use deterministic transport code, similar to CREME96, that was developed at NASA Langley Research Center primarily for flight crew ionizing radiation dose assessments. HZETRN 2010 includes updates to address secondary particle shower effects more accurately, and might be used as another tool to verify spacecraft avionics system reliability in space flight SEE environments.

Rojdev, Kristina↗
NASA NTRS2007

Orion Cislunar Guidance and Navigation

The Orion vehicle is being designed to provide nominal crew transport to the lunar transportation stack in low Earth orbit, crew abort prior during transit to the moon, and crew return to Earth once lunar orbit is achieved. Design of guidance and navigation algorithms to perform maneuvers in support of these functions is dependent on the support provided by navigation infrastructure, the performance of the onboard GN&C system, and the choice of trajectory maneuver methodology for outbound and return mission phases. This paper documents the preliminary integrated analyses performed by members of the Orion Orbit GN&C System team investigating the navigation update accuracy of a modern equivalent to the Apollo era ground tracking network and the expected onboard dispersion and navigation errors during a lunar mission using a linear covariance error analysis technique.

D'Souza, Christopher↗
NASA NTRS2012

Systems Engineering and Technology Considerations of a Mars Ascent Vehicle

A Mars Ascent Vehicle (MAV) systems engineering study is underway to define the driving requirements, system architecture, major risks, and required technology developments to support the launch of a rock core sample to a specified delivery orbit for later retrieval and return to Earth. The proposed MAV would essentially be a small-scale launch vehicle, the first of its kind to be launched autonomously from another planet. The MAV would be a flight element of the proposed Mars Sample Return (MSR) campaign architecture, which currently assumes a 2018 launch of the sample caching mission and a 2024 (Earth) launch date of the MAV and lander, with arrival on Mars in 2025. After 9 months on the surface the MAV would be erected and launched to a specified delivery orbit. In the delivery orbit it would release its payload, a 5 kg sphere containing the rock core sample. An orbiter would rendezvous and capture the payload, returning it to Earth a year later.

entry, descent, and landing (EDL)↗
NASA NTRS2017

Contamination Knowledge Strategy for the Mars 2020 Sample-Collecting Rover

The Mars 2020 rover will collect carefully selected samples of rock and regolith as it explores a potentially habitable ancient environment on Mars. Using the drill, rock cores and regolith will be collected directly into ultraclean sample tubes that are hermetically sealed and, later, deposited on the surface of Mars for potential return to Earth by a subsequent mission. Thorough characterization of any contamination of the samples at the time of their analysis will be essential for achieving the objectives of Mars returned sample science (RSS). We refer to this characterization as contamination knowledge (CK), which is distinct from contamination control (CC). CC is the set of activities that limits the input of contaminating species into a sample, and is specified by requirement thresholds. CK consists of identifying and characterizing both potential and realized contamination to better inform scientific investigations of the returned samples. Based on lessons learned by other sample return missions with contamination-sensitive scientific objectives, CC needs to be "owned" by engineering, but CK needs to be "owned" by science. Contamination present at the time of sample analysis will reflect the sum of contributions from all contamination vectors up to that point in time. For this reason, understanding the integrated history of contamination may be crucial for deciphering potentially confusing contaminant-sensitive observations. Thus, CK collected during the Mars sample return (MSR) campaign must cover the time period from the initiation of hardware construction through analysis of returned samples in labs on Earth. Because of the disciplinary breadth of the scientific objectives of MSR, CK must include a broad spectrum of contaminants covering inorganic (i.e., major, minor, and trace elements), organic, and biological molecules and materials.

Farley, K. A.↗
NASA NTRS1995

Vestibular plasticity following orbital spaceflight: recovery from postflight postural instability

Results of previous studies suggested that the vestibular mediated postural instability observed in astronauts upon return to earth from orbital spaceflight may be exacerbated by an increased weighting of visual inputs for spatial orientation and control of movement. This study was performed to better understand the roles of visual and somatosensory contributions to recovery of normal sensori-motor postural control in returning astronauts. Preflight and postflight, 23 astronaut volunteers were presented randomly with three trials of six sensory organization test (SOT) conditions in the EquiTest system test battery. Sagittal plane center-of-gravity (COG) excursions computed from ground reaction forces were significantly higher on landing day than preflight for those test conditions presenting sway-referenced visual and/or somatosensory orientation cues. The ratio of summed peak-to-peak COG sway amplitudes on the two sway-referenced vision tests (SOTs 3 + 6) compared to the two eyes closed tests (SOTs 2 + 5) was increased on landing day, indicating an increased reliance on visual orientation cues for postural control. The ratio of peak-to-peak COG excursions on sway-referenced surfaces (SOTs 4, 5 & 6) to an earth fixed support surfaces (SOTs 1, 2 & 3) increased even more after landing suggesting primary reliance on somatosensory orientation cues for recovery of postflight postural stability. Readaptation to sway-referenced support surfaces took longer than readaptation to sway-referenced vision. The increased reliance on visual and somatosensory inputs disappeared in all astronauts 4-8 days following return to earth.

NASA Program Space Physiology and Countermeasures↗
NASA NTRS1972

Spacecraft orientation and exposure to environment, Appendix A

Material removed from the spacecraft and returned to earth remained on the lunar surface for 31.9 lunations. None of the returned parts received the maximum 10,686 hours of exposure because of shadowing by the planar array antenna, solar panel, thermal control compartments, or other parts of the spacecraft. To determine the actual exposure of specific parts to sunlight, six series of photographs were taken. A one-fifth-scale model spacecraft was oriented to a collimated light source simulating the orientation of Surveyor with the sun. Three cameras were set up to view different parts of the spacecraft. The data obtained from these photographs permitted an evaluation of the effects of exposure to solar radiation on the camera and its parts, the surface sampling scoop, and the strut from the radar altimeter and Doppler velocity sensor.

Nickle, N. L.↗
NASA NTRS1973

The design and utilization of a spacelab for sortie missions

Consideration of the feasibility of a 'sortie' type mission in which a manned laboratory is carried into near-earth orbit for a 7- to 30-day mission and is then returned to earth for reconfiguration and subsequent reflight. The fundamental difference in approach between the proposed Spacelab and concepts previously considered for space stations is that the spacelab will remain attached to the Shuttle Orbiter during its entire mission in space. An important trend in the design approach is the introduction of structural modularity of the Spacelab. Another factor which has been a significant design consideration is the need to properly balance the Shuttle and Spacelab configuration over a wide range of aerodynamic regimes and landing conditions. Also considered are the requirements which may be placed on the laboratory by potential users in fields of science and space applications.

Lord, D. R.↗
NASA NTRS1980

SPS salvage and disposal alternatives

A wide range of salvage options exist for the satellite power system (SPS) satellite, ranging from use in and beyond geosynchronous orbit to use in low Earth orbit to return and use on Earth. The satellite might be used intact to provide for various purposes, it might be cannibalized, or it might be melted down to supply materials for space- or ground-based products. The use of SPS beyond its nominal lifetime provides value that can be deducted from the SPS capital investment cost. It is shown that the present value of the salvage value of the SPS satellites, referenced to the system initial operation data, is likely to be on the order of five to ten percent of its on-orbit capital cost. (Given a 30 year satellite lifetime and a four percent discount rate, the theoretical maximum salvage value is 30.8 percent of the initial capital cost). The SPS demonstration satellite is available some 30 years earlier than the first full-scale SPS satellite and has a likely salvage value on the order of 80 percent of its on site capital cost. In the event that it becomes desirable to dispose of either the demonstration or full-scale SPS satellite, a number of disposal options appear to exist for which intact disposal costs are less than one percent of capital costs.

Source record↗
NASA NTRS1980

Satellite power system salvage and disposal alternatives

A wide range of salvage options for the SPS satellite, ranging from use in and beyond geosynchronous orbit to use in low Earth orbit in return and use on Earth are presented. The satellite can be used intact to provide power for various purposes, it can be cannibalized or it can be melted down to supply materials for space or ground based products. The use of SPS beyond its nominal lifetime provides value that can be deducted from the SPS capital investment cost. The present value of the salvage value of the SPS satellites, referenced to the system initial operation data, is on the order of five to ten percent of its on-orbit capital cost. (Given a 30 year satellite lifetime and a four percent discount rate, the theoretical maximum salvage value is 30.8 percent of the capital cost.) The SPS demonstration satellite is available some 30 years earlier than the first full scale SPS satellite and has a salvage value on the order of 80 percent of its on-orbit capital cost. In the event that it becomes desirable to dispose of either the demonstration of full scale SPS satellite, a number of disposal options is presented for which intact disposal costs are less than one percent of capital costs.

Source record↗
NASA NTRS1990

Mars sample return missions, precursors to manned planetary exploration

Technologies and concepts applicable to eventual manned exploration of Mars, as demonstrated by the Mars Sample Return Mission, are presented. These include aerocapturing at Mars; safe and accurate descent and landing effectively using aerobraking and propulsion; launch and ascent from the Martian surface; rendezvous and docking with an orbiting return vehicle; and a safe return to earth. Critical mission elements are expected to function independently of either earth or astronaut control to ensure human safety. The Mars Rover Sample Return Mission includes such elements as autonomous functions in this unmanned mission. Based on the analyses performed and the concepts investigated, it is suggested that robotic missions are feasible for late 1990s without any major technology development being required.

Stager, D. N.↗
NASA NTRS2001

Physical-Chemical Solid Waste Processing for Space Missions at Ames Research Center

As space missions become longer in duration and reach out to more distant locations such as Mars, solids waste processing progresses from storage technologies to reclamation technologies. Current low Earth orbit technologies consist of store-and dispose to space or return to Earth. Fully regenerative technologies recycle wastes. The materials reclaimed from waste can be used to provide the basic materials to support plant growth for food including carbon dioxide, water, and nutrients. Other products can also be reclaimed from waste such as hydrocarbons and activated carbon. This poster describes development at Ames Research Center of a process to make activated carbon from space mission wastes and to make an incineration system that produces clean flue gas. Inedible biomass and feces contain hydrocarbons in a form that can be pyrolyzed and converted to activated carbon. The activated carbon can then be used to clean up contaminants from various other life support systems; in particular, the activated carbon can be used regeneratively to remove NOx from incinerator flue gas. Incinerator flue gas can also be cleaned up by the use of reductive and oxidative catalysts. A catalytic incinerator flue gas cleanup system has been developed at ARC that produces flue gas clean enough (with the exception of carbon dioxide) to meet the Space Minimum Allowable Concentration limits for human exposure.

Fisher, John W.↗
NASA NTRS2004

A Comparison of Transportation Systems for Human Missions to Mars

There are many ways to send humans to Mars. Credible technical reports can be traced to the 1950's. More recently, NASA has funded major studies that depict a broad variety of trajectories, technologies, stay times, and costs. Much of this data is still valid with direct application to today's exploration planning. This paper presents results comparing these studies with particular emphasis on the in-space transportation aspects of the mission. Specifically, comparisons are made on propulsion systems used for getting the crew and mission equipment from Earth orbit to Mars orbit, descending and ascending from the surface, and returning to Earth orbit. Areas of comparison for each of these phases include crew size, mission mass, propellant mass, delta v, specific impulse, transit time, surface stay time, aero-braking, and others. Data is analyzed to demonstrate either strong trends toward particular technologies or diverging solutions.

Bipropellants↗
NASA NTRSDate not supplied

A physician’s working group guides COVID-19 prevention in a mission critical environment

Background A team was assembled at the National Aeronautics and Space Administration’s (NASA) Johnson Space Center (JSC) to help navigate the shifting COVID-19 pandemic. Their goal was to mitigate the impact of COVID on astronauts, other essential personnel, and the human spaceflight program. This team supplemented the JSC Pandemic Incident Response Group, whose function is to set policy for the overall management of JSC’s COVID-19 mitigations for all onsite mission-essential and mission-critical activities, including health policy. Context The first mission to return to Earth from the International Space Station at the start of the pandemic returned when there was limited information about the transmission and prevention of COVID-19. The medical leadership at JSC determined that a dedicated team was required to navigate the uncharted waters of the pandemic. Description of Activities Issues tackled by this panel included: prevention of COVID-19 transmission during altitude, dive, and spacecraft training – activities that require prolonged close contact between multiple individuals who often cannot safely wear face masks; mitigating the risks of domestic and international travel for essential personnel; securing COVID-19 testing from local and foreign hospital systems; acquiring antigen and PCR analyzers for in-house testing; and the development of quarantine policies for crewed spacecraft launches and landings in Kazakhstan and the United States. The panel also provides clinical return-to-work guidance for cases of COVID-19 in essential personnel.

covid↗
NASA NTRSDate not supplied

Assessing the Oxygen Permeability of Candidate Asteroid Sample Containers With Optochemical Sensors

The Astromaterials Acquisition and Curation Office at NASA Johnson Space Center currently curates 500 mg (10%) of carbonaceous asteroid Ryugu regolith collected by the Japan Aerospace and Exploration Agency’s Hayabusa II spacecraft and returned to Earth in 2021. In September 2023, NASA’s OSIRIS-REx spacecraft returned at least 70 grams of regolith collected from the surface of Carbonaceous Asteroid Bennu. These new astromaterials collections are stored and handled in gloveboxes and desiccators that are continuously purged with ultrapure nitrogen in order to minimize contamination and alteration of extraterrestrial samples from terrestrial environments, e.g., reaction with terrestrial oxygen and water. Ito et al. have previously reported on the development of containers to transport samples between facilities in inert, sealed environments; Hayabusa2 samples allocated to investigators by JAXA’s Extraterrestrial Sample Curation Center (ESCuC) are shipped in these Facility-to-Facility Transfer Containers (FFTCs). NASA curation has also been investigating sealed containers for storage, transportation, and allocation of Bennu and Ryugu regolith in sealed anoxic environments. In order to assess the ability of candidate sample containers to maintain nitrogen environments, we have utilized optochemical sensors to measure trace oxygen levels within sealed volumes.

C J Snead↗
NASA NTRSDate not supplied

Addressing the High-Rate Deep Space Communications Shortfall in NASA’s Space Technology Mission Directorate's Envisioned Future

NASA’s Space Technology Mission Directorate (STMD) has identified key technologies needed for future crewed and robotic exploration and science missions. STMD is helping to build the civilian technology base by working with other NASA Mission Directorates, other United States government agencies, commercial industry, and academia to identify technology shortfalls and to develop plans to address them. One critical area of shortfalls lies with deep space communications and navigation. While NASA had huge success to date with the Deep Space Network (DSN), recent studies have shown that without enhancements to current systems, the DSN will be unable to support the anticipated increases in the pace of space exploration or the expected higher data rates from deep space needed soon without severely impacting other missions. High-rate communications from the Moon and beyond is needed to enable future exploration and science missions currently being developed or under consideration. For example, a robust communications infrastructure will be needed to support a sustained human presence on the Moon and its eventual industrialization. High data rate trunk lines between the Earth and the Moon are needed to reduce the number of individual links. The human exploration of Mars will also require high-rate communications between Earth and Mars. Return data rates to Earth from Mars for a single link, for example, are anticipated to be greater than 100 Mb/s; forward data rates to Mars, based on experience from the International Space Station, are anticipated to be greater than 20 Mb/s. Future deep space science missions will also require higher data rates than possible with today’s technology and the current capabilities of the DSN. To support future exploration and science needs, it will be necessary to upgrade the DSN to enhance its radio frequency (RF) capabilities. In addition, it is envisioned that NASA will gradually introduce optical communications to augment its RF systems. Optical communications will enable new science and exploration missions by providing high data rates and better navigation over long distances. This paper will briefly describe STMD’s envisioned future for deep space communications in the 2030+ timeframe and the technology roadmaps being developed for both radio frequency and optical systems.

Bernard Edwards↗