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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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NASA NTRSDate not supplied

NASA's Innovative Entry Systems and TPS Technologies Enabling Commercial Space Missions

For over six decades, the NASA Ames Entry Systems and Technology Division has been a cornerstone of U.S. space exploration, delivering critical atmospheric entry solutions since Project Mercury and now increasingly supporting the commercial space sector. The Division provides reliable entry system solutions through a unique blend of expertise, national facilities, and systems integration knowledge, a combination that is difficult to replicate outside a dedicated government entity. Consistently successful, the TS Division remains central to NASA’s exploration objectives and significantly contributes to the transfer of technology to the commercial space sector, supporting more than ten commercial space companies and supplying flight heatshields to three of them in the past five years. Its strengths in Thermal Protection System (TPS) materials, aerothermodynamics, ground test facilities, and Entry, Descent, and Landing (EDL) systems engineering drive rapid development and sustained U.S. competitiveness in space. The Division's expertise in reusable and ablative thermal protection systems, as well as mechanically deployable entry systems primarily developed for NASA missions, now benefits commercial space missions. This presentation will highlight the vision and needs of these commercial space companies, how NASA-invented technologies meet mission requirements, and how these technologies enable and distinguish their efforts.

Ethiraj Venkatapathy↗
NASA NTRS2026

A Study of Space Environment Effect on Highly Thermally Conductive Hybrid Carbon Fiber Polymer Composites

A set of novel highly thermally conductive hybrid carbon fiber (CF) polymer composites has been developed for lightweight thermal radiator applications in space missions. This study investigates the effects of the space environment on these materials following exposure in low-Earth orbit (LEO) during the Materials International Space Station Experiment (MISSE)-17 flight mission, where samples experienced 159 days of combined atomic oxygen (AO), ultraviolet (UV) radiation, high vacuum, space radiation and thermal cycling. Post-flight characterization included weight loss, surface morphology, thermo-optical properties, molecular structures, glass transition temperature, thermal degradation and thermal conductivity analyses. The pyrolytic graphite sheet (PGS) samples exhibited negligible weight loss, stable thermo-optical property, and only minor oxidation signature on the exposed surface. Although AO erosion of the epoxy polymer matrix was evident, carbon nanotube (CNT)-infused PGS/CF epoxy composites retained high thermal emissivity and preserved their high thermal conductivities. These results demonstrate that the novel highly thermally conductive hybrid CF composites possess strong environmental resilience and are promising candidates for lightweight thermal radiators and thermal management components in future space exploration missions.

Space Environment↗
NASA NTRS1990

Solar Array Automation Limitations

Significant progress in the automation of the spacecraft electrical power systems has been made within the past few years. This is especially important with the development of the space station and the increasing demand on the electrical power systems for future satellites. The key element of the spacecraft power system, the solar arrays which supply the power, will have to grow to supply many tens of kilowatts of power within the next twenty years. This growth will be accompanied by the problems associated with large distributed power systems. The growth of the arrays, the on-array management problems and potential solutions to array degradation or failure are discussed. Multilowatt arrays for unmanned spacecraft with comments on the implications of array degradation for manned spacecraft are discussed.

Terry M Trumble↗
NASA NTRS2014

Controllers for Battery Chargers and Battery Chargers Therefrom

A controller for a battery charger that includes a power converter has parametric sensors for providing a sensed Vin signal, a sensed Vout signal and a sensed Iout signal. A battery current regulator (BCR) is coupled to receive the sensed Iout signal and an Iout reference, and outputs a first duty cycle control signal. An input voltage regulator (IVR) receives the sensed Vin signal and a Vin reference. The IVR provides a second duty cycle control signal. A processor receives the sensed Iout signal and utilizes a Maximum Power Point Tracking (MPPT) algorithm, and provides the Vin reference to the IVR. A selection block forwards one of the first and second duty cycle control signals as a duty cycle control signal to the power converter. Dynamic switching between the first and second duty cycle control signals maximizes the power delivered to the battery.

Elmes, John↗
NASA NTRS1972

Improved silver-zinc battery-terminal seals

Development of battery terminal seal for sealing electrolyte for periods of three to five years is discussed. Operating conditions of battery are defined. Components of electrolyte seal and method of production are reported. Schematic diagrams of device are included.

Snider, W. E.↗
NASA NTRS2004

Lunar and Planetary Science XXXV: Asteroids, Meteors, Comets

Session 13 of the Thirty-Fifth Lunar and Planetary Science Conference that took place on Tuesday, March 16, 2004. This session includes reports on asteroids, meteors, and comets. The attached document is a listing of all reports included in this session. The full text documents for each report is available in the Related Records section.

Lunar and Planetary Institute↗
NASA NTRS1983

Integrated Flywheel Technology 1983

Topics of discussion included: technology assessment of the integrated flywheel systems, potential of system concepts, identification of critical areas needing development and, to scope and define an appropriate program for coordinated activity.

Claude R Keekler↗
NASA NTRS2026

Isotopic Signature of Organic Molecules from Beyond the Solar System: An Enriched Methane D/H Ratio in the Interstellar Object 3I/ATLAS

Interstellar objects are interlopers from other planetary systems, and their volatile compositions provide a glimpse into planet formation around their host star. We present near-infrared spectra of the coma of interstellar object 3I/ATLAS measured with the James Webb Space Telescope. Our results demonstrate an unexpectedly high D/H = (3.31 ± 0.34)% for methane and represent an exceedingly rare detection of deuterated organic molecules in an interstellar object. This D/H ratio is a factor of 14 ± 2 higher than that measured in comet 67P/Churyumov-Gerasimenko by the Rosetta spacecraft, the only other comet for which CH3D has been detected, yet the ratio of deuteration in methane compared with water is consistent for both comets within 1.2σ. The D/H ratio in methane is observationally unconstrained in extrasolar sources to date, but the enriched ratio in 3I/ATLAS is most similar to those measured in other organic molecules toward primitive environments. The high D/H ratios of water and methane in 3I/ATLAS are a natural consequence of formation in a high D/H elemental ratio environment as a result of locally cold conditions in the protoplanetary disk and prior interstellar cloud. Thus, 3I/ATLAS formed in an environment very different from that in which our Sun and planets originated.

Interstellar Object 3I/ATLAS↗
NASA NTRSDate not supplied

Artemis CubeSats Help Advance Exploration of the Moon, Mars, and Beyond

On April 1, NASA launched the Artemis II mission – the first crewed mission of the Artemis campaign. The nine-day lunar flyby launched on the agency’s SLS (Space Launch System) rocket and had four astronauts test the Orion spacecraft in high Earth orbit and in deep space. Four 12U CubeSats also launched on the mission, housed within the SLS’s Orion stage adapter (OSA). The spacecraft were deployed approximately five-and-a-half hours into the flight, following Orion separation and departure from SLS, as the SLS interim cryogenic propulsion stage (ICPS) and the attached OSA were in a high Earth orbit on an atmospheric disposal trajectory. All four CubeSats were successfully deployed from the launch vehicle. Deployment statuses of the spacecraft, along with updates about the SLS rocket and Artemis missions, are reported in this paper. The paper will also discuss opportunities for CubeSat payloads on future Artemis missions.

David Hitt↗
NASA NTRS2020

The Slow Demise of the Long-Lived Sn 2005ip

The Type IIn supernova (SN IIn) 2005ip is one of the most well-studied and long-lasting examples of an SN interacting with its circumstellar environment. The optical light curve plateaued at a nearly constant level for more than five years, suggesting ongoing shock interaction with an extended and clumpy circumstellar medium (CSM). Here, we present continued observations of the SN from ∼1000 to 5000 d post-explosion at all wavelengths, including X-ray, ultraviolet, near-infrared (NIR), and mid-infrared. The UV spectra probe the pre-explosion mass loss and show evidence for CNO processing. From the bolometric light curve, we find that the total radiated energy is in excess of 10 50 erg, the progenitor star’s pre-explosion mass-loss rate was >~ 1 × 10 −2 Mꙩ yr −1 , and the total mass lost shortly before explosion was >~1Mꙩ, though the mass lost could have been considerably larger depending on the efficiency for the conversion of kinetic energy to radiation. The ultraviolet through NIR spectrum is characterized by two high-density components, one with narrow high-ionization lines, and one with broader low-ionization H I, He I, [OI], Mg II, and Fe II lines. The rich Fe II spectrum is strongly affected by Lyα fluorescence, consistent with spectral modelling. Both the Balmer and He I lines indicate a decreasing CSM density during the late interaction period. We find similarities to SN 1988Z, which shows a comparable change in spectrum at around the same time during its very slow decline. These results suggest that, at long last, the shock interaction in SN 2005ip may finally be on the decline.

stars↗
NASA NTRS1992

Spacecraft thermal control coatings: Comparison between flight results obtained on LDEF and MIR

The COMES experiment was installed outside of the MIR space station during an extravehicular activity. The experiment was exposed to vacuum, atomic oxygen, and ultraviolet radiation (UV) for 1.1 years. Due to a lack of knowledge about the spacecrafts actual attitude, there is a large uncertainty in the atomic oxygen fluence and the UV dose that was experienced by COMES. Additionally, contaminants of many different origins were observed on the COMES samples.

Jean-Claude Guillaumon↗
NASA NTRS1993

Failure Modes of Reduced-Order Orbit Determination Filters and Their Remedies

Ways in which failure can occur in reduced-order, orbit determination filter, error covariance calculations are discussed. In the context of this article, reduced-order filters denote nonoptimal filters which include fixed levels of uncertainty in some parameters of the measurement models or in the spacecraft dynamical model which are not explicitly estimated in the filter equations. Failure is defined as an increase in the orbit determination covariance with the addition of data or as an unreasonable growth in the covariance with time, i.e., nonasymptotic behavior of the covariance. Some simple, known cases of failure are discussed along with their traditional remedies. In addition, more modern remedies are discussed which are currently under development at the Jet Propulsion Laboratory. The article first describes the known problems of reduced-order filters when they are employed for orbit determination, and their traditional remedies. Then, having defined these, the relevancy and desirability of the more modern remedies are made apparent.

D J Scheeres↗
NASA NTRSDate not supplied

Artemis CubeSats Help Advance Exploration of the Moon, Mars, and Beyond

On April 1, NASA launched the Artemis II mission – the first crewed mission of the Artemis campaign. The nine-day lunar flyby launched on the agency’s SLS (Space Launch System) rocket and had four astronauts test the Orion spacecraft in high Earth orbit and in deep space. Four 12U CubeSats also launched on the mission, housed within the SLS’s Orion stage adapter (OSA). The spacecraft were deployed approximately five-and-a-half hours into the flight, following Orion separation and departure from SLS, as the SLS interim cryogenic propulsion stage (ICPS) and the attached OSA were in a high Earth orbit on an atmospheric disposal trajectory. All four CubeSats were successfully deployed from the launch vehicle. Deployment statuses of the spacecraft, along with updates about the SLS rocket and Artemis missions, are reported in this paper. The paper will also discuss opportunities for CubeSat payloads on future Artemis missions.

Russell Lane↗
NASA NTRS1970

Space Transportation System Technology Symposium. Volume 2 - Dynamics and Aeroelasticity

The Space Shuttle, being an hybrid – an airplane and a launch vehicle – represents the greatest challenge that the dynamicist and the aeroelastician have faced. Some specific problem areas related to the Space Shuttle are listed on figure 1. Dynamics and aeroelasticity envelop many disciplines, including aerodynamics, vibration, random processes, structures, fluid flow, mechanics, etc., but, of more importance, they involve the interaction and coupling of many of these various disciplines. Fundamentally, we are concerned with structural integrity and safe flight, i.e., trying to ensure that the vehicle will remain structurally intact as well as function properly in the presence of the many faceted dynamic environment. A new area which may have an impact on our task is the effect of the high temperature environment. In the past, we have been able to successfully decouple the temperature effects from our problem formulation. For the Space Shuttle, this problem must be closely reexamined. As has been pointed out in the opening remarks of the Conference, the Dynamics and Aeroelasticity Technology Group comprises one of several technology groups which are attempting to provide the necessary research to support a successful and safe vehicle. The group has members from most of the NASA Centers as well as from the Air Force groups. We meet periodically to review ongoing work, search for new problem areas; and we are constantly updating and revising our program. The group is organized into three panels as shown on figure 2: a panel on Dynamic Loads and Response, one on Aeroelasticity, and one on Flight Dynamics and Environment. The Conference papers accordingly have been grouped in these same three areas, with each Panel Chairman acting as moderator for his particular session.

Harry L Runyan↗
NASA NTRS1979

Dynamic analysis of a photovoltaic power system with battery storage capability

A photovolataic power system with a battery storage capability is analyzed. A dual battery current control concept is proposed, which enables the battery to either supply or accept power depending upon system environment and load conditions. A simulation of the power system, including the battery current control, is developed and evaluated. The evaulation demonstrate the visbility of the battery control concept of switch the battery from a charge to discharge mode and back as required by load and environmental conditions. An acceptable system operation is demonstrated over the entire insolation range. Additionally, system sensitivity, bandwidth, and damping characteristics of the battery control are shown to be acceptable for a projected hardware implementation.

Merrill, W. C.↗
NASA NTRS2003

Sixth International Conference on Mars

This publication contains the extended abstracts that were accepted for presentation at the 6th International Conference on Mars, held in Pasadena, CA July 20-25, 2003. The file contains the preface, table of contents, program, abstracts, and indexes. The extended abstracts review and debate some of the key questions and controversies that have matured during the flood of MGS and Odyssey data. The papers are presented in PDF format and are indexed by abstract author, and program author.

Steven Mackwell↗
NASA NTRS2026

Petermann Glacier on the Brink: Progress, Challenges and Insights

Petermann Glacier, the largest marine-terminating glacier in northern Greenland based on catchment area and ice discharge, plays a key role in regulating ice discharge from the Greenland Ice Sheet into the Arctic Ocean. With an upstream catchment connected to the ice sheet interior via a deep subglacial canyon, its future stability has major implications for sea level rise. In this review, we synthesize recent advances in understanding Petermann’s dynamics across three critical interfaces: the ice–ocean, ice–atmosphere, and ice–bed boundaries. At the surface, observations show that reanalysis products underestimate air temperatures and melt, while regional climate models diverge significantly in their estimates of surface mass balance, underscoring the need for improved in situ data and models. At the ocean boundary, enhanced basal melting driven by both subglacial runoff and Atlantic water intrusions is identified as the dominant driver of recent mass loss of Petermann Glacier, with continued warming posing a serious threat to the stability of the floating tongue. At the bed, new geophysical synthesis reveals complex geology, likely spatial variability in geothermal heat flux, and the influence of the megacanyon on seasonal hydrology and velocity fluctuations. Petermann’s mass balance has been negative in recent decades without corresponding flow acceleration. However, the glacier has undergone significant calving events, and the current rifting that began in September 2025 highlights its vulnerability. This upcoming calving event underscores the timeliness of this review, as it will put Petermann Glacier’s terminus at its most retreated position since records began in 1923. The anticipated retreat of the ice tongue also reduces buttressing and brings the terminus closer to the grounding zone, and modeling studies suggest that calving within 12 km of the grounding zone could potentially trigger dynamic retreat, accelerating ice discharge, and a doubling of flow speeds. We conclude that improved observations, sustained monitoring of oceanographic and atmospheric properties, and high-resolution modeling are critical to constraining projections of Petermann Glacier’s future and its role in the stability of the Greenland Ice Sheet.

Dominik Fahrner↗