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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 NTRSDate not supplied

Development of an Extended Reality (XR) Tool for Earth Science Visualization

In this presentation, we will discuss our work in adapting the NASA open source XR software, the Mixed Reality Exploration Toolkit (MRET), to an earth science domain. MRET is a NASA open source XR software for rapidly building extended reality (XR) environments for NASA domain problems, e.g., pulling in CAD models of thermal vac chamber and Roman Space Telescope to do fit checks. Primarily used for hardware integration & test, we have been adapting and extending MRET for science problems. Traditionally, scientists view and analyze the result of calculated or measured observables with static 1-D, 2-D or 3-D plots. It can be difficult to identify, track and understand the evolution of key features due to poor viewing angles and the nature of flat computer screens. Additionally, numerical models, such as the NASA GEOS climate model, are almost exclusively formulated and analyzed on Eulerian grids with points fixed in space and time. However, atmospheric phenomena such as convective clouds, hurricanes and wildfire smoke plumes move with the 3-D flow field, and it is often difficult and unnatural to understand these phenomena in an Eulerian reference frame as opposed to the Lagrangian reference frame in which nature operates. As part of an Earth Science Technology Office (ESTO) proposal, we have been adapting MRET to be a scientific exploration and analysis XR tool with integrated Lagrangian Dynamics (LD) for the Goddard Earth Observing System (GEOS) numerical weather prediction model. We believe this will help scientists identify, track, and understand the evolution of Earth Science phenomena. This presentation will discuss current results in our work in developing this XR tool for Earth Science.

Thomas Grubb↗
NASA NTRSDate not supplied

Massless Exploration – Humans as a Solar System Species

A vision for exploration of the solar system in an earth independent manner is presented taking into account key drivers, challenges and future technological advances. This work was in response to requirements set by the NASA Advanced Exploration Systems (AES) Office. Planetary targets, key assumptions and approaches to utilizing non-terrestrial resources are presented. The mission was divided into four sprints. The first sprint aims at a settlement on Earth’s moon. The second sprint aims at establishing a Lagrangian point station near the moon. The third sprint leads to the colonization of Mars and its moons. The fourth and final sprint investigated the exploration of Callisto, a moon of Jupiter. Bio-inspired approaches to technology and processes were considered to ensure that the in-space habitats are Earth like. The conclusion based on exploring the four sprints is that it is feasible to colonize the solar system without relying on earth but this relies on critical technology development and investments in emerging areas.

In-situ resource utilization↗
NASA NTRSDate not supplied

Massless Exploration: Humans as a Solar System Species

A vision for exploration of the solar system in an earth independent manner is presented taking into account key drivers, challenges and future technological advances. This work was in response to requirements set by the NASA Advanced Exploration Systems (AES) Office. Planetary targets, key assumptions and approaches to utilizing non-terrestrial resources are presented. The mission was divided into four sprints. The first sprint aims at a settlement on Earth’s moon. The second sprint aims at establishing a Lagrangian point station near the moon. The third sprint leads to the colonization of Mars and its moons. The fourth and final sprint investigated the exploration of Callisto, a moon of Jupiter.. Bio-inspired approaches to technology and processes were considered to ensure that the in-space habitats are Earth like. The conclusion based on exploring the four sprints is that it is feasible to colonize the solar system without relying on earth but this relies on critical technology development and investments in emerging areas.

In-situ resource utilization↗
NASA NTRS2021

Preconditioning of overcast-to-broken cloud transitions by riming in marine cold air outbreaks

Marine cold air outbreaks (CAOs) commonly form overcast cloud decks that transition into broken cloud fields downwind, dramatically altering the local radiation budget. In this study, we investigate the impact of frozen hydrometeors on these transitions. We focus on a CAO case in the NW Atlantic, the location of the multi-year flight campaign ACTIVATE (Aerosol Cloud meTeorology Interactions oVer the western ATlantic Experiment). We use MERRA-2 (Modern-Era Retrospective analysis for Research and Applications, version 2) reanalysis fields to drive large eddy simulations with mixed-phase two-moment microphysics in a Lagrangian framework. We find that transitions are triggered by substantial rain (rainwater paths >25 g m−2), and only simulations that allow for aerosol depletion result in sustained breakups, as observed. Using a range of diagnostic ice nucleating particle concentrations, Ninp, we find that increasing ice progressively accelerates transitions, thus abbreviating the overcast state. Ice particles affect the cloud-topped boundary layer evolution, primarily through riming-related processes prior to substantial rain, leading to (1) a reduction in cloud liquid water, (2) early consumption of cloud condensation nuclei, and (3) early and light precipitation cooling and moistening below cloud. We refer to these three effects collectively as “preconditioning by riming”. Greater boundary layer aerosol concentrations available as cloud condensation nuclei (CCN) delay the onset of substantial rain. However, cloud breakup and low CCN concentration final stages are found to be inevitable in this case, due, primarily, to liquid water path buildup. An ice-modulated cloud transition speed suggests the possibility of a negative cloud–climate feedback. To address prevailing uncertainties in the model representation of mixed-phase processes, the magnitude of ice formation and riming impacts and, thereby, the strength of an associated negative cloud–climate feedback process, requires further observational evaluation by targeting riming hot spots with in situ imaging probes that allow for both the characterization of ice particles and abundance of supercooled droplets.

Marine cold air outbreaks↗
NASA NTRS1963

A Variational Method for the Optimization of Interplanetary Round-Trip Trajectories

The indirect method of the calculus of variations is used to optimize interplanetary round-trip trajectories for the case of a single, central, attracting body. The method of solution makes use of certain partial derivative properties of the Lagrangian multipliers associated with the Mayer formulation of the variational problem. This property of the multipliers allows the construction of mathematical expressions for certain other partial derivatives that must vanish when an optimum round trip has been found. These expressions are developed for the cases of propulsion systems using (1) fixed thrust and specific impulse or (2) variable thrust and constant exhaust jet power. Two numerical examples demonstrate how the analytical results may be applied to the solution of round-trip problems including (1) actual three-dimensional planetary positions and (2) planetocentric maneuvers.

VARIATIONAL CALCULUS↗