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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 649 records · Page 36

The NASA In-Space Propulsion Technology Project's Current Products and Future Directions

Since its inception in 2001, the objective of the In-Space Propulsion Technology (ISPT) project has been developing and delivering in-space propulsion technologies that enable or enhance NASA robotic science missions. These in-space propulsion technologies are applicable, and potentially enabling for future NASA flagship and sample return missions currently under consideration, as well as having broad applicability to future Discovery and New Frontiers mission solicitations. This paper provides status of the technology development, applicability, and availability of in-space propulsion technologies that recently completed, or will be completing within the next year, their technology development and are ready for infusion into missions. The paper also describes the ISPT project s future focus on propulsion for sample return missions. The ISPT technologies completing their development are: 1) the high-temperature Advanced Material Bipropellant Rocket (AMBR) engine providing higher performance for lower cost; 2) NASA s Evolutionary Xenon Thruster (NEXT) ion propulsion system, a 0.6-7 kW throttle-able gridded ion system; and 3) aerocapture technologies which include thermal protection system (TPS) materials and structures, guidance, navigation, and control (GN&C) models of blunt-body rigid aeroshells; and atmospheric and aerothermal effect models. The future technology development areas for ISPT are: 1) Planetary Ascent Vehicles (PAV); 2) multi-mission technologies for Earth Entry Vehicles (MMEEV) needed for sample return missions from many different destinations; 3) propulsion for Earth Return Vehicles (ERV) and transfer stages, and electric propulsion for sample return and low cost missions; 4) advanced propulsion technologies for sample return; and 5) Systems/Mission Analysis focused on sample return propulsion.

Anderson, David J.↗

Viscous-shock-layer solutions with radiation and ablation injection for Jovian entry

This paper presents results that describe the flow field and surface response conditions for a planetary probe entering the atmosphere of Jupiter. The results are obtained with a viscous-shock-layer analysis which includes mass injection, radiative transfer, diffusion, and viscous effects. Radiative transfer is calculated with an existing nongray radiation model that accounts for molecular band, atomic line, and continuum transitions. Particular emphasis is given to the effect of mass injection on the stagnation and downstream flow. Results for both specified and coupled mass injection are obtained for a carbon heat shield.

Moss, J. N.↗

Design comparison of lunar return configurations

Parabolic manned re-entry design comparisons are made between two classes of slender and blunt configurations capable of conventional horizontal and vertical earth landings. Aerodynamic modulation using flaps and control augmentation requirements are discussed in terms of their effect upon re-entry trajectories and landing footprints. Within the environment defined by the re-entry trajectories, the convective and radiative modes of heat transfer are compared, their differences discussed, and the problems associated with the configurations for planetary return missions indicated. Thermal protection systems are discussed and the factors influencing the selection of a given system for the re-entry environment are indicated. Comparison between reflective and absorptive systems are made and the merits of each for a given flight time indicated. A thermo-structural analysis is presented which shows the trade-oft between structural operating temperature and heat protection system thickness requirements. Total heat shield and structural weights are compared for the landing footprints presented and their variation with range shown. Finally, the areas of uncertainty in the aero-thermo structural design analysis are indicated for each class of configuration studied, and the weight differences between conventional horizontal landing and vertical descent configurations are given.

Parabolic flight↗

Geophysical Observations of the 2023 September 24 OSIRIS-REx Sample Return Capsule Reentry

Sample return capsules (SRCs) entering Earth's atmosphere at hypervelocity from interplanetary space are a valuable resource for studying meteor phenomena. The 2023 September 24 arrival of the Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer SRC provided an unprecedented chance for geophysical observations of a well-characterized source with known parameters, including timing and trajectory. A collaborative effort involving researchers from 16 institutions executed a carefully planned geophysical observational campaign at strategically chosen locations, deploying over 400 ground-based sensors encompassing infrasound, seismic, distributed acoustic sensing, and Global Positioning System technologies. Additionally, balloons equipped with infrasound sensors were launched to capture signals at higher altitudes. This campaign (the largest of its kind so far) yielded a wealth of invaluable data anticipated to fuel scientific inquiry for years to come. The success of the observational campaign is evidenced by the near-universal detection of signals across instruments, both proximal and distal. This paper presents a comprehensive overview of the collective scientific effort, field deployment, and preliminary findings. The early findings have the potential to inform future space missions and terrestrial campaigns, contributing to our understanding of meteoroid interactions with planetary atmospheres. Furthermore, the data set collected during this campaign will improve entry and propagation models and augment the study of atmospheric dynamics and shock phenomena generated by meteoroids and similar sources.

46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND ↗

Listening for the Landing: Seismic Detections of Perseverance's Arrival at Mars With InSight

The entry, descent, and landing (EDL) sequence of NASA's Mars 2020 Perseverance Rover will act as a seismic source of known temporal and spatial localization. We evaluate whether the signals produced by this event will be detectable by the InSight lander (3,452 km away), comparing expected signal amplitudes to noise levels at the instrument. Modeling is undertaken to predict the propagation of the acoustic signal (purely in the atmosphere), the seismoacoustic signal (atmosphere-to-ground coupled), and the elastodynamic seismic signal (in the ground only). Our results suggest that the acoustic and seismoacoustic signals, produced by the atmospheric shock wave from the EDL, are unlikely to be detectable due to the pattern of winds in the martian atmosphere and the weak air-to-ground coupling, respectively. However, the elastodynamic seismic signal produced by the impact of the spacecraft's cruise balance masses on the surface may be detected by InSight. The upper and lower bounds on predicted ground velocity at InSight are 2.0 × 10 -14 and 1.3 × 10 -10 m s -1 . The upper value is above the noise floor at the time of landing 40% of the time on average. The large range of possible values reflects uncertainties in the current understanding of impact-generated seismic waves and their subsequent propagation and attenuation through Mars. Uncertainty in the detectability also stems from the indeterminate instrument noise level at the time of this future event. A positive detection would be of enormous value in constraining the seismic properties of Mars, and in improving our understanding of impact-generated seismic waves.

58 GEOSCIENCES↗

Maturation of the Asteroid Threat Assessment Project

As described at IPPW 12 [1], NASA initiated a new research activity focused on Planetary Defense (PD) on October 1, 2014. The overarching function of the Asteroid Threat Assessment Project (ATAP) is to provide capabilities to assess impact damage of any Near-Earth Object (NEO) that could inflict on the Earth. The activity includes four interrelated efforts: Initial Conditions (at the atmospheric entry interface); Entry Modeling (energy deposition in the atmosphere); Hazards (on the surface including winds, over pressures, thermal exposures, craters, tsunami and earthquakes) and Risk (physics-based). This paper outlines progress by ATAP and highlights achievements that are complimentary to activities of interest to the International Planetary Probe community. The ATAPs work is sponsored by NASAs Planetary Defense Coordination Office (PDCO), a part of the agency's Science Mission Directorate [1] Arnold, J. O., et. al., Overview of a New NASA Activity Focused on Planetary Defense, IPPW 12 Cologne Germany, June 15-19. 2015.

Entry and Breakup↗

Study of entry and landing probes for exploration of Titan

Saturn's largest moon, Titan, is a totally unique planetary body which is certain to yield exciting new phenomena. Current information is lacking in detail to distinguish between a thin methane rich atmosphere and a thick nitrogen rich atmosphere. Therefore, both the thin and thick atmospheric models were used for the study of various Titan probe classes described in this report. The technical requirements, conceptual design, science return, schedule, cost and mission implications of three probe classes that could be used for exploration of Titan are defined. The three probe classes were based on a wide range of exploration mission possibilities.

Source record↗

Aerocapture - A system design for planetary exploration

The paper presents the results of a study that developed conceptual designs of an atmospheric entry system with moderate to high L/D ratios to establish the concepts of aerocapture into low circular Mars orbits from hyperbolic flyby trajectories. The payloads considered in this study were those currently conceived for the Mars Sample Return (MSR) mission including single mission (SM) and multi-mission (MM) modes. The design concepts developed are also applicable (with small modification) for establishment of closed orbits about Venus and Saturn. The MSR mission payload requires an orbiter, lander, ascent vehicle, and rover, with a total mass of approximately 4000 kg. The emphasis during the study was placed on development of concepts for aerodynamic configuration, the aeroshell design, and a guidance, navigation, and control subsystem.

Cruz, M. I.↗

Maneuver Analysis and Targeting Strategy for the Stardust Re-Entry Capsule

Stardust employed biased maneuvers to limit turns and minimize execution errors. Biased maneuvers also addressed planetary protection and safety issues. Stardust utilized a fixed-direction burn for the final maneuver to match the prevailing attitude so no turns were needed. Performance of the final burn was calibrated in flight.

targeting↗

Comets, meteorites and atmospheres

The relatively low value of Xe/Kr in the atmospheres of Earth and Mars seems to rule out meteorites as the major carriers of noble gases to the inner planets. Laboratory experiments on the trapping of gases in ice forming at low temperatures suggest that comets may be a better choice. It is then possible to develop a model for the origin of inner planet atmospheres based on volatiles delivered by comets added to volatiles originally trapped in planetary rocks. The model will be tested by results from the Galileo Entry Probe.

NASA Discipline Exobiology↗

Earth Entry Requirements for Mars, Europa and Enceladus Sample Return Missions: A Thermal Protection System Perspective

This oral presentation will be given at the 13th International Planetary Probe Workshop on June 14th, 2016 and will cover the drivers for reliability and the challenges faced in selecting and designing the thermal protection system (TPS). In addition, an assessment is made on new emerging TPS related technologies that could help with designs to meet the planetary protection requirements to prevent backward (Earth) contamination by biohazardous samples.

Earth Entry↗

Engineering approximations for Jovian entry

A code has been written to describe the behavior of an ablating heat shield throughout the entire maneuver into a planetary atmosphere. The code includes a trajectory computation for a variable mass, a computation of the heating history and distribution over the probe, ablation effects, indepth material response, and shape change. The code draws the initial and final shapes of the heat shield and computes its initial and final mass. Results are compared with those of other investigators, and solutions are obtained for a silica heat shield entering three model atmospheres of Jupiter. The effects of varying half cone angle and entry angle are examined as well as shape change effects. The so-called 'cusping effect' in the stagnation region is examined.

Lasher, L. E.↗

High-accuracy Mars approach navigation with radio metric and optical data

The aerocapture of a space vehicle on hyperbolic approach to Mars results in tight navigation requirements at atmospheric entry. The purpose of this paper is to examine several different methods for approach navigation and to determine what accuracies are possible. The methods are broken into four groups as follows (1) navigation with only Deep Space Network (DSN) tracking of the approach vehicle, (2) navigation with the DSN plus ranging between the approach vehicle and spacecraft in orbit about Mars, (3) navigation with the DSN plus optical data involving the Martian moons, and (4) navigation with DSN range data and differenced range data involving the approach spacecraft and orbiters at Mars. If the current modeling errors that affect earth-based radio metric data, such as errors in tracking station locations, the Martian ephemeris, and differences in the quasar and planetary coordinate frames, are improved, then perhaps earth-based tracking could meet the entry error requirements imposed by aerocapture. If not, then the other three options of intervehicular range, optical data, or differenced range provide highly accurate entry knowledge at least twelve hours before entry.

Konopliv, Alex↗

An Approach to Simulation of Extreme Conditions for a Planetary Lander

A "Monte Carlo-like" design analysis tool is developed and applied to an aeromaneuvering Mars entry vehicle. This tool provides realistic but challenging design cases using many fewer cases than a full Monte Carlo analysis. The problem of random input variables that are provided a priori (as opposed to being drawn from a given distribution) is addressed and a solution is found that shows prospects for future improvement.

Queen, Eric M.↗

Next Generation Simulation Framework for Robotic and Human Space Missions

The Dartslab team at NASA's Jet Propulsion Laboratory (JPL) has a long history of developing physics-based simulations based on the Darts/Dshell simulation framework that have been used to simulate many planetary robotic missions, such as the Cassini spacecraft and the rovers that are currently driving on Mars. Recent collaboration efforts between the Dartslab team at JPL and the Mission Operations Directorate (MOD) at NASA Johnson Space Center (JSC) have led to significant enhancements to the Dartslab DSENDS (Dynamics Simulator for Entry, Descent and Surface landing) software framework. The new version of DSENDS is now being used for new planetary mission simulations at JPL. JSC is using DSENDS as the foundation for a suite of software known as COMPASS (Core Operations, Mission Planning, and Analysis Spacecraft Simulation) that is the basis for their new human space mission simulations and analysis. In this paper, we will describe the collaborative process with the JPL Dartslab and the JSC MOD team that resulted in the redesign and enhancement of the DSENDS software. We will outline the improvements in DSENDS that simplify creation of new high-fidelity robotic/spacecraft simulations. We will illustrate how DSENDS simulations are assembled and show results from several mission simulations.

Dartslab↗