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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 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1963

LATERAL-RANGE AND HYPERSONIC LIFT-DRAG-RATIO REQUIREMENTS FOR EFFICIENT FERRY SERVICE FROM A NEAR-EARTH MANNED SPACE STATION

The operation of any long-term manned space station will require some type of ferry vehicle to transport men and equipment to and from the station with regularity and reliability. Such a vehicle, designed for entry at near-orbital speeds, could also be useful in the return from any deeper space mission if either an earth-orbit rendezvous terminal maneuver or a maneuver combining atmospheric braking and a near-earth parking orbit is used. This study was undertaken to determine the class of vehicle which could be most efficiently used as a ferry vehicle between a near-earth space station and the earth. One measure of this efficiency is the ability of the vehicle to reach pre-chosen landing sites with some prescribed frequency. In considering this frequency of return it is necessary to consider not only the normal mode of operation in which only infrequent returns are scheduled at desirable times, but also operation under various degrees of emergency, which dictate quick or even immediate return to earth. In extreme emergencies, when immediate return to earth is necessary, choice of landing site becomes impractical. In most cases, however, although it might be required to abandon the station quickly, the ferry vehicle could remain in orbit for some time before initiating reentry in order to land at a prechosen site. The allowable delay time in orbit would be determined primarily by the capabilities of the ferry life-support system. This paper will examine the geometry of the ferry ranging problem, that is, the lateral ranges required to reach chosen landing sites from various near-earth orbits, and will investigate and compare several means of achieving these ranges. The particular case considered is that of returning from a space station which is in a circular orbit at an altitude of 200 statute miles, but the results obtained are not sensitive to orbit altitude for orbits within a few hundred miles of the surface. From this orbit, the vehicle will retro and reenter at very close to satellite velocity. The downrange problem can be handled by proper timing of the retrofiring , and the desired lateral range can be achieved by aerodynamics, space propulsion to change orbit plane, atmospheric propulsion, or combinations of these methods. The relative cost in terms of weight of using these different methods to achieve lateral range will be discussed.

Hypersonic vehicle↗
NASA NTRS2012

Spacecraft Conceptual Design for Returning Entire Near-Earth Asteroids

In situ resource utilization (ISRU) in general, and asteroid mining in particular are ideas that have been around for a long time, and for good reason. It is clear that ultimately human exploration beyond low-Earth orbit will have to utilize the material resources available in space. Historically, the lack of sufficiently capable in-space transportation has been one of the key impediments to the harvesting of near-Earth asteroid resources. With the advent of high-power (or order 40 kW) solar electric propulsion systems, that impediment is being removed. High-power solar electric propulsion (SEP) would be enabling for the exploitation of asteroid resources. The design of a 40-kW end-of-life SEP system is presented that could rendezvous with, capture, and subsequently transport a 1,000-metric-ton near-Earth asteroid back to cislunar space. The conceptual spacecraft design was developed by the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) team at the Glenn Research Center in collaboration with the Keck Institute for Space Studies (KISS) team assembled to investigate the feasibility of an asteroid retrieval mission. Returning such an object to cislunar space would enable astronaut crews to inspect, sample, dissect, and ultimately determine how to extract the desired materials from the asteroid. This process could jump-start the entire ISRU industry.

asteroid retrieval↗
NASA NTRS2004

Sample Return Science by Hayabusa Near-Earth Asteroid Mission

Assigning the material species to each asteroid spectral type and finding out the corresponding meteorite category is crucial to make the global material map in the whole asteroid belt and to understand the evolution of the asteroid belt. Recent direct observations by spacecrafts are revealing new intriguing aspects of asteroids which cannot be obtained solely from ground-based observations or meteorite studies. However identification of the real material species constituting asteroids and their corresponding meteorite analogs are still ambiguous. Space weathering makes difficult to identify the true material, and there is still a great gap between the remote sensing data on the global surface and the local microscopic data from meteorites. Sample return from asteroids are inevitable to solve these problems. For this purpose sample return missions to asteroids belonging to various spectral classes are required. The HAYABUSA spacecraft (prelaunch name is MUSESC) launched last year is the first attempt on this concept. This report presents outline of the mission with special stress on its science.

Fujiwara, A.↗
NASA NTRS1981

The 50 AMP-hour nickel cadmium battery manual

The battery is designed with a minimum battery to cell weight ratio consistent with adequate containment for operating conditions and dynamic environments and minimized weight. The battery is fully qualified and the environments to which it was successfully subjected were selected by NASA Goddard to cover a wide range of probable uses. The battery is suitable for either near-Earth geosynchronous missions, is compatible with passive or active thermal control systems and may be electrically controlled by a variety of changing routines. The initial application of the 50 A.H. Battery is a near-Earth mission aboard the LANDSAT D Satellite.

Webb, D. A.↗
NASA NTRS1986

Satellite debris - Recent measurements

More frequent reports concerning orbital debris damage to spacecraft have prompted the design, development and testing of equipment and techniques for the observation of moving objects by passive optical means. A consolidation is presently made of hundreds of hours of space debris observation, quantifying the numbers of small bodies in space relative to the actively watched artificial satellite population and estimating the numbers of detectable objects from near-earth orbit to geostationary orbit distances. The debris reported constitutes 11 times the tracked population in near-earth orbit and between 25 and 50 percent of the deep space population.

Taff, L. G.↗
NASA NTRS2024

The dynamical origins of the dark comets and a proposed evolutionary track

So-called ‘dark comets’ are small, morphologically inactive near-Earth objects (NEOs) that exhibit nongravitational accelerations inconsistent with radiative effects. These objects exhibit short rotational periods (minutes to hours), where measured. We find that the strengths required to prevent catastrophic disintegration are consistent with those measured in cometary nuclei and expected in rubble pile objects. We hypothesize that these dark comets are the end result of a rotational fragmentation cascade, which is consistent with their measured physical properties. We calculate the predicted size-frequency distribution for objects evolving under this model. Using dynamical simulations, we further demonstrate that the majority of these bodies originated from the 𝜈6 resonance, implying the existence of volatiles in the current inner main belt. Moreover, one of the dark comets, (523599) 2003 RM, likely originated from the outer main belt, although a JFC origin is also plausible. These results provide strong evidence that volatiles from a reservoir in the inner main belt are present in the near-Earth environment.

Aster G Taylor↗
NASA NTRS1963

LOOK AT THE REENTRY PROBLEM

Reentry guidance and control in near-earth orbits and near escape velocity as well as in deep space and at velocities in excess of escape velocity

DEEP SPACE↗
NASA NTRS1960

Problems in Atmosphere Entry from Parabolic Orbits

Up to the present time we have been concerned with sending small instrumented probes into interplanetary space and larger bodies into near-earth satellite orbits. Only recently we have begun to recover intact some of these orbiting bodies and soon we will carry on this program to the recovery of manned satellites. In the not-too-distant future we will be concerned with transit to and from the moon and the planets. It is with the problems of entry into our atmosphere of these higher speed vehicles that this paper will be concerned.

Allen, H. Julian↗
NASA NTRS1974

Future NASA plans for the exploration of the terrestrial and planetary atmospheres

A brief outline of NASA's space exploration plans for the 1970s is given. Research of the upper atmosphere and near-earth space will slack off in comparison with that which was done in the past, although now missions with very specific tasks will be launched, instead of those intended to get a general picture of these regions. Space Shuttle and Spacelab will open up the possibility of using the ionosphere as a huge plasma laboratory without walls. Exploration of other planets will continue with the Mars Lander and Viking Lander, the Pioneer-Venus program, and flybys of Jupiter and Saturn.

Bauer, S.↗
NASA NTRS1960

A Two-Impulse Plan for Performing Rendezvous on a Once-A-Day Basis

An investigation of a two-impulse plan for performing rendezvous on a once-a-day basis with a near-earth satellite station indicates that launch into rendezvous from slightly less than maximum satellite latitude is an unusually favorable circumstance in that no appreciable expense in mass ratio is incurred. In addition, it was found for the two-impulse maneuver employed in this study that the optimum angular travel of the ferry vehicle to rendezvous was considerably less than the 1800 transfer which is optimum for the two-impulse in-plane launch.

Bird, John D.↗
NASA NTRS1961

Determination of the Required Number of Randomly Spaced Communication Satellites

An investigation has been made f o r determining the minimum number of passive satellites i n near-earth orbits required t o provide given percentages of communication time between two selected ground stations. The study is limited to the geometrical and probability aspects of the problem. An application of the analysis i s made f o r an assumed transatlantic communication system. The satellites are considered t o be i n circular, randomly spaced orbits with fixed inclination and altitude considered range from 1,000 t o 3,000 statute miles.

Bennett, Floyd V.↗
NASA NTRS1961

Flight Performance Handbook for Orbital Operations: Orbital Mechanics and Astrodynamics Formulae, Theorems, Techniques, and Applications

This handbook provides parametric data useful both to the space vehicle designer and mission analyst. It provides numerical and analytical relationships between missions and gross vehicle characteristics as a function of performance parameters. The effects of missile constraints and gross guidance limitations plus operational constraints such as launch site location, tracking net location, orbit visibility and mission on trajectory and orbit design parameters are exhibited. The influence of state-of- the-art applications of solar power as compared to future applications of nuclear power on orbit design parameters, such as eclipse time, are among the parameters included in the study. The principal aim, however, is in providing the analyst with useful parametric design information to cover the general area of earth satellite missions in the region of near-earth to cislunar space and beyond and from injection to atmospheric entry and controlled descent. The chapters are organized around the central idea of orbital operations in the 1961-1969 era with emphasis on parametric flight mechanics studies for ascent phase and parking orbits, transfer maneuvers, rendezvous maneuver, operational orbit considerations, and operational orbit control. The results are based almost entirely on the principles of flight and celestial mechanics. Numerous practical examples have been worked out in detail. This is especially important where it has been difficult or impossible to represent all possible variations of the parameters. The handbook contains analytical formulae and sufficient textual material to permit their proper use. The analytic methods consist of both exact and rapid, approximate methods. Scores of tables, working graphs and illustrations amplify the mathematical models which, together with important facts and data, cover the engineering and scientific applications of orbital mechanics. Each of the five major chapters are arranged to provide a rapid review of an entire astrodynamic subject. By the use of compact graphical and tabular presentation the full scope of the material is made available in an easy-to-use style. Throughout the volume the analyst is shown, by means of suitable introductions, notes, authoritative examples, and cross-references the vital interrelation of the various orbital mechanics topics in the general field of earth satellites and satellite rendezvous. The handbook is designed to give the analyst rapid, reliable access to the mathematics of orbital mechanics needed for virtually any working requirements.

Ambrosio, Alphonso↗
NASA NTRS2026

Space Mission Options for Reconnaissance and Mitigation of Asteroid 2024 YR4

Near-Earth asteroid 2024 YR 4 was discovered on 2024-12-27 and its probability of Earth impact in December 2032 peaked at about 3% on 2025-02-18. Additional observations ruled out Earth impact by 2025-02-23. However, the probability of lunar impact in December 2032 then rose, reaching about 4% by the end of the apparition in May 2025. James Webb Space Telescope (JWST) observations on 2025-03-26 estimated the asteroid's diameter at 60 +/- 7 m. Studies of 2024 YR 4 's potential lunar impact effects suggest lunar ejecta could increase micrometeoroid debris flux in low Earth orbit up to 1000 times above background levels over just a few days, possibly threatening astronauts and spacecraft. In this work, we present options for space missions to 2024 YR 4 that could be utilized if lunar impact is confirmed. We cover flyby & rendezvous reconnaissance, deflection, and robust disruption of the asteroid. We examine both rapid-response and delayed launch options through 2032. We evaluate chemical and solar electric propulsion, various launch vehicles, optimized deep space maneuvers, and gravity assists. Re-tasking extant spacecraft and using built spacecraft not yet launched are also considered. The best reconnaissance mission options launch in late 2028, leaving only approximately three years for development at the time of this writing in August 2025. Deflection missions were assessed and appear impractical. However, kinetic robust disruption missions are available with launches between April 2030 and April 2032. Nuclear robust disruption missions are also available with launches between late 2029 and late 2031. Finally, even if lunar impact is ruled out there is significant potential utility in deploying a reconnaissance mission to characterize the asteroid.

Asteroid Disruption↗
NASA NTRS2026

Electron Velocity Moments in the Solar Wind. I. Calibration of the Wind 3DP EESA Low Detector

Calibrated measurements of electron velocity distribution functions (VDFs) are necessary to characterize fluid and kinetic processes in weakly collisional and nearly collisionless plasmas such as the solar wind. Therefore, we analyzed 3,996,051 electron VDFs observed by the Wind 3DP thermal electron detector near 1 astronomical unit (au) between January 1, 2005 and November 25, 2017. The data were calibrated for each electron VDF to produce accurate velocity moments in the solar wind. This is the first full solar cycle coverage electron velocity moment dataset in the near-Earth solar wind. Herein (Paper I) we discuss the calibration process/algorithms and the velocity moment constraints, uncertainties, and resulting public dataset. In the second paper (Paper II), we statistically analyze the electron velocity moment dataset.

plasmas↗