The expanding horizons of air transport
Subsonic and supersonic transport aircraft design, discussing supercritical wing concept, fuel consumption reduction, composite aircraft structures, short haul transports, etc
Kayten, G. G.↗
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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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New horizons in astronomy.
Besides the study of astronomy itself, other topics included cover the geological and biological developments on earth and basic physics of matter, heat, and light. Optical and radio telescopes are discussed, as well as photographic and photoelectric means of detection. The immediate solar system is described by topics on the properties and atmospheres of the inner and outer planets, the sun's energy, sunspots, and the solar spectrum. Stars both on and off the main sequence are discussed in terms of distances, intrinsic properties, lifetimes and evolution. The Milky Way is compared to other galaxies in size, star population and structure, and the different galaxy shapes are pictured. Topics of most recent interest are covered by results of the lunar explorations, new concepts of Mars, and problems of space travel. Problems of modern astronomy include pulsars, neutron stars, and quasars.
Brandt, J. C.↗
Radiation measurements of the earth's horizon from the X-15
Explore the source record for details and available documents.
Jalink, A., Jr.↗
New horizons in chemical propulsion
After a review of the work of the late-Fifties on free radicals for propulsion, it is concluded that atomic hydrogen would provide a potentially large increase in specific impulse. Work conducted to find an approach for isolating atomic hydrogen is considered. Other possibilities for obtaining propellants of greatly increased capability might be connected with the technology for the generation of activated states of gases, metallic hydrogen, fuels obtained from other planets, and laser transfer of energy.
Cohen, W.↗
Determination of astronomical refraction near the horizon in different seasons of the year
The results are presented of astronomical refraction measurements for zenith distances of 80-90 degrees performed in different seasons with a two inch universal instrument. The differences between observed and calculated refraction were found to exhibit seasonal variations, and the results were compared with data of atmospheric aerologic soundings. The great departures in observed refraction from that calculated with the Pulkovo tables were ascribed to temperature gradient changes within the ground kilometer layer of atmosphere.
Vasilenko, N. A.↗
Planetary exploration - Earth's new horizon /Twelfth von Karman Lecture/
Planetary exploration is examined in terms of the interaction of technological growth with scientific progress and the intangibles associated with exploring the unknown. The field is limited to unmanned exploration of the planets and their satellites. A descriptive model of the endeavor, its activities and achievements in the past decade, a characterization of the current state of the art, and a look at some of the planetary mission opportunities for the next decade are presented. A case is made for the value to civilization of ongoing planetary exploration. The pioneering U.S. planetary explorers, Mars, Venus, and Jupiter, are discussed in the second part of the work. Launch velocity, navigation, the remote system, the earth base, and management technology are considered in the third part. Authorized near-term U.S. planetary projects and opportunities of the next decade are described in the last section.
Schurmeier, H. M.↗
Planetary exploration - Earth's new horizon /12th von Karman Lecture/
The article gives an account of the history of unmanned exploration of the planets of the solar system, including both earthbound exploration and exploration with spacecraft. Examples of images of the Martian surface are presented along with images obtained in Jupiter and Mercury flybys. Data are presented on the growth of US launch vehicle performance capability, navigation performance, and planetary data rate capability. Basic information regarding the nature of the scientific experiments aboard the Pioneer and Viking spacecraft is given. A case is put forward for the ongoing exploration of the planets as a worthwhile endeavor for man.
Schurmeier, H. M.↗
New horizons
The contribution of space exploration and space related research to the future of man and the accomplishments of the space program are assessed. Topics discussed include: the role of applications satellites in crop surveillance, land use surveys, weather forecasting, education, communications, and pollution monitoring; planetary studies which examine the origin and evolution of the solar system, including dynamic processes that bear directly on earth's environment; and fuel conservation and development of new energy sources.
Source record↗
New horizons for study of the cardiopulmonary and circulatory systems
The paper discusses the development of computer-controlled three-dimensional reconstruction techniques designed to determine the dynamic changes in the true shape and dimensions of the epi- and endocardial surfaces of the heart, along with variable time base (stop-action to real-time) displays of the transmural distribution of the coronary microcirculation and the three-dimensional anatomy of the macrovasculature in all regions of the body throughout individual cardiac and/or respiratory cycles. A technique for reconstructing a cross section of the heart from multiplanar videoroentgenograms is outlined. The capability of high spatial and high temporal resolution scanning videodensitometry makes possible measurement of the appearance, mean transit and clearance of roentgen opaque substances in three-dimensional space through the myocardium with a degree of simultaneous anatomic and temporal resolution not obtainable by current isotope techniques. The distribution of a variety of selected chemical elements or biologic materials within a body portion can also be determined.
Wood, E. H.↗
STS multimission modular spacecraft - A new horizon in social and industrial benefits
Economics and benefits of orbiting observatory Multi-mission Modular Spacecraft are discussed. The Space Shuttle can be used both to place these satellites in low-altitude workhorse orbits and to maintain their functioning in any of three ways - on-orbit service (by visiting the satellite with the Shuttle), Shuttle retrieval and ground refurbishment of the entire satellite, and replacement of a failed satellite with a new one. Individuals could receive information from these satellites either indirectly, by turning to a specialty television station, or directly, by calling up information on their television sets as needed. Such information, for example, might include reconnoitering interesting areas, following the weather, or locating migratory fish. Equipment and costs of the proposed Landsats and Seasats are discussed.
Cepollina, F. J.↗
The linear quadratic optimal control problem for infinite dimensional systems over an infinite horizon - Survey and examples
Available published results are surveyed for a special class of infinite-dimensional control systems whose evolution is characterized by a semigroup of operators of class C subscript zero. Emphasis is placed on an approach that clarifies the system-theoretic relationship among controllability, stabilizability, stability, and the existence of a solution to an associated operator equation of the Riccati type. Formulation of the optimal control problem is reviewed along with the asymptotic behavior of solutions to a general system of equations and several theorems concerning L2 stability. Examples are briefly discussed which involve second-order parabolic systems, first-order hyperbolic systems, and distributed boundary control.
Bensoussan, A.↗
Inversion of scattered radiance horizon profiles for gaseous concentrations and aerosol parameters
Techniques have been developed and used to invert limb scan measurements for vertical profiles of atmospheric state parameters. The parameters which can be found are concentrations of Rayleigh scatters, ozone, NO2, and aerosols, and aerosol physical properties including a Junge-size distribution parameter and real and imaginary parts of the index of refraction.
Malchow, H. L.↗
ATS-6 ascending - Near horizon measurements over water at 30 GHz
The return of the ATS-6 satellite to a western longitude during the fall of 1976 presented a unique opportunity to perform low-angle-of-elevation measurements at 30 GHz. For this purpose a receiver using a 1.5 m antenna was set up at Port Aransas, Texas, resulting in a propagation path entirely over water. The 30 GHz beacon was monitored daily for at least one hour from 8 September to 21 September 1976. During the time the elevation angle changed from 1.5 to 17.3 deg, the mean attenuation decreased from 20 to 2 dB and the standard deviation from over 6 dB to less than .2 dB. The deep fades at angles below 4 deg show significantly sharper nulls than peaks on a log scale. Spectra of the log amplitude fluctuations vary as the (-8/3) power of the spectral frequency in the limit. A flattening is noticeable at the low frequencies. A precipitation even at 8.5 deg elevation produced a 16 dB fade and significantly increased the variance.
Vogel, W. J.↗
ATS-6 ascending: Near horizon measurements over water at 30 GHz
The return of the ATS 6 satellite to a western longitude during the fall of 1976 presented a unique opportunity to perform low angle of elevation measurements at 30 GHz. For this purpose a receiver using a 1.5 m antenna was set up at Port Aransas, Texas, resulting in a propagation path entirely over water. The 30 GHz beacon was monitored daily for at least one hour from 8 September 1976 to 21 September 1976. During the time the elevation angle changed from 1.5 deg to 17.3 deg, the mean attenuation decreased from 20 dB to 2 dB and the standard deviation from over 6 dB to less than .2 dB. The deep fades at angles below 4 deg show significantly sharper nulls than peaks on a log scale. Spectra of the log amplitude fluctuations vary as the (-8/3) power of the spectral frequency in the limit. A flattening is noticeable at the low frequencies. A precipitation event at 8.5 deg elevation produced a 16 dB fade and significantly increased the variance.
Vogel, W. J.↗
Just over the horizon in space
The article surveys some of the concepts introduced and examined by a New Concepts Symposium convened by the NASA Advisory Council recently. Results are reported from the symposium's eight working groups: astrophysics, climate, communications and navigation, energy, large structures, planetary exploration, propulsion and transportation, and telefactors.
Bekey, I.↗
Limitless Horizons. Careers in Aerospace
A manual is presented for use by counselors in career guidance programs. Pertinent information is provided on choices open in aerospace sciences, engineering, and technology. Accredited institutions awarding degrees in pertinent areas are listed as well as additional sources of aerospace career information. NASA's role and fields of interest are emphasized.
Lewis, M. H.↗
Design of a horizonal liquid helium cryostat for refrigerating a flying superconducting magnet in a wind tunnel
The design of a horizontal liquid helium cryostat for refrigerating a flying superconducting magnet in a wind tunnel is presented. The basic principles of magnetic suspension theory are described and theoretical calculations of the superconducting magnet are provided. The experimental results of the boil-off of liquid nitrogen and liquid helium in the cryostat are reported.
Wu, Y. Y.↗
LANDSAT-4 horizon scanner full orbit data averages
Averages taken over full orbit data spans of the pitch and roll residual measurement errors of the two conical Earth sensors operating on the LANDSAT 4 spacecraft are described. The variability of these full orbit averages over representative data throughtout the year is analyzed to demonstrate the long term stability of the sensor measurements. The data analyzed consist of 23 segments of sensor measurements made at 2 to 4 week intervals. Each segment is roughly 24 hours in length. The variation of full orbit average as a function of orbit within a day as a function of day of year is examined. The dependence on day of year is based on association the start date of each segment with the mean full orbit average for the segment. The peak-to-peak and standard deviation values of the averages for each data segment are computed and their variation with day of year are also examined.
Stanley, J. P.↗