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At least 415 records · Page 23

The growth of materials processing in space - A history of government support for new technology

Development of a given technology for national defense and large systems developments when the task is too large or risky for entrepreneurs, yet is clearly in the best interest of the nation are discussed. Advanced research to identify areas of interest was completed. Examples of commercial opportunities are the McDonnell-Douglas Corporation purification process for pharmaceutical products and the Microgravity Research Associates process for growing gallium arsenide crystals in space.

Mckannan, E. C.↗

Chronology of KSC and KSC related events for 1983

Materials for this chronology were selected from Aviation Week and Space Technology, Defense Daily, Miami Herald, Sentinel Star (Orlando), Today (Cocoa), Spaceport News (KSC), NASA News Releases, and other sources. The document is intended to serve as a record of KSC events and as a reference source for historians and other researchers. Arrangement is by month; items are by date of the published sources. Actual date of the event may be indicated in parenthesis, when the article itself does not make that information explicit.

Nail, K., Jr.↗

Status of the National Space Transportation System

The National Space Transportation System is a national resources serving the government, Department of Defense and commercial needs of the USA and others. Four orbital flight tests were completed July 4, 1982, and the first Operational Flight (STS-5) which placed two commercial communications into orbit was conducted November 11, 1982. February 1983 marked the first flight of the newest orbiter, Challenger. Planned firsts in 1983 include: use of higher performance main engines and solid rocket boosters, around-the-clock crew operations, a night landing, extra-vehicular activity, a dedicated DOD mission, and the first flight of a woman crew member. By the end of 1983, five commercial payloads and two tracking and data relay satellites should be deployed and thirty-seven crew members should have made flights aboard the space shuttle.

Abrahamson, J. A.↗

NORAD operational system

There are three aspects to the Space Defense Mission: satellite surveillance, satellite protection and satellite negation. The focus of this report is on space surveillance and detection as currently accomplished by both ground and space based assets. The evolution of the space surveillance system is described. The characteristics of the current space surveillance system are also described.

Brach, D.↗

Air Force satellite position management

The Space Act of 1958 identified the Department of Defense as responsible for conducting military operations in space. Subsequently, the United States Air Force was assigned to act as the DOD's executive agent for space. In addition, the Air Force is responsible for acquisition and launch of DOD space systems. Within the Air Force, space related roles and activities have been delegated to several subordinate organizations and agencies. The roles and responsibilities of agencies are still evolving. The Air Force has designated the Air Force System Command's Space Division as its office of primary responsibility for satellite position management. Spacecraft program offices at Space Division are required by regulation to include position management planning in both prelaunch and orbital phases of spacecraft development and operation.

Davis, R.↗

Spacecraft environmental interactions: A joint Air Force and NASA research and technology program

A joint Air Force/NASA comprehensive research and technology program on spacecraft environmental interactions to develop technology to control interactions between large spacecraft systems and the charged-particle environment of space is described. This technology will support NASA/Department of Defense operations of the shuttle/IUS, shuttle/Centaur, and the force application and surveillance and detection missions, planning for transatmospheric vehicles and the NASA space station, and the AFSC military space system technology model. The program consists of combined contractual and in-house efforts aimed at understanding spacecraft environmental interaction phenomena and relating results of ground-based tests to space conditions. A concerted effort is being made to identify project-related environmental interactions of concern. The basic properties of materials are being investigated to develop or modify the materials as needed. A group simulation investigation is evaluating basic plasma interaction phenomena to provide inputs to the analytical modeling investigation. Systems performance is being evaluated by both groundbased tests and analysis.

Pike, C. P.↗

Activities of the Jet Propulsion Laboratory, 1 January - 31 December 1983

There are many facets to the Jet Propulsion Laboratory, for JPL is an organization of multiple responsibilities and broad scope, of diverse talents and great enterprise. The Laboratory's philosophy, mission, and goals have been shaped by its ties to the California Institute of Technology (JPL's parent organization) and the National Aeronautics and Space Administration (JPL's principal sponsor). JPL's activities for NASA in planetary, Earth, and space sciences currently account for almost 75 percent of the Laboratory's overall effort. JPL Research activities in the following areas are discussed: (1) deep space exploration; (2) telecommunications systems; (3) Earth observations; (4) advanced technology; (5) defense programs; and (6) energy and technology applications.

Source record↗

Deep reconditioning of batteries during DSCS 3 flight operations

Deep reconditioning of batteries is defined as discharge below the 1.0 volt/cell level to a value of about 1.0 volt/battery. This type of reconditioning was investigated for use on the Defense Satellite Communications System (DSCS) spacecraft, and has been used during the first year of orbital operation. Prior to launch of the spacecraft, the deep reconditioning was used during the battery life test, which has now complete fourteen eclipse periods. Reconditioning was performed prior to each eclipse period of the life test, and is scheduled to be used prior to each eclipse period in orbit. The battery data for discharge and recharge is presented for one of the life test reconditioning cycles, and for each of the three batteries during the reconditioning cycles between eclipse period no.1 and eclipse period no.2 in Earth orbit.

Thierfelder, H. E.↗

Advanced beamed-energy and field propulsion concepts

Specific phenomena which might lead to major advances in payload, range and terminal velocity of very advanced vehicle propulsion are studied. The effort focuses heavily on advanced propulsion spinoffs enabled by current government-funded investigations in directed-energy technology: i.e., laser, microwave, and relativistic charged particle beams. Futuristic (post-year 2000) beamed-energy propulsion concepts which indicate exceptional promise are identified and analytically investigated. The concepts must be sufficiently developed to permit technical understanding of the physical processes involved, assessment of the enabling technologies, and evaluation of their merits over conventional systems. Propulsion concepts that can be used for manned and/or unmanned missions for purposes of solar system exploration, planetary landing, suborbital flight, transport to orbit, and escape are presented. Speculations are made on the chronology of milestones in beamed-energy propulsion development, such as in systems applications of defense, satellite orbit-raising, global aerospace transportation, and manned interplanetary carriers.

Myrabo, L. N.↗

Six mechanisms used on the SSM/1 radiometer

Future USAF Block 5D Defense Meteorological Satellites will carry a scanning microwave radiometer sensor (SSM/1). SSM/1 senses the emission of microwave energy and returns to earth data used to determine weather conditions, such as rainfall rates, soil moisture, and oceanic wind speed. The overall design of the SSM/1 radiometer was largely influenced by the mechanisms. The radiometer was designed to be stowed in a cavity on the existing spacecraft. The deployment of the sensor is complex due to the constraint of this cavity and the need for precision in the deployment. The radiometer will continuously rotate, instead of oscillate, creating the need for a bearing and power transfer assembly and a momentum compensation device. The six mechanisms developed for this program are described.

Ludwig, H. R.↗

Air-sea interaction with SSM/I and altimeter

A number of important developments in satellite remote sensing techniques have occurred recently which offer the possibility of studying over vast areas of the ocean the temporally evolving energy exchange between the ocean and the atmosphere. Commencing in spring of 1985, passive and active microwave sensors that can provide valuable data for scientific utilization will start to become operational on Department of Defense (DOD) missions. The passive microwave radiometer can be used to estimate surface wind speed, total air column humidity, and rain rate. The active radar, or altimeter, senses surface gravity wave height and surface wind speed.

Source record↗

Satellite communication antenna technology

A general overview of current technology in the field of communication satellite antennas is presented. Among the topics discussed are: the design of multiple beam systems; frequency reuse; and polarization control of antenna measurements. Consideration is also given to: contour beam synthesis; dual shaped reflector synthesis; beam shaping; and offset reflector design. The applications of the above technologies to present and future generations of communications satellites is considered, with emphasis given to such systems as: the Intelsats; the Defense Satellite Communications System, (DSCS-III); Satellite Business System (SBS), and Comstar.

Mittra, R.↗

Synoptic cryosphere-atmosphere interactions in the Northern Hemisphere from DMSP image analysis

A climatology of Northern Hemisphere cyclonic cloud vortices is developed from high-resolution Defense Meteorological Satellite Program (DMSP) infrared imagery for mid-season months. The technique which is described involves pattern recognition using a detailed vortex classification system. Variations in hemispheric frequencies of successive vortex types are dominantly seasonal rather than latitudinal and imply a close association with surface (mainly cryosphere) variations. More extensive sea ice or snow cover in April and January is associated with increased cyclogenesis, indicating enhanced surface-atmosphere feedback. A significant relationship exists between cloud-vortex variations and the sea ice boundary, but not with the continental snowline.

Carleton, A. M.↗

A comparison of precipitating electron energy flux on March 22, 1979 with an empirical model - CDAW 6

Data recorded by Defense Meteorological Satellite Program, Tiros and P-78-1 satellites for the CDAW 6 event on March 22, 1979, have been compared with a statistical model of precipitating electron fluxes. Comparisons have been made on both an orbit-by-orbit basis and on a global basis by sorting and binning the data by AE index, invariant latitude, and magnetic local time in a manner similar to which the model was generated. It is concluded that the model flux agrees with the data to within a factor of two, although small features and the exact locations of features are not consistently reproduced. In addition, the latitude of highest electron precipitation usually occurs about 3 deg more poleward in the model than in the data. This discrepancy is attributed to ring current inflation of the storm time magnetosphere.

Simons, S. L., Jr.↗

High-resolution X-ray spectra of solar flares. VII - A long-duration X-ray flare associated with a coronal mass ejection

It has been recognized that very long duration X-ray events (lasting several hours) are frequently associated with coronal mass ejection. Thus, Sheeley et al. (1983) found that the probability of the occurrence of a coronal mass ejection (CME) increases monotonically with the X-ray event duration time. It is pointed out that the association of long-duration, or long-decay, X-ray events (LDEs) with CMEs was first recognized from analysis of solar images obtained by the X-ray telescopes on Skylab and the Naval Research Laboratory (NRL) slitless spectroheliograph. Recently high-resolution Bragg crystal X-ray spectrometers have been flown on three spacecraft, including the Department of Defense P78-1 spacecraft, the NASA Solar Maximum Mission (SMM), and the Japanese Hinotori spacecraft. In the present paper, P78-1 X-ray spectra of an LDE which had its origin behind the solar west limb on November 14, 1980 is presented. The obtained data make it possible to estimate temperatures of the hottest portion of the magnetic loops in which the emission arises.

Kreplin, R. W.↗

Parallel processor programs in the Federal Government

In 1982, a report dealing with the nation's research needs in high-speed computing called for increased access to supercomputing resources for the research community, research in computational mathematics, and increased research in the technology base needed for the next generation of supercomputers. Since that time a number of programs addressing future generations of computers, particularly parallel processors, have been started by U.S. government agencies. The present paper provides a description of the largest government programs in parallel processing. Established in fiscal year 1985 by the Institute for Defense Analyses for the National Security Agency, the Supercomputing Research Center will pursue research to advance the state of the art in supercomputing. Attention is also given to the DOE applied mathematical sciences research program, the NYU Ultracomputer project, the DARPA multiprocessor system architectures program, NSF research on multiprocessor systems, ONR activities in parallel computing, and NASA parallel processor projects.

Schneck, P. B.↗

Space Shuttle security policies and programs

The Space Shuttle vehicle consists of the orbiter, external tank, and two solid rocket boosters. In dealing with security two major protective categories are considered, taking into account resource protection and information protection. A review is provided of four basic programs which have to be satisfied. Aspects of science and technology transfer are discussed. The restrictions for the transfer of science and technology information are covered under various NASA Management Instructions (NMI's). There were two major events which influenced the protection of sensitive and private information on the Space Shuttle program. The first event was a manned space flight accident, while the second was the enactment of a congressional bill to establish the rights of privacy. Attention is also given to national resource protection and national defense classified operations.

Keith, E. L.↗

Global view of the upper level outflow patterns associated with tropical cyclone intensity changes during FGGE

The characteristics of the upper tropospheric outflow patterns which occur with tropical cyclone intensification and weakening over all of the global tropical cyclone basins during the year long period of the First GARP Global Experiment (FGGE) are discussed. By intensification is meant the change in the tropical cyclone's maximum wind or central pressure, not the change of the cyclone's outer 1 to 3 deg radius mean wind which we classify as cyclone strength. All the 80 tropical cyclones which existed during the FGGE year are studied. Two-hundred mb wind fields are derived from the analysis of the European Center for Medium Range Weather Forecasting (ECMWF) which makes extensive use of upper tropospheric satellite and aircraft winds. Corresponding satellite cloud pictures from the polar orbiting U.S. Defense Meteorological Satellite Program (DMSP) and other supplementary polar and geostationary satellite data are also used.

Chen, L.↗