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Pritchard, E. B.

Publications and source records attributed to Pritchard, E. B..

At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1992

Mars: Past, present, and future; Proceedings of the Conference, Williamsburg, VA, July 16-19, 1991

The present conference discusses the terraforming of Mars, the history of the Viking lander efforts, prospective Mars exploration management and research initiatives in view of the Viking Missions, the rationale and constituencies for NASA's Space Exploration Initiative, Mars mission benefits, and a Congressional perspective on the Space Exporation initiative. Also discussed are a risk-based approach to robotic mission requirements, a Mars Environment Survey Mission concept, a Mars network of surface stations, Mars sample-return mission options, an integrated STS for Mars exploration, nuclear propulsion technology development by NASA/DOE, radiation shielding en route to Mars and on the surface, advanced technologies for nuclear propulsion, and 'smart' space suits for space exploration.

Pritchard, E. B.↗
NASA NTRS1992

Establishing the infrastructure - Orbital operational requirements and options

Manned missions currently under consideration for exploration of the moon and Mars entail supporting activities in LEO. Attention is presently given to the significance of NASA's Space Station Freedom for both the support of lunar base-building efforts and the gathering of expertise for such ambitious undertakings. The lunar base infrastructure is expected to in turn play a similar technology-validating and operations-supporting role for manned exploration of Mars. Attention is given to the incorporation of aerobrake construction facilities by Space Station Freedom.

Pritchard, E. B.↗
NASA NTRS1986

Space Station design for growth

This paper reviews the current status of Space Station planning for growth as the basis of an assessment of potential Space Station evolution directions in the 21st Century to meet the challenges of the report of the U.S. National Commission on space, 'Pioneering the Space Frontier'. Thus future mission requirements are reviewed and assessed. Based on these requirements, evolution scenarios and potential configurations are developed. It is concluded that the Space Station, as a multipurpose facility, should evolve to a capability of 300 kW, crew of 18 and 5 lab modules. Beyond this capability it will be necessary to separate functions and establish two separate Space Stations, one for research and one for operational activities (e.g., transportation node, servicing, etc.). If the U.S. National Commission on space's recommendations are adopted, this separation or 'branching' could occur as early as 2005 to meet the needs of a permanent lunar base.

Pritchard, E. B.↗
NASA NTRS1985

Potential space station evolution and growth modes

User requirements for the first ten years of space station operation are assessed, and space station system capabilities to meet those needs are delineated. A module length of about 11.5 m with external interconnects best meets growth needs, and a power unit which provides 42 KW is desirable. Four growth scenarios for the manned element of the space station program are studied, and typical growth configurations are described. The full dual keel configuration is attractive at this point due to its increased flexibility.

Pritchard, E. B.↗
NASA NTRS1983

Overview of NASA space station activities

The architecture, functions, and human activities on-board a space station are discussed. A manned presence is regarded as essential for innovative actions and successful exploitation of weightless conditions. The station itself could be a cluster of modules for habitation, power, operations, docking, experimentation, and storage. Additionally, the station could provide an interface for free-flying platforms and teleoperated satellite services, as well as a base for establishing space-based manufacturing facilities. NASA has projected timelines that include initial development funding in 1987, full capabilities before the year 2000, and initial costs for minimum capabilities of $7.5-9 billion. Architecture, mission requirements, trade-offs, and concepts are currently being defined as a prelude to systems development. Attention is being given to participation by both the DoD and other governments, and to defining the capabilities of the station, including habitability, closed-loop life-support system, the scope of science application and data transfer, and the power requirements.

Tilton, E. L., III↗
NASA NTRS1983

Space station needs, attributes, and architectural options. Volume 1. Executive summary

The initial space station should be manned, placed in 28.5 deg orbit, and provide substantial economic, performance, and social benefits. The most beneficial space station capabilities include: a space test facility; a transport harbor; satellite servicing and assembly; and an observatory. A space industrial park could be added once further development effort validates the cost and expanding commercial market for space processed materials. The potential accrued gross mission model benefit derived from these capabilities is $5.9B without the industrial park, and $9.3B with it. An unclassified overview of all phases of the study is presented.

Pritchard, E. B.↗
NASA NTRS1983

Integrated requirements for a space station

The time-phased mission set developed for the proposed space station program (including the manned facility, coorbiting and remote free flyers and platforms, orbital maneuvering and transfer systems, and storage and service facilities) by the Space Station Mission Requirements Workshop in May 1983, is presented in figures and tables and discussed. The scientific, commercial, and technology-development proposals are characterized, and the requirements for a station and coorbiting platform at 28.5-deg orbital inclination are listed for the period 1991-2000. Japanese, ESA, and Canadian utilization is considered, special requirements are outlined, and functional characteristics are summarized. Developmental strategies to meet the concerns of the user community are suggested.

Pritchard, E. B.↗
NASA NTRS1981

Analysis of ALOPE data from Superflux

Remote sensing data collected with the airborne lidar oceanographic probing experiment (ALOPE) laser fluorosensor during the Superflux 1 and Superflux 2 experiments were analyzed using two techniques. A qualitative technique which requires no supplementary data provided a near-real-time estimate of relative abundance of the golden-brown and green phytoplankton color groups. Contour plots developed for the later mission are used to demonstrate the utility of this technique. A quantitative technique which requires supplementary data to define the attenuation coefficient provides chlorophyll a concentration by color group. The sum of the golden-brown and green chlorophyll a data yields total chlorophyll a values which may be compared with in situ data. As expected, the golden-brown population was dominant in the Chesapeake Bay and the Bay plume whereas the green population was dominant in shelf waters.

Jarrett, O., Jr.↗
NASA NTRS1981

Aerospace remote sensing of the coastal zone for water quality and biotic productivity applications

Remote sensing can provide the wide area synoptic coverage of surface waters which is required for studies of such phenomena as river plume mixing, phytoplankton dynamics, and pollutant transport and fate, but which is not obtainable by conventional oceanographic techniques. The application of several remote sensors (aircraftborne and spacecraftborne multispectral scanners, passive microwave radiometers, and active laser systems) to coastal zone research is discussed. Current measurement capabilities (particulates, chlorophyll a, temperature, salinity, ocean dumped materials, other pollutants, and surface winds and roughness) are defined and the results of recent remote sensing experiments conducted in the North Atlantic coastal zone are presented. The future development of remote sensing must rely on an integrated laboratory research program in optical physics. Recent results indicate the potential for separation of particulates into subsets by remote sensors.

Pritchard, E. B.↗
NASA NTRS1974

Orbital and entry tracking accessory for globes

An orbital and entry tracking accessory or attachment is described which can be mounted on a globe to provide a rapid means of determining range requirements for entry vehicles returning from any orbit to any desired landing site with reasonable accuracy. The device is constructed of clear plastic strip material, and comprises a support ring, a calibrated orbital track member rigidly carried by the support ring, and a calibrated lateral range member pivotally coupled to the support ring at points such that the lateral range member is always oriented normally to the orbital track member. The assembly is mountable on the globe relatively snugly, but freely movable. At least one of the members has a detachable coupling which permits placement of the device on the globe.

Pritchard, E. B.↗
NASA NTRS1974

Options for Mars exploration

The many possible post-Viking 1975 Mars mission options are explored. These include small atmospheric probe/landers (adaptations of the Venus Pioneer to Mars), repeat Vikings with and without science changes, long-life orbiters to provide coverage of both hemispheres for a full Martian year, small rovers deployed from the Viking lander with ranges of up to 1 km from it, large autonomous rovers, Mars sample-return missions and, finally, missions to the satellites of Mars, including sample return. The examination includes energy requirements and time frames.

Pritchard, E. B.↗
NASA NTRS1971

Phobos/Deimos missions

Phobos and Deimos missions, examining lander and lander/orbiter configurations and Titan- Centaur and space shuttle-Centaur launch systems

Harrison, E. F.↗
NASA NTRS1970

Orbit, reentry, and landing attachment for globes

Navigational device, invented to aid recovery of spacecraft from any orbit, also illustrates motions of satellites relative to earth and their entry-ranging requirements. Device rapidly and accurately defines lateral range requirements for spacecraft returning to any desired site without manual or computerized calculation of orbital equations of motion.

Pritchard, E. B.↗