Concordia Station, Dome C, Antarctica as a Ground-Based Analog for Spaceflight/Planetary Exploration: The CHOICE* Immunology Study
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Crucian, Brian↗
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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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Wireless Instrumentation System and Power Management Scheme Therefore
A wireless instrumentation system enables a plurality of low power wireless transceivers to transmit measurement data from a plurality of remote station sensors to a central data station accurately and reliably. The system employs a relay based communications scheme where remote stations that cannot communicate directly with the central station due to interference, poor signal strength, etc., are instructed to communicate with other of the remote stations that act as relays to the central station. A unique power management scheme is also employed to minimize power usage at each remote station and thereby maximize battery life. Each of the remote stations prefembly employs a modular design to facilitate easy reconfiguration of the stations as required.
Perotti, Jose↗
Exobiology experiment concepts for space station
The exobiology discipline uses ground based and space flight resources to conduct a multidiscipline research effort dedicated to understanding fundamental questions about the origin, evolution, and distribution of life and life related molecules throughout the universe. Achievement of this understanding requires a methodical research strategy which traces the history of the biogenic elements from their origins in stellar formation processes through the chemical evolution of molecules essential for life to the origin and evolution of primitive and, ultimately, complex living species. Implementation of this strategy requires the collection and integration of data from solar system exploration spacecraft and ground based and orbiting observatories and laboratories. The Science Lab Module (SLM) of the Space Station orbiting complex may provide an ideal setting in which to perform certain classes of experiments which form the cornerstone of exobiology research. These experiments could demonstrate the pathways and processes by which biomolecules are synthesized under conditions that simulate the primitive Earth, planetary atmospheres, cometary ices, and interstellar dust grains. Exobiology experiments proposed for the Space Station generally fall into four classes: interactions among gases and grains (nucleation, accretion, gas-grain reactions), high energy chemistry for the production of biomolecules, physical and chemical processes occurring on an artificial comet, and tests of the theory of panspermia.
Griffiths, L. D.↗
Critical issues in NASA information systems
The National Aeronautics and Space Administration has developed a globally-distributed complex of earth resources data bases since LANDSAT 1 was launched in 1972. NASA envisages considerable growth in the number, extent, and complexity of such data bases, due to the improvements expected in its remote sensing data rates, and the increasingly multidisciplinary nature of its scientific investigations. Work already has begun on information systems to support multidisciplinary research activities based on data acquired by the space station complex and other space-based and terrestrial sources. In response to a request from NASA's former Associate Administrator for Space Science and Applications, the National Research Council convened a committee in June 1985 to identify the critical issues involving information systems support to space science and applications. The committee has suggested that OSSA address four major information systems issues; centralization of management functions, interoperability of user involvement in the planning and implementation of its programs, and technology.
Source record↗
Exobiology experiment concepts for Space Station
The exobiology discipline uses ground based and space flight resources to conduct a multidiscipline research effort dedicated to understanding fundamental questions about the origin, evolution, and distribution of life and life related molecules throughout the universe. Achievement of this understanding requires a methodical research strategy which traces the history of the biogenic elements from their origins in stellar formation processes through the chemical evolution of molecules essential for life to the origin and evolution of primitive and, ultimately, complex living species. Implementation of this strategy requires the collection and integration of data from solar system exploration spacecraft and ground based and orbiting observatories and laboratories. The Science Lab Module (SLM) of the Space Station orbiting complex may provide an ideal setting in which to perform certain classes of experiments which form the cornerstone of exobiology research. These experiments could demonstrate the pathways and processes by which biomolecules are synthesized under conditions that stimulate the primitive earth, planetary atmospheres, cometary ices, and interstellar dust grains. Exobiology experiments proposed for the Space Station generally fall into four classes: interactions among gases and grains (nucleation, accretion, gas-grain reactions), high energy chemistry for the production of biomolecules, physical and chemical processes occurring on an artificial comet, and tests of the theory of panspermia.
Griffiths, Lynn D.↗
Using space for technology development - Planning for the Space Station era
Experience with the Shuttle and free-flying satellites as technology test-beds has shown the feasibility and desirability of using space assets as a facility for technology development. Thus, by the time the Space Station era will have arrived, the technologist will be ready for an accessible engineering facility in space. As the 21st century is approached, it is expected that virtually every flight to the Space Station Freedom will be required to carry one or more research, technology, and engineering experiments. The experiments planned will utilize both the pressurized volume, and the external payload attachment facilities. A unique, but extremely important, class of experiments will use the Space Station itself as an experimental vehicle. Based upon recent examination of possible Space Station Freedom assembly sequences, technology payloads may well utilize 20-30 percent of available resources.
Ambrus, Judith H.↗
Towards Plume Impingement Modeling in Space Environments
After 30 years human presence in low-earth orbit, NASA is returning to the moon and eventually will go to Mars. To this end, NASA is constructing the Lunar Gateway, an ISS-like space station to act as a home base for Lunar exploration. A large space station must be assembled while in orbit, using a “piecemeal” approach. In this context, it means that the different modules will arrive at different times and attach to what is already in service. The ISS provides an excellent example of this approach, and the proposed Lunar Gateway will undergo a similar assembly process. This assembly is achieved via “docking” maneuvers between modules, which are made possible by sequential firings of the onboard reaction control system (RCS) thrusters. They work by firing hot gases to produce adverse thrust and the needed change in velocity to safely finish the docking approach. The issue is that the gas from these thrusters' forms flow structures described as “plumes” and can impinge onto the outer surfaces of the space station, causing unwanted forces and moments, heat loads, sediment deposition, and in extreme cases, even surface erosion. All mechanisms that can damage the space station and must be avoided. Both permanent and visiting modules will have these RCS thruster exhaust impingement problems. Accurately and efficiently modeling these plume is an involved multi-physics calculation but also an important tool when designing the control algorithms of approaching modules. This poster presents progress towards this simulation on two fronts. First is the verification of OpenFOAM for rarefied plume impingement calculations by direct comparison to published DAC cases. Second is the estimation of plume impingement strikes over the time scale of an entire docking event. This is done by using a simple plume source flow model and a prescribed motion visualizer—coded in Python. Together these tools help push NASA's capabilities for simulating these plume impingement effects.
Rarefied Flows↗
GPS Monitor Station Upgrade Program at the Naval Research Laboratory
One of the measurements made by the Global Positioning System (GPS) monitor stations is to measure the continuous pseudo-range of all the passing GPS satellites. The pseudo-range contains GPS and monitor station clock errors as well as GPS satellite navigation errors. Currently the time at the GPS monitor station is obtained from the GPS constellation and has an inherent inaccuracy as a result. Improved timing accuracy at the GPS monitoring stations will improve GPS performance. The US Naval Research Laboratory (NRL) is developing hardware and software for the GPS monitor station upgrade program to improve the monitor station clock accuracy. This upgrade will allow a method independent of the GPS satellite constellation of measuring and correcting monitor station time to US Naval Observatory (USNO) time. THe hardware consists of a high performance atomic cesium frequency standard (CFS) and a computer which is used to ensemble the CFS with the two CFS's currently located at the monitor station by use of a dual-mixer system. The dual-mixer system achieves phase measurements between the high-performance CFS and the existing monitor station CFS's to within 400 femtoseconds. Time transfer between USNO and a given monitor station is achieved via a two way satellite time transfer modem. The computer at the monitor station disciplines the CFS based on a comparison of one pulse per second sent from the master site at USNO. The monitor station computer is also used to perform housekeeping functions, as well as recording the health status of all three CFS's. This information is sent to the USNO through the time transfer modem. Laboratory time synchronization results in the sub nanosecond range have been observed and the ability to maintain the monitor station CFS frequency to within 3.0 x 10 (sup minus 14) of the master site at USNO.
Galysh, Ivan J.↗
Lunar mission safety and rescue: Escape/rescue analysis and plan
The results are presented of the technical analysis of escape/rescue/survival situations, crew survival techniques, alternate escape/rescue approaches and vehicles, and the advantages and disadvantages of each for advanced lunar exploration. Candidate escape/rescue guidelines are proposed and elements of a rescue plan developed. The areas of discussions include the following: lunar arrival/departure operations, lunar orbiter operations, lunar surface operations, lunar surface base escape/rescue analysis, lander tug location operations, portable airlock, emergency pressure suit, and the effects of no orbiting lunar station, no lunar surface base, and no foreign lunar orbit/surface operations on the escape/rescue plan.
Source record↗
Adaption of space station technology for lunar operations
Space Station Freedom technology will have the potential for numerous applications in an early lunar base program. The benefits of utilizing station technology in such a fashion include reduced development and facility costs for lunar base systems, shorter schedules, and verification of such technology through space station experience. This paper presents an assessment of opportunities for using station technology in a lunar base program, particularly in the lander/ascent vehicles and surface modules.
Garvey, J. M.↗
A magnetic isolation and pointing system for the astrometric telescope facility
The astrometric telescope facility (ATF), a 20-meter telescope designed for long-term detection and observation of planetary systems outside of the solar system, is scheduled to be a major user of the Space Station's payload pointing system (PPS) capabilities. However, because the ATF has such a stringent pointing stability specification (as low as 0.01 arcsec error over the frequency range from 5 to 200 hertz) and requires +/- 180-degree roll rotation around the telescope's line of sight, the ATF's utilization of the PPS requires the addition of a mechanism or mechanisms to enhance the basic PPS capabilities. The results of a study conducted to investigate the ATF pointing performance achievable by the addition of a magnetic isolation and pointing (MIPS) system between the PPS upper gimbal and the ATF, and separately, by the addition of a passive isolation system between the Space Station and the PPS base are presented. In addition, the study produced requirements on magnetic force and gap motion as a function of the level of Space Station disturbance. These results were used to support the definition of a candidate MIPS. Pointing performance results from the study indicate that a MIPS can meet the ATF pointing requirements in the presence of a PPS base transitional acceleration of up to 0.018g, with reasonable restrictions placed on the isolation and pointing bandwidths. By contrast, the passive base isolator system must have an unrealistically low isolation bandwidth on all axes (less than 0.1 hertz) to meet ATF pointing requirements. The candidate MIPS is based on an assumed base translational disturbance of 0.01g. The system fits within the available annular region between the PPS and ATF while meeting power and weight limitations and providing the required payload roll motion. Payload data and power services are provided by noncontacting transfer devices.
Smith, Marcie↗
Concepts for manned lunar habitats
The design philosophy that will guide the design of early lunar habitats will be based on a compromise between the desired capabilities of the base and the economics of its development and implantation. Preferred design will be simple, make use of existing technologies, require the least amount of lunar surface preparation, and minimize crew activity. Three concepts for an initial habitat supporting a crew of four for 28 to 30 days are proposed. Two of these are based on using Space Station Freedom structural elements modified for use in a lunar-gravity environment. A third concept is proposed that is based on an earlier technology based on expandable modules. The expandable modules offer significant advantages in launch mass and packaged volume reductions. It appears feasible to design a transport spacecraft lander that, once landed, can serve as a habitat and a stand-off for supporting a regolith environmental shield. A permanent lunar base habitat supporting a crew of twelve for an indefinite period can be evolved by using multiple initial habitats. There appears to be no compelling need for an entirely different structure of larger volume and increased complexity of implantation.
Hypes, W. D.↗
Charter for Systems Engineer Working Group
This charter establishes the International Space Station Program (ISSP) Mobile Servicing System (MSS) Systems Engineering Working Group (SEWG). The MSS SEWG is established to provide a mechanism for Systems Engineering for the end-to-end MSS function. The MSS end-to-end function includes the Space Station Remote Manipulator System (SSRMS), the Mobile Remote Servicer (MRS) Base System (MBS), Robotic Work Station (RWS), Special Purpose Dexterous Manipulator (SPDM), Video Signal Converters (VSC), and Operations Control Software (OCS), the Mobile Transporter (MT), and by interfaces between and among these elements, and United States On-Orbit Segment (USOS) distributed systems, and other International Space Station Elements and Payloads, (including the Power Data Grapple Fixtures (PDGFs), MSS Capture Attach System (MCAS) and the Mobile Transporter Capture Latch (MTCL)). This end-to-end function will be supported by the ISS and MSS ground segment facilities. This charter defines the scope and limits of the program authority and document control that is delegated to the SEWG and it also identifies the panel core membership and specific operating policies.
Suffredini, Michael T.↗
Agent-Based Simulation of Price-Demand Dynamics in Multi-Service Charging Station
As the adoption of electric vehicles and hydrogen fuel-cell vehicles grows, understanding how dynamic pricing strategies influence charging and refueling behaviors becomes crucial for optimizing local energy markets. This paper proposes a simulation-based analysis of a hydrogen-electricity integrated charging station that serves both types of vehicles. A multi-agent simulation framework is developed to model the interactions between vehicles and the station, incorporating price- and delay-sensitive behaviors in decision-making. The station can dynamically adjust energy prices, while vehicles optimize their charging or refueling choices based on their utility values. A series of sensitivity analyses are conducted to evaluate how electricity pricing, infrastructure capacity, and waiting behavior impact station performance. Results highlight that moderate electricity prices maximize user participation without sacrificing profit, infrastructure should be right-sized to demand to avoid over- or underutilization, and delay-toleration also affects service outcomes, which may reach the maximum service coverage at the threshold of 45 minutes.
Wang, Xudong [University of Tennessee, Knoxville (↗
Polar Satcom System and Related Method
A system and method for communication relay via a repeater platform satellite vehicle to a near surface station in the Polar Region is disclosed. A preferred embodiment receives a plurality of positioning and content data from a plurality of constellations of Geosynchronous Equatorial Orbit (GEO) Satellite Vehicles (SAT). Additionally, the system receives a plurality of position, time and altitude data from constellations of available repeater platform (RP) SATs. The system receives a request for content from a near surface station located in an area lacking adequate line-of-sight to the GEO based signal. The system aligns antenna elements onboard the desired RP SATs to amplify and relay the GEO based signal toward the near surface station and vice versa. Additionally, the system commands directional antenna elements onboard the station to send and receive the relayed signal making the GEO based content available to the near surface station.
Mitchell, James P.↗
Laser ranging application to time transfer using geodetic satellite and to other Japanese space programs
Communications Research Laboratory (CRL) has been developing a laser time transfer system using a satellite laser ranging (SLR) system. We propose Japanese geodetic satellite 'AJISAI', launched in 1986 as a target satellite. The surface is covered not only with corner cube reflectors but also with mirrors. The mirrors are originally designed for observation of flushing solar light reflected by the separate mirrors while the satellite is spinning. In the experiment, synchronized laser pulses are transferred via specified mirror from one station to another while the satellite is up on the horizon to both stations. The system is based on the epoch timing ranging system with 40 ps ranging precision, connected together with UTC(CRL). Simulation study indicates that two stations at thousands of km distance from each other can be linked with signal strength of more than 10 photons and the distributed images of laser beam from AJISAI mirrors give many chances for two stations to link each other during a single AJISAI pass. Retro-reflector In Space for Advanced Earth Observation Satellite (ADEOS) and RendDezVous docking mission of Experimental Technology Satellite-7 (ETS-7) are briefly presented.
Kunimori, Hiroo↗
Hollow cathode heater development for the Space Station plasma contactor
A hollow cathode-based plasma contactor has been selected for use on the Space Station. During the operation of the plasma contactor, the hollow cathode heater will endure approximately 12000 thermal cycles. Since a hollow cathode heater failure would result in a plasma contactor failure, a hollow cathode heater development program was established to produce a reliable heater design. The development program includes the heater design, process documents for both heater fabrication and assembly, and heater testing. The heater design was a modification of a sheathed ion thruster cathode heater. Three heaters have been tested to date using direct current power supplies. Performance testing was conducted to determine input current and power requirements for achieving activation and ignition temperatures, single unit operational repeatability, and unit-to-unit operational repeatability. Comparisons of performance testing data at the ignition input current level for the three heaters show the unit-to-unit repeatability of input power and tube temperature near the cathode tip to be within 3.5 W and 44 degrees C, respectively. Cyclic testing was then conducted to evaluate reliability under thermal cycling. The first heater, although damaged during assembly, completed 5985 ignition cycles before failing. Two additional heaters were subsequently fabricated and have completed 3178 cycles to date in an on-going test.
Soulas, George C.↗
Status of Hollow Cathode Heater Development for the Space Station Plasma Contactor
A hollow cathode-based plasma contactor has been selected for use on the Space Station. During the operation of the plasma contactor, the hollow cathode heater will endure approximately 12000 thermal cycles. Since a hollow cathode heater failure would result in a plasma contactor failure, a hollow cathode heater development program was established to produce a reliable heater. The development program includes the heater design, process documents for both heater fabrication and assembly, and heater testing. The heater design was a modification of a sheathed ion thruster cathode heater. Heater tests included testing of the heater unit alone and plasma contactor and ion thruster testing. To date, eight heaters have been or are being processed through heater unit testing, two through plasma contactor testing and three through ion thruster testing, all using direct current power supplies. Comparisons of data from heater unit performance tests before cyclic testing, plasma contactor tests, and ion thruster tests at the ignition input current level show the average deviation of input power and tube temperature near the cathode tip to be +/-0.9 W and +/- 21 C, respectively. Heater unit testing included cyclic testing to evaluate reliability under thermal cycling. The first heater, although damaged during assembly, completed 5985 ignition cycles before failing. Four additional heaters successfully completed 6300, 6300, 700, and 700 cycles. Heater unit testing is currently ongoing for three heaters which have to date accumulated greater than 7250, greater than 5500, and greater than 5500 cycles, respectively.
Soulas, George C.↗