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An update on the Space Exploration Initiative (SEI) is given in viewgraph form. Topics covered include the key prerequisites of human exploration, project planning, Mars and lunar explorations, supporting technologies, near-term strategies for SEI, human support elements, and Space Station Freedom SEI accommodations.
Given here are the proceedings of the 3rd Space Exploration Initiative (SEI) Technical Interchange. Topics covered include the First Lunar Outpost (FLO), the Lunar Resource Mapper, lunar rovers, lunar habitat concepts, lunar shelter construction analysis, thermoelectric nuclear power systems for SEI, cryogenic storage, a space network for lunar communications, the moon as a solar power satellite, and off-the-shelf avionics for future SEI missions.
High level systems engineering modeling and analysis activities for the Space Exploration Initiative (SEI) are reviewed, with emphasis on planet surface systems. Particular attention is given to SEI studies, preliminary space robotic system requirements, and usefulness of space robotic systems developed to operate on planetary surfaces on earth. It is concluded that supervised intelligent systems on the planet surfaces are necessary to make SEI planet surface activities reliable and productive and encompass capabilities for control and monitoring of all elements, including supervised autonomous robotic systems. Amplification of human capabilities due to applying more knowledge and reasoning in more flexible and appropriate ways than conventional automation approaches will provide more robust performance, greater choice of interaction modes with operators, and greater transparency of operation.
The six sensors of SEIS (The Seismic Experiment for Interior Structure) [- one of three primary instruments on NASA's Mars Lander Insight] cover a broad range of the seismic bandwidth, from 0.01 hertz to 50 hertz, with possible extension to longer periods. Data are transmitted in the form of three continuous VBB (Very Broad-Band) components at 2 samples per second (sps), an estimation of the short period (SP) energy content from the SP at 1 sps, and a continuous compound VBB/SP vertical axis at 10 sps. The continuous streams are augmented by requested event data with sample rates from 20 to 100 sps. SEIS data products are downlinked from the spacecraft in raw CCSDS (Consultative Committee for Space Data Systems) packets and converted to both the Standard for the Exchange of Earthquake Data (SEED) format files and ASCII tables (GeoCSV) for analysis and archiving. Metadata are available in dataless SEED and StionXML. Time series data (waveforms) are available in miniseed and GeoCSV. Data are distributed according to FDSN (Federation of Digital Seismograph Networks - http://www.fdsn.org) formats and interfaces. Wind, pressure and temperature data from the Auxiliary Payload Sensor Suite (APSS) will also be available in SEED format, and can be used for decorrelation and diagnostic purposes on SEIS.
This paper will discuss the motivation and details of the implementation of the SEIS tether model and the ways in which the SEIS tether impacted placement accuracy in certain configurations. It will also show results from testing this model on Earth and deploying SEIS to the Martian surface on sol 22 of InSight’s mission.
This paper will discuss the motivation and details of the implementation of the SEIS tether model and the ways in which the SEIS tether impacted placement accuracy in certain configurations. It will also show results from testing this model on Earth and deploying SEIS to the Martian surface on sol 22 of InSight’s mission.
We have developed a prototype of tool support for risk assessment that uses selected components of the Software Engineering Institute (SEI) information, specifically: Capability Maturity Model (CMM) process activities, CMM process goals and the SEI taxonomy of software project risks.
The theoretical UV P Cygni profiles of the UV resonance lines for C IV, N V, Si IV, C III, and N IV of 26 O-type stars and one B star were calculated using the SEI method described by Lamers et al. (1987), taking into account the effects of turbulence in the wind, limb darkening, photospheric lines, and interstellar Ly alpha. The results were compared with profiles observed with the IUE satellite. The profile fits were found to be very accurate, showing significant improvement over previously obtained fits with the Sobolev (1958) method. The SEI method and the line fitting analysis are described and the results are presented in terms of the column densities and distributions of absorbing atoms, and the velocity laws.
To support the Space Exploration Initiative (SEI), a study was performed to investigate power system alternatives for the rover vehicles and servicers that were subsequently generated for each of these rovers and servicers, candidate power sources incorporating various power generation and energy storage technologies were identified. The technologies were those believed most appropriate to the SEI missions, and included solar, electrochemical, and isotope systems. The candidates were characterized with respect to system mass, deployed area, and volume. For each of the missions a preliminary selection was made. Results of this study depict the available power sources in light of mission requirements as they are currently defined.
The potentially complex missions of the Space Exploration Initiative (SEI) require advanced lunar communications, navigation, and information systems to provide voice, data, and image transmissions. The objectives here are to determine which SEI telecommunications applications will benefit from millimeter wave technology, assess the state of the art in millimeter wave technology, and describe the technology development shortfalls with respect to potential mission time frames. The assumptions for the analysis as well as other non-performance related issues are also presented.
A set of architectures for the Mars-earth SEI space communications link is identified and characterized. A 'road map' is defined that illustrates the most logical and efficient evolutionary paths for the SEI Mars-earth link. The major features of the road map include three alternative evolutionary paths meeting the data rate requirements that may grow from 10 Mbps to 1 Gbps in the 2008-2025 time frame. All three paths begin with a Ka-band MRS-EST baseline link in 2000, and diverge from this baseline as time progresses.
The potentially complex missions of the Space Exploration Initiative (SEI) require advanced lunar and Mars Telecommunications, Navigation, and Information Management (TNIM) systems to provide data, voice, and image transmissions. The objectives of the study are to determine which SEI telecommunications applications will benefit from millimeter wave technology, assess the state-of-the-art in millimeter wave technology and describe the technology development shortfalls with respect to potential mission time frames. The assumptions for the analysis as well as other issues, not related to performance, are also presented.
Results of the study performed to support the Space Exploration Initiative (SEI) which investigated power system alternatives for the rover vehicles and servicers that would be used for construction and operation of a lunar base is described. Using the mission requirements and power profiles that were subsequently generated for each of these rovers and servicers, candidate power sources incorporating various power generation and energy storage technologies were identified. The technologies were those believed most appropriate to the SEI missions, and included solar, electrochemical, and isotope systems. The candidates were characterized with respect to system mass, deployed area and volume. For each of the missions a preliminary selection was made. Results of this study depict the available power sources in light of the mission requirements as they are currently defined.
The use of the Space Station Freedom (SSF) for life sciences research is evaluated from the standpoint of requirements for the Space Exploration Initiative (SEI). SEI life sciences research encompasses: (1) biological growth and development in space; (2) life support and environmental health; (3) physiological/psychological factors of extended space travel; and (4) space environmental factors. The platforms required to support useful study in these areas are listed and include ground-based facilities, permanently manned spacecraft, and the Space Shuttle. The SSF is shown to be particularly applicable to the areas of research because its facilities can permit the study of gravitational biology, life-support systems, and crew health. The SSF can serve as an experimental vehicle to derive the required knowledge needed to establish a commitment to manned Mars missions and colonization plans.
An evolutionary program of space science missions for the lunar surface and the transportation system concept developed to deploy them are described. Lunar-based science systems will evolve from simple, robotic instruments such as a lunar transit telescope (LTT) to large, observatory-class instruments like a 16-meter optical telescope assembled by astronauts at a lunar base. A transportation system concept to support the Space Exploration Initiative (SEI) and the deployment of these science payloads is described. Beginning with a post-Artemis lander capability, a modular approach to lunar landers is proposed as a way to maximize commonality and to support evolving SEI transportation requirements.
In the Space Exploration Initiative (SEI) mission scenarios, expanding human presence is the primary driver for high data rate Mars-Earth communications. To support an expanding human presence, the data rate requirement will be gradual, following the phased implementation over time of the evolving SEI mission. Similarly, the growth and evolution of the space communications infrastructure to serve this requirement will also be gradual to efficiently exploit the useful life of the installed communications infrastructure and to ensure backward compatibility with long-term users. In work conducted over the past year, a number of alternatives for supporting high data rate Mars-Earth communications have been analyzed with respect to their compatibility with gradual evolution of the space communications infrastructure. The alternatives include RF, millimeter wave (MMW), and optical implementations, and incorporate both surface and space-based relay terminals in the Mars and Earth regions. Each alternative is evaluated with respect to its ability to efficiently meet a projected growth in data rate over time, its technology readiness, and its capability to satisfy the key conditions and constraints imposed by evolutionary transition. As a result of this analysis, a set of attractive alternative communications architectures have been identified and described, and a road map is developed that illustrates the most rational and beneficial evolutionary paths for the communications infrastructure.
The Mars SEIS experiment. The SEIS experiment was first proposed by IPGP (and accepted) for the NetLander mission. It integrates two VBB (Very Broad Band) seismometers, a three axis Short Period seismometer and a series of environmental sensors for pressure, infra-sounds and temperature. IPGP (France) has the overall responsibility of the experiment and is responsible for the seismic and environmental sensors. ETHZ (Switzerland) is responsible for the electronics of the experiment and JPL (USA) for the SP (Short Period) sensors. As NetLander mission has been cancelled (while fortunately the development still goes on), this seismic package can be proposed for future Mars missions.
A panel was organized by NASA/DOE/DOD to study nuclear fuels, materials, and related nuclear propulsion technologies for SEI, and the panel findings are discussed. The fuels/materials requirements for nuclear thermal propulsion and nuclear electric propulsions are reviewed, and the development items such as 'element' development and characterization, fabrication process development, nuclear capsule tests, nuclear loop tests, and nuclear furnace tests are examined for selected classes of fuels.