Mission risk appraisal.
Mission risk appraisal technique for identification and quantification of high risk areas for unmanned interplanetary missions
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Mission risk appraisal technique for identification and quantification of high risk areas for unmanned interplanetary missions
Steepest descent method of trajectory optimization for computing lunar and interplanetary transfer missions, noting terminal constraints
Mariner IV flight magnetometer data, determining interplanetary field and geomagnetic variability relationship
Need for manned spacecraft on & around moon, in interplanetary space, & on planets
Flight of Venus 4 including systems analysis, planetary landing, and scientific data
NASA aeronautics and space research including near-Earth, cislunar and interplanetary space, manned flights, meteorology and communications
Advanced computer, radiation, and inertial subsystem guidance and navigation requirements of interplanetary manned space flight missions
Pioneer spacecraft flight missions, discussing interplanetary, solar-earth and deep space observations
The paper gives a general description of a continuous/discrete simulator of the telemetry flow from an unmanned interplanetary spacecraft in flight. The real time simulation method is based on the trigger method, where a trigger is a set of control words which describe a condition and an action to be taken upon satisfaction of the condition. Simulation consists of finding the points at which the given condition is satisfied and taking the specified action. The paper describes the four kinds of triggers and how they are called. The calculational algorithm used to advance time in the simulator is briefly described.
A test program aimed at the re-qualification of the 0.2-lbf attitude control thruster of the Voyager 2 spacecraft was carried out while the spacecraft was in flight on an interplanetary trajectory to Uranus. The objective of the program was to determine if the 0.2-lbf thruster could be successfully and repeatedly fired at pulse widths of less than the standard minimum pulse width of 10 milliseconds with no degradation. It was demonstrated that the thruster was qualified for short pulse operation at pulse widths of 4 ms or greater. Pulse widths of 4.0 ms provide an impulse bit of approximately 45 percent of the impulse provided by a 10-ms pulse, and the pulse-to-pulse and unit-to-unit variation is approximately plus or minus 10 percent.
The two biggest challenges to successful human operations in interplanetary space are flight dynamics, constrained by the cold hard physics of the rocket equation, and bioastronautics, the psychophysiological realities of human adaptation, or lack thereof, to the deep space environment. Without substantial innovation in project/mission architecture and vehicle design, human exploration of the Mars system could be problematic for decades. Although a human landing on Mars is inevitable, humans-in-the-loop telerobotic exploration from the outer Martian moon Deimos is the best way to begin. Precursor robotic missions for reconnaissance and local site preparation will be required.
TIGRAS 2.0 is a computer program designed to satisfy a need for improved means for analyzing the tracking demands of interplanetary space-flight missions upon the set of ground antenna resources of the Deep Space Network (DSN) and for allocating those resources. Written in Microsoft Visual C++, TIGRAS 2.0 provides a single rich graphical analysis environment for use by diverse DSN personnel, by connecting to various data sources (relational databases or files) based on the stages of the analyses being performed. Notable among the algorithms implemented by TIGRAS 2.0 are a DSN antenna-load-forecasting algorithm and a conflict-aware DSN schedule-generating algorithm. Computers running TIGRAS 2.0 can also be connected using SOAP/XML to a Web services server that provides analysis services via the World Wide Web. TIGRAS 2.0 supports multiple windows and multiple panes in each window for users to view and use information, all in the same environment, to eliminate repeated switching among various application programs and Web pages. TIGRAS 2.0 enables the use of multiple windows for various requirements, trajectory-based time intervals during which spacecraft are viewable, ground resources, forecasts, and schedules. Each window includes a time navigation pane, a selection pane, a graphical display pane, a list pane, and a statistics pane.
The development of the Ares V launch vehicle will provide levels of performance unseen since the days of Apollo. This capability, like the Saturn V before it, is being developed primarily for crewed lunar missions. However, the tremendous jump in performance offered by the Ares V launch system has tremendous potential for the furtherance of robotic solar system exploration missions as well. Preliminary performance assessments indicate that Ares V could deliver 5 times the payload to Mars as compared to the most capable US expendable launch vehicle available today. Beyond Mars, the outer planets offer a number of high-priority investigations with compelling science. Presently, missions to these destinations are only achievable using indirect flights with gravity assist trajectories and, in many cases, suffer from long flight times. An Ares V with an upper stage could capture these missions using direct flights with shorter interplanetary transfer times that would enable extensive in situ investigations and possibly the return of samples to Earth. This paper lays out an estimate of Ares V performance for moderate and high C3 missions, and goes on to discuss a range of revolutionary mission concepts that could be enabled by this significant in-crease in launch capability.
Computer programs for simulating booster nominal trajectories for interplanetary missions
Power supply and telemetry systems data for IMP III-Explorer XXVIII
The studies reported herein were prepared by Lockheed Missiles & Space Company for the George C. Marshall Space Flight Center, Huntsville, Ala., under Contract No. NAS 8-5024. The results of the Early Manned Interplanetary Mission Study are reported in two volumes. Volume 1 contains the unclassified portion of the studies and Volume 2 presents the classified (CRD) studies relating to orbital escape propulsion systems.
Optimum interplanetary rendezvous with power limited vehicles