Magazine

The Spectral Analysis Tool (SAT) computer program assists in analysis of interference between radio signals in Earth/spacecraft communications. SAT provides an easy-to-use interactive graphical interface with a menu for selecting among the following utility subprograms: an editor for...

Several algorithms developed for use in automated planning and scheduling of sets of interdependent activities employ aggregation techniques to increase the efficiency of searching for temporal assignments that are legal in the sense that they do not violate constraints. In the aggregate-search...

The work considers passive dynamic stability of sail craft, propelled by microwave beams. Such systems are under consideration as low-cost means of interstellar travel. Sail-craft shapes offering passive dynamic (neutral) stability are identified. Passive stability is a key mission-enabling attribute. Very...

A report proposes ultralight balloon systems to carry a 10-kg payload, including scientific instruments for exploring the atmospheres of Uranus and Neptune. The system masses to be transported to those planets would be kept low by not transporting balloon-inflating gases. Each system...

A report discusses the adaptation of foaming-in-place techniques and materials to outer-space applications. Foaming in place is used commercially in terrestrial sealing, insulating, bonding, and retrofitting applications. The room-temperature outer-space versions of foaming in place are expected...

A document in the form of lecture slides outlines a program of development of capabilities for acquisition of signals, tracking of signal sources, and pointing of transmitters and receivers in deep-space optical communications. Topics addressed on the first few slides include the...

The SAR Processing System Raw Data Processor (SPS RDS) computer program is used in the Alaska SAR Facility (ASF) to scan and decode raw data that have been downlinked from the European Remote Sensing Satellite (ERS), the Japanese Earth Resources Satellite (JERS), and the RADARSAT (a Canadian...

The Object Oriented Data Technology group at NASA's Jet Propulsion Laboratory is developing software for locating data — especially scientific data — stored in various formats on heterogeneous computer systems at different locations. The software is intended to exploit and extend...

The term "microGPS" denotes a Global Positioning System (GPS) receiver design concept that combines relatively simple, lightweight, low-power-consumption hardware with portable, efficient software. The power demand of a microGPS receiver can be made low because it is designed to sample sparsely; that is, to...

The Spacecraft Control Toolbox (SCT) helps design control systems and attitude estimators, analyze station-keeping requirements, generate fuel and pointing budgets, and analyze spacecraft dynamics. The SCT provides a comprehensive set of over five hundred functions including:

The RecDel System is a low-cost software application that helps different groups of a complex project negotiate interfaces between interdependent schedules. The RecDel system is based on a concept of distributed planning, wherein the cognizant persons retain control over, and responsibility for, their...

A software package for use in a ground receiving station detects a beacon-monitor tone transmitted by a spacecraft. To recapitulate from previous NASA Tech Briefs articles on beacon monitoring: An onboard computer processes data from onboard sensors to summarize the condition of the spacecraft in...

The Automated Real-Time Spacecraft Navigation (ARTSN) system is a prototype of a class of software systems for automated navigation and monitoring of spacecraft from stations on the Earth. The system processes radio metric tracking data (principally, range and Doppler measurements) in real time to...