Physical Sciences

Physical Causes of Extremely Low Geomagnetic Activity

NASA’s Jet Propulsion Laboratory, Pasadena, California An analysis of solar, solar wind, and geomagnetic data during the recent solar cycle minimum (2008) has recently been undertaken. It was discovered that the lowest value of the Ap index [this index is an averaged planetary A index based on data from a set of specific magnetometer stations] in the history of its recording occurred during 2009, about 1 year after solar minimum. The investigators were able to determine that it was the decrease of solar and interplanetary forcing that was causing the anomalous effect. The coronal holes, which emit high-speed solar wind plasma streams, were located at middle (solar) latitudes during this epoch of the solar cycle. Thus the full brunt of the solar wind and its embedded Alfvén waves missed the Earth and its magnetosphere, lessening the effect of the solar wind-magnetosphere interaction.

Posted in: Physical Sciences, Briefs

Read More >>

Green PCB Removal From Sediment Systems (GPRSS)

A redeployable polymer blanket attacks and adsorbs PCBs. John F. Kennedy Space Center, Florida A number of NASA centers have used polychlorinated biphenyl (PCB)-containing materials that have subsequently ended up in surrounding sediment systems. Each center is evaluating remediation technologies that may have application to their environmental problems; however, there are only limited options available for application to sediments containing PCBs. Currently, the most utilized option is dredging followed by disposal in a Toxic Substances Control Act (TSCA)-regulated landfill. This is an expensive option with long-term liability implications for simply enacting a waste transfer remedy (as opposed to a waste destruction alternative), as well as possible contaminant re-introduction into the water table. PCB contamination in sediment systems is a global issue, posing ecological and human health risks.

Posted in: Physical Sciences, Briefs

Read More >>

Internalization of Non-Spherical Particles

This device enhances proliferation of cell cultures in a rotating bioreactor. Lyndon B. Johnson Space Center, Houston, Texas This invention specifically relates to an interchangeable sleeve that encompasses a rotating, substantially cylindrical bioreactor. The sleeve supplies a time-varying electromagnetic force of from 0.05 to 0.5 gauss to the culture chamber of the bioreactor in order to increase cell growth and proliferation within the rotating bioreactor. The sleeve comprises a substantially cylindrical and rigid, electrically conductive material wound in a cylindrical shape, and is capable of being connected to a pulsating, time-varying electromagnetic current.

Posted in: Physical Sciences, Briefs

Read More >>

System for Observing Dynamic Atmospheric Phenomena

System has drastically increased transmitter capability at much reduced cost. NASA’s Jet Propulsion Laboratory, Pasadena, California Existing observing systems are inadequate to measure a variety of dynamic atmospheric processes. Ground-based or airborne systems do not observe over sufficiently large regions to capture the context or time history of many phenomena. Space-based systems do not observe a specific region over sufficient duration with sufficient spatial resolution to capture the essential features of the phenomena. Radar systems are limited in what they can observe because of the need for scattering sources to be present in the observed volume.

Posted in: Physical Sciences, Briefs

Read More >>

Covariance Analysis of Astrometric Alignment Estimation Architectures for Precision Dual-Spacecraft Formation Flying

A paper highlights analysis of proposed navigation systems and architectures for achieving precise dual-spacecraft astrometric alignment. The dynamics of dual-spacecraft relative motion, within a restricted n-body problem framework, are shown to reduce to a simple linear form for use in estimation filter design and error analysis for a deep space mission application, such as MASSIM (Milli-Arc-Second Structure Imager). This model is augmented with simplified measurement process models of relevant measurement types. These include inertial sensors, such as accelerometers and rate gyros, as well as optical alignment sensors, such as star and laser beacon trackers. A consider-state covariance analysis tool is developed from these process models and used to study the performance of proposed estimation architectures for the MASSIM application. This work develops a generic analysis methodology for evaluation of dual-spacecraft relative navigation systems and architectures for precise dual-spacecraft astrometric alignment.

Posted in: Physical Sciences, Briefs, TSP

Read More >>

Automated Purgatoid Identification

An algorithm was developed that automatically processes images captured by the HiRISE camera on the Mars Reconnaissance Orbiter to identify and locate the presence of purgatoids in monochrome images.

Posted in: Physical Sciences, Briefs, TSP

Read More >>

Interplanetary CubeSats

A report describes upgraded CubeSat satellite elements for the interplanetary environment, with solar sail propulsion and the interplanetary superhighway for navigation and maneuvering. They can host small, capable instruments and optical telecommunications on a mission to map the composition of a sequence of near-Earth asteroids and planetary bodies.

Posted in: Physical Sciences, Briefs, TSP

Read More >>

White Papers

Spectrum Analyzer Fundamentals - Theory and Operation of Modern Spectrum Analyzers
Sponsored by Rohde and Schwarz A and D
Eliminate Risk of Contention and Data Corruption in RS-485 Communications
Sponsored by Sealevel
Managing Risk in Medical Connectors
Sponsored by Fischer Connectors
T&M Solutions for Software Defined Radios (SDR)
Sponsored by Rohde and Schwarz A and D
Learn LED Test Techniques
Sponsored by Keithley
Bearing selection for low-speed applications
Sponsored by Kaydon

White Papers Sponsored By: