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NASA selects radiation belt mission candidate for further study

An instrument developed by Los Alamos National Laboratory (LANL) and SwRI is part of a proposal selected as a candidate to study the Earth’s space weather from a pair of orbiting satellites.

Radiation Belt Storm Probes (RBSP) will examine how the Earth’s radiation belts form and change during space storms caused by solar activity. This type of radiation is hazardous to astronauts, orbiting satellites and aircraft flying high-altitude polar routes. Each team will receive $1 million to perform a study focused on cost, management and technical feasibility. NASA will then select one of the teams for full development of the payload.

SwRI and LANL are developing the Helium, Oxygen, Proton and Electron (HOPE) spectrometer for the Radiation Belt Storm Probes — Energetic particle, Composition, and Thermal plasma

(RBSP-ECT) mission study, led by Boston University. SwRI will build the electronics unit and microprocessor, write the operating software and develop the spacecraft interfaces. LANL, which leads the HOPE investigation, will build and calibrate the sensor. Plans call for a total of three instruments to be delivered to NASA.

HOPE is designed to measure the ions and electrons that exist in the Earth’s plasmasphere, plasma sheet and ring current, including the relative composition of the most important components — hydrogen, helium and oxygen ions — from 1 to 50,000 electron volts. In addition to being source material for the radiation belts, ions play an important role in accelerating plasma to radiation belt energies of many million electron volts.

“They do this by generating plasma waves that can ‘surf’ other particles to very high energies through resonant interactions,” said Dr. David T. Young, lead co-investigator of the instrument and an Institute scientist in the SwRI Space Science and Engineering Division. “Even after all these years, scientists still don’t know how the radiation belts form and how they respond to space weather coming from the sun. This mission will help increase our understanding of these unknown processes.”

Space weather storms involve constantly changing magnetic and electric fields and gusts of radiation that produce intense currents in the Earth’s ionosphere. These can black out long-distance communications over entire continents and disrupt the global navigational system.

Prof. Harlan Spence of Boston University leads the RBSP-ECT team and Dr. Geoff Reeves of LANL leads HOPE. The other teams funded for the phase A study are led by the University of Iowa at Iowa City, the University of Minnesota at Minneapolis and the New Jersey Institute of Technology at Newark.

The two-spacecraft Radiation Belt Solar Probe mission is scheduled for launch in 2012. The mission is part of NASA’s Living with a Star Program, designed to gain understanding of how and why the sun varies, how planetary systems respond to the sun, and solar effects on human space and Earth activities. NASA’s Goddard Space Flight Center manages the program for the Science Mission Directorate.

New “super cell” evaluates heavy-duty engines

SwRI has developed a “super cell” to evaluate the effects of altitude and other environmental conditions on performance and pollutant emissions of heavy-duty engines, with interactions of fuels, lubricants and catalysts.

“Regulatory groups worldwide are concerned that pollutant limits demonstrated in currently prescribed test procedures may be exceeded in day-to-day, real-world applications,” said Terry L. Ullman, assistant director of the SwRI Engine and Emissions Research Department. The Environmental Protection Agency bolstered assurance that emissions levels are held in check by introducing not-to-exceed (NTE) emission limits that apply to in-use operation over a range of environmental conditions encountered by trucks and other engine applications.

Conditions within not-to-exceed compliance zones are readily available with the super cell, which applies various altitude conditions, in combination with a range of temperatures and humidity levels, to engines of 100–750 horsepower.

“Although these conditions can be assessed to some degree in the field, engine development and calibration efforts are better performed and validated under tightly controlled conditions,” said Ullman. “By combining the environmental conditions seen throughout the world into an engine test cell, we can help manufacturers and suppliers meet the challenges of more stringent emission limits for hydrocarbons, carbon monoxide, oxides of nitrogen and particulates.”

Although the super cell is designed to ensure NTE compliance, it also can be used to optimize engines for fuel economy and performance at conditions not easily achieved in the laboratory. Combining this capability with precise instrumentation and engine operation, SwRI helps manufacturers evaluate and optimize how their engines, fuels and lubricants will operate at high altitudes, such as those in Denver and Mexico City, as well as at lower altitudes. Devices that control emissions or improve performance can also be quantified.

The ability to evaluate engines at high and low altitudes using a consistent set of instruments, with the same engine setup and control, at the same location, also relieves concerns about lab-to-lab variability. The super cell uses a full-flow, constant-volume sampling, gaseous emissions bench and particulate measurement system to provide emissions data compliant with current and 2007+ highway engine regulations, as well as current and future non-road engine regulations. The system can accommodate steady-state and transient engine operation at altitudes up to 12,000 feet above sea level, along with additional variations in temperature and humidity conditions to investigate emissions levels and engine performance for markets outside the NTE envelope.

Contact Daniel Stewart at (210) 522-3657 or daniel.stewart@swri.org.

Popular Science names SwRI space physicist one of “Brilliant 10” young scientists

Dr. Jerry Goldstein, a principal scientist in SwRI’s Space Science and Engineering Division, has been named one of the “Brilliant 10” young scientists to watch. The group of 10 researchers is profiled in the October issue of Popular Science.

Goldstein, 35, is a space physicist specializing in the structure and dynamics of the Earth’s plasmasphere. His research has revealed the broader, more far-reaching significance of events in this region, which produces some of the strongest space weather phenomena affecting life on Earth. For example, space storms strip away the outer layers of the plasmasphere, producing tremendous plumes of plasma that extend up to 60,000 kilometers into space. These plumes interfere with the transmission of signals from global positioning system (GPS) satellites, producing large (up to 80 meters) errors in GPS-based navigation. These errors affect a wide range of GPS users, including civilian and military aircraft, vessels at sea, automobiles and surveyors. Goldstein’s work in explaining, and ultimately predicting, the occurrence of plasma plumes promises to lead to future prediction and mitigation techniques for these GPS disruptions.

“Jerry’s research has enabled rapid progress in a field that had been progressing only very slowly over the past 30 years,” said Dr. Jim Burch, vice president of the SwRI Space Science and Engineering Division. “His studies on the Earth’s plasmasphere, as well as the electric fields of the inner magnetosphere that control it, clearly establish him as the leading authority in this field.”

Goldstein is the 2006 recipient of the Macelwane Medal, conferred by the American Geophysical Union (AGU) in recognition of his plasma-spheric research. He is active in public outreach and education, serving as an adjoint assistant professor at The University of Texas at San Antonio. He is also increasingly called on by the media to comment on space weather phenomena and the impact of space radiation on commercial airline passengers.

SwRI researchers Dr. James D. Walker, an impact physicist, and Dr. Robin M. Canup, a space scientist, were also named to the “Brilliant 10” list in 2004.

Contact Goldstein at (210) 522-5633 or jerry.goldstein@swri.org.

Published in the Fall 2006 issue of Technology Today®, published by Southwest Research Institute. For more information, contact Joe Fohn.

Fall 2006 Technology Today
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