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For more information on these science news and feature story tips, please contact the public information officer at the end of each item at (703) 292-8070. Editor: Peter West Contents of this News Tip:
An Icy End to the Universe? Shapes of Galaxies May Lend More EvidenceScientists have long debated whether the universe is headed for a fiery finish or an icy end. Now one group of researchers supported by the National Science Foundation (NSF) believes that its analysis of the shapes of nearby galaxies favors the theory of a cold demise. A team led by Adrian Melott, a University of Kansas cosmologist, studied the shapes of 180 galaxy clusters containing galaxies numbering from the hundreds to the thousands. The team found that while nearby galaxy clusters were fairly spherical, the farthest clusters were more squashed and irregular. The team reported its findings in the October 1 Astrophysical Journal Letters. The light from the faraway galaxies began its journey toward Earth early in the development of the universe, and therefore presents a snapshot of the universe as it was long ago. The shapes of those clusters led the researchers to believe that galaxy clusters have been evolving toward a more regular, spherical shape. This is an indicator of a low-density universe, in which the expansion is outrunning the clumping effect of gravity. The clusters are becoming more spherical because they are less often deformed by new matter falling into them. As the gases and other materials that make up the universe spread out even further, the researchers say the universe could become a cold, empty place. [Amber Jones] Safely Storing Hydrogen: New Nanoscale Sensor Could Help Boost Alternative Energy SourceNSF-supported researchers have fabricated a minute sensor for detecting hydrogen gas leaks that could make storing the explosive substance a safer proposition, thereby aiding in the development of the gas as an alternative energy source. Hydrogen combustion is a potentially attractive method of producing energy because it produces only water as a by-product. But hydrogen -- like gasoline -- is potentially explosive. This complicates storage, particularly in confined areas such as a tank in a hydrogen-powered vehicle. As greater use is made of this clean-burning fuel for basic energy needs, the development of reliable, inexpensive sensors will be more important for detecting leaks. Analytical chemist Reginald Penner and colleagues from the University of California at Irvine and Montpellier University in France report that their ultra-small device, made from nanoscale arrays of palladium wires, responds to leaks an order of magnitude faster than conventional sensors. In the presence of hydrogen, the resistance of the array decreases rapidly, apparently due to the closing of nano-sized gaps in the wires as the palladium absorbs the gas. In the absence of hydrogen, the circuits reopen. Besides being reliable, reusable, small and unobtrusive, the device operates on only a few nanowatts of power. Penner’s team reported its findings in the September 21 issue of Science. [Amber Jones] Earthquake Engineering: Team Plans for Cyber Network's OperationNSF has selected a consortium of universities to establish the new organization that will manage an NSF-funded network of earthquake engineering research facilities, named the George E. Brown, Jr. Network for Earthquake Engineering Simulation (NEES), slated to start operation in 2004. The Consortium of Universities for Research in Earthquake Engineering (CUREE) of Richmond, Calif., will involve the broad earthquake engineering community in establishing the entity that will manage NEES during its first decade. NEES will allow researchers to share and remotely operate experimental equipment at advanced earthquake engineering facilities and to more easily share data and computations. The equipment -- including shake tables, a tsunami wave basin, geotechnical centrifuges and laboratory, and mobile geotechnical and structural experimental capabilities -- models and analyzes earthquake forces and helps engineers design buildings, bridges and other infrastructure to withstand those forces. While the management project is under way, the information technology network called NEESgrid is being designed and implemented by a team led by the University of Illinois at Urbana Champaign. [Amber Jones] For more information, see: http://www.eng.nsf.gov/nees
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