Stories of modern science ... from UPI

ROBOTS USE OCEAN POWER

The Office of Naval Research is looking at robotic gliders that move through water rather than air. They are underwater vehicles powered by changes in their buoyancy or by different temperature layers in the ocean. Webb Research of East Falmouth, Mass., makes the Slocum Glider, which uses a heat engine that draws energy from the ocean thermocline -- the boundary between the warmer water above and the cooler waters below where temperatures change rapidly. The deep ocean glider can cruise for five years in a vertical zig-zag from the surface to depths of about 5,000 feet, measuring salinity and temperature, plotting currents and eddies, counting microscopic plants and recording biological sounds. The University of Washington Applied Physics Laboratory's Seaglider is powered by buoyancy control and wing lift. It dives and climbs, with a range of 3,500 feet, along slanting glide paths and can cross the ocean basin in missions that last months. Seaglider collects high resolution profiles of physical, chemical and bio-optical ocean properties.

STUDYING MATERIALS IN MESOSCALE RANGE

Researchers at the Oak Ridge National Laboratory have a new tool to study microscopic heterogeneous -- dissimilar -- material structure in greater detail and 3-D -- paving the way for developing uses for new materials. All materials have heterogeneous microstructures and senior researcher Ben Larson's new technique allows scientists to look at materials between one-tenth of a micron to hundreds of microns -- the so-called mesoscale. A micron is equal to 1-millionth of a meter. The tool uses a knife-edge profiler as a moving pinhole camera to make measurements with a charge coupled device area detector. It allows researchers to measure structures in the mesoscale range without destroying the sample.

SPACE TECHNOLOGY FIGHTS CRIME ON EARTH

A new hand-held device may allow police investigators to bypass long waits for laboratory test results and instantly confirm whether a suspect has recently fired a gun. New Scientist reports NASA and the U.S. National Institute of Justice are teaming up to adapt space research to fight crime. Jacob Trombka, a physicist at NASA's Goddard Space Flight Center, says the key is X-ray fluorescence, used by NASA's Near Earth Asteroid Rendezvous probe, which touched down on the asteroid Eros in February 2001. X-ray fluorescence spectrometry can identify chemical elements in a substance by measuring the wavelengths it emits when exposed to X-rays. NEAR's sensors recorded cosmic X-rays bouncing off the asteroid and beamed details back to Earth. Trombka believes a handheld forensic tool could work along similar lines, taking X-ray fluorescence readings at the scene of a crime and beaming them to a computer for instant analysis. Forensics experts could quickly detect traces of blood, semen or gunshot primer on suspects' hands.

ANTARCTIC STREAM SWITCH

It's almost impossible for a river or stream to stop its flow and then reverse course but an ice stream in Antarctica appears to have done just that. Howard Conway, a University of Washington glaciologist who has studied the West Antarctic Ice Sheet, where the stream is located, says it's remarkable. He and colleagues from the California Institute of Technology collected ice core data, images from ice-penetrating radar pulled behind snowmobiles and information from global positioning sensors placed on poles set in the ice. The evidence shows about 250 years ago, Ice Stream C-zero quit flowing at a fast rate, at least 325 feet a year -- fast enough to open crevasses in the ice. It gradually stopped its flow toward Ice Stream C and now flows into the Whillans Ice Stream. That is because Ice Stream C thickened and deflected the flow from Ice Stream C-zero. Fast-flowing streams that rapidly move ice from the interior of the ice sheet to the ocean are one of several ways Antarctica is losing mass. The West Antarctic Ice Sheet -- as large as Texas and Colorado combined -- has shrunk substantially in the past 7,500 years.

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(EDITORS: For more information about GLIDERS, contact John Petrik at 703-696-5034 or e-mail petrikJ@onr.navy.mil. For MATERIALS, Ron Walli, 865-576-0226 at wallira@ornl.gov, for XFS, contact Michelle Soucy at New Scientist, 617-558-4939 or michelle.soucy@newscientist.com, and for ANTARCTIC, Vince Stricherz at 206-543-2580 or vinces@u.washington.edu)