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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: Amber Jones Contents of this News Tip:
Astronomers Top Distance Records for Observations of Celestial ObjectsAstronomers of the Sloan Digital Sky Survey have found the most distant object ever identified: a quasar that resembles a bright red star. The distinctive colors in the quasar's spectrum reveal that it dates from a time when the universe was less than a billion years old. The recently announced finding by the National Science Foundation (NSF)-supported team continues a spate of recent records. Each new observation of distant objects adds to scientific knowledge about the early structure of the universe. The quasar showed up in observations taken in March 2000 with ground-based telescopes. With a redshift of 5.8, its distance from Earth surpasses that of a galaxy with a redshift of 5.7 discovered last year. Redshift, or the amount that light from a distant object shifts toward the red end of the electromagnetic spectrum by the time it reaches Earth, is used as a measure of distance to celestial objects. Earlier this year, a team of NSF-supported astronomers found the most distant quasar identified to that time, with a redshift of 5.5; and, two Sloan Digital Sky Survey astronomers dicscovered a quasar with a redshift of 5.3. Astronomers have only recently identified objects with redshifts greater than about 5.0. The latest discoveries, with more than twice that redshift, allow scientists to "look back" in time to study the universe when it was less than two billion years old -- billions of years before the sun and earth were formed. [Amber Jones] Innovative Student-Designed Bridge Will Test Carbon Fiber ConstructionStudents supported by NSF have developed a new type of highway bridge that will be tested this year in Michigan's harsh climate. About 40 percent of U.S. highway bridges are structurally or functionally deficient, mainly because the traditional steel and concrete construction materials are vulnerable to corrosion. Twelve undergraduates at Lawrence Technological University in Southfield, Mich., researched and designed a bridge system that uses concrete prestressed with a carbon-fiber-reinforced polymer (CFRP). The concept could potentially double the life span of highway bridges. Carbon fiber composites are stronger and lighter than steel. Developed for the aerospace industry, CFRP is used in sports equipment and race cars. Though it has been employed in bridges in Japan, Europe and Canada, this will be the first such use in the United States. The project will comprise two parallel bridges over the Rouge River in Southfield, a suburb of Detroit. Building one conventional steel-concrete structure and one that uses the composite reinforcement and the students' design will allow the university to compare their performance. [Amber Jones] Land Use Affects Carbon Storage More Than Atmospheric Carbon Dioxide or ClimateA new study has found that land use, far more than atmospheric carbon dioxide levels or the vagaries of climate, influences how much carbon is stored by ecosystems in the continental United States. Previous estimates of annual U.S. carbon storage may have overstated the levels, say researchers at the NSF-supported National Center for Atmospheric Research in Boulder, Colo. Scientists have been searching for a carbon storage mechanism, or sink, to explain why atmospheric carbon dioxide (CO2) levels remain lower than expected as emissions rise. The carbon mystery is key to understanding the impact of humans on Earth's climate. Atmospheric CO2 stimulates photosynthesis in plants, increasing forest uptake of carbon. A more dramatic influence on carbon storage is climate: wildfires, volcanic eruptions, drought and El Nino episodes can alter terrestrial carbon storage by as much as 100 percent in a given year. Now scientists have found that, during 1980-1993, CO2 fertilization and climate effects accounted for only 100 million tons per year--about one-third--of the estimated carbon stored in the U.S. land sink. The remaining 200 million tons, or two-thirds, of the stored carbon resulted from the regrowth of abandoned agricultural lands and forests harvested before 1980. "To predict and plan for future climate change, we need to fully understand the amount of carbon being stored both in the United States and globally, and what controls that storage," explains NCAR scientist David Schimel. The study was supported by NSF, the U.S. Forest Service, NASA and the Electric Power Research Institute. [Cheryl Dybas]
**NSF is an independent federal agency which supports fundamental research and education across all fields of science and engineering, with an annual budget of about $4 billion. NSF funds reach all 50 states, through grants to about 1,600 universities and institutions nationwide. Each year, NSF receives about 30,000 competitive requests for funding, and makes about 10,000 new funding awards. For instant information about NSF, sign up for the Custom News Service.
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