December 3, 1999
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: Cheryl Dybas
Contents of this News Tip:
A team of astrophysicists supported by the National Science Foundation
(NSF) spotted 20 supernovae this November, partly due to a student’s
hard work.
Alicia Soderberg, a physics and math major at Bates College in Maine,
joined the team for its recent search as part of an NSF program that provides
undergraduates with hands-on research experience. Using the prominent
Canada-France-Hawaii Telescope in Hawaii, she personally identified nine
of the 20 new supernovae, including the most distant one found to date.
"It’s thrilling to shout across the room 'I’ve got one!' when you spot
the first supernova during an observing run," says Soderberg. "No classroom
experience could have prepared me for the excitement of doing hands-on
astronomy with some of the world’s best."
The team launched its search for supernovae -- bright, dying stars located
billions of light years from Earth -- in the hope that measuring the light
from these stars can help determine the change in the rate of expansion
of the universe. Preliminary results imply that the universe is accelerating,
not slowing down. NSF’s Cerro Tololo InterAmerican Observatory in Chile
has also been used in the search. [Amber Jones]
For more information, see: http://www-cfa.harvard.edu/cfa/oir/Research/supernova/HighZ.html
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One of the most perplexing segments of the global mid-ocean ridge spreading
system is currently being investigated by researchers aboard the scientific
drillship JOIDES Resolution. The scientists hope to determine the ridge
segment's mantle history. The segment is located south of Australia near
where the Pacific and Indian Oceans meet, in a region known to mariners
as the "Roaring 40s" for the extreme and dangerous sea conditions at
this latitude. The research is being conducted under the aegis of the
international Ocean Drilling Program (ODP), and is funded in large part
by the National Science Foundation.
Spreading centers are unique locations on Earth where new ocean floor
(crust) is continuously formed, explains David Christie of Oregon State
University, co-chief scientist of the expedition. Typically, spreading
centers rise above the surrounding seafloor to form continuous ridges.
But the seafloor in the current study area changes dramatically over short
distances, from smooth surfaces to very rough terrain. Geologists aboard
the JOIDES Resolution believe that this change in seafloor terrain represents
a boundary that has formed from converging pools of magma, molten material
located deep in the Earth at the lower mantle. This narrow boundary, dubbed
the Australian-Antarctic Discordance, stretches along the ridge axis between
Australia and Antarctica.
The shipboard science team hopes to determine the mantle migration history
beneath the Pacific Plate, one of Earth's tectonic plates, over the past
30 million years, explains Bruce Malfait, director of ODP at NSF. Because
lavas that erupted from Indian Ocean spreading centers are chemically
distinct from those of the Pacific Ocean, scientists can "fingerprint" the
origin of the rocks drilled and sampled to better understand this unusual
boundary between Pacific and Indian Ocean mantle. [Cheryl Dybas]
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Speaking to a group of teachers in West Virginia last month, NSF director
Rita Colwell connected education quality to economic growth as the nation
moves into an economy based on knowledge and ideas. Teacher training
and development are more important than ever, and NSF is "thinking big" in
this area, she said.
"A 21st century workforce must be taught and trained by teachers with
21st century skills. Anything less inhibits the nation’s ability to compete
and prosper. Anything less imperils our children and their children," said
Colwell. NSF’s teacher training programs, including the new graduate teaching
fellows, reach more than 95,000 future teachers each year, she said. This
will help address the estimated need -- based on NSF and Department of
Education projections -- for more than 200,000 math and science teachers
by the year 2006. [Mary Hanson]
For Colwell speeches on-line, see: http://www.nsf.gov/od/lpa/forum/colwell/start.htm Top of Page
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