|
NSF PR 95-78 - November 22, 1995
Media contact: |
Lynn Simarski |
(703) 306-1070 |
This material is available primarily for archival purposes. Telephone
numbers or other contact information may be out of date; please see current
contact information at media
contacts.
Current Antarctic Research Targets the Sun, Melting
Ice, and Dinosaurs
A giant balloon will circle Antarctica carrying a telescope
trained on the sun, geologists will seek dinosaur
remains entombed in Antarctic rocks, and scientists
on snowmobiles will search for a prime site to drill
a deep ice core to unlock West Antarctica's climate
history. These studies are among the 136 U.S. science
projects now underway during the 1995-96 Antarctic
research season, supported by the National Science
Foundation (NSF), and based mainly out of three research
stations during Antarctica's summer, from October
through February.
Almost three-quarters of the research program -- spanning
astronomy and astrophysics, earth science, glaciology,
oceanography, atmospheric science, and biology --
is supported out of McMurdo Station, located at sea
level on Ross Island, and at Amundsen-Scott South
Pole Station, high up on the ice cap. Another quarter
of the research is conducted from Palmer Station on
the Antarctic Peninsula and on two research vessels.
Antarctic research highlights this season:
Flare Genesis Probes the Sun
In December or January, one of the world's largest
solar telescopes will be lofted into the Antarctic
sky beneath a huge balloon, which will circle the
continent in a steady wind pattern. With 24-hour daylight,
the telescope will be able to peer at the sun nonstop
-- imaging sunspots with unprecedented resolution,
and mapping associated magnetic fields believed to
cause solar flares. The research team led by David
Rust of Johns Hopkins University aims to understand
how magnetic fields at the sun's surface emerge, coalesce,
unravel, and finally blow up as solar flares. They
hope the work will lead to reliable forecasts of both
solar activity as well as the arrival of shock waves
and atomic particles from the sun. Excellent quality
images are expected to be available shortly after
the flight.
Neutrino Visions in Antarctic Ice
Drilling resumes at the South Pole to complete AMANDA,
the largest neutrino detector on earth and part of
the vanguard in the new field of neutrino astronomy.
The Antarctic Muon and Neutrino Detector Array is
looking for high-energy neutrinos sub-atomic particles
that are spawned by supernovae, pulsars, neutron stars,
or other sources beyond our galaxy, with the aim to
one day map such neutrino sources in space. AMANDA,
a joint enterprise of the University of Wisconsin,
the University of California (Berkeley and Irvine),
the University of Stockholm, the University of Upsala,
and the German Electron Synchrotron (DESY), has already
been watching the sky for supernovae since early this
year. As construction of the array continues, a hot
water drill will plumb the ice; then, photomultiplier
tubes, like beads on a string, will be lowered one-to-two
kilometers down into the holes, which will close up
as the water refreezes. Six new strings are being
added this year to the four already installed. The
ice at the South Pole has proven to have singular
clarity for detecting the bluish flashes of light
- Cherenkov radiation -that tell of a neutrino collision.
Hot Vents in Polar Seas
Researchers aboard NSF's icebreaking research vessel,
the Nathaniel B. Palmer, have just completed a survey
of the complex ocean bottom in the Bransfield Strait
at the northern end of the Antarctic Peninsula. Geophysicists
Lawrence Lawver of University of Texas-Austin, and
Gary Klinkhammer, Oregon State University, have explored
a unique region where continental crust is rifting
apart, perhaps like the Gulf of California opened
in its earlier stages of evolution. Hydrothermal vents
have been found near this rift, where plumes of hot
water with dissolved minerals are spewing forth, possibly
from natural smokestacks called "black smokers." The
study will add to knowledge of volcanic processes
and mineral formation in a rift zone. Unusual communities
of deep-sea life, known to inhabit hot vents, could
also live here, but have not yet been found at these
high polar latitudes. (For cruise reports, see: WWW.IG.UTEXAS.EDU/NEWS/BRANSFIELD/INDEX.HTML.)
A Hunt for Dinosaurs
In the Transantarctic Mountains, a team headed by Augustana
College geologist William Hammer will survey remote
mountaintops protruding from the ice sheet for fossils
of mammals and reptiles, including dinosaurs. In much
of the continent, fossils and rocks are concealed
beneath ice that can be miles thick. Exposed rocks
in the study area near the Shackleton Glacier, however,
offer excellent prospects to yield animal remains
from the middle Triassic to the lower Jurassic, similar
to the dinosaurs and other fossils recovered in the
past near the Beardmore Glacier. The vertebrate fossils
offer insight on how these animals evolved at high
latitudes and what climates were like when they lived.
Counting Tree Rings in Antarctica's Fossil Forests
The Shackleton Glacier region harbors abundant plant
fossils, including remains of ancient forests, mineralized
peat deposits, and pollen. A team headed by paleobotanist
Edith Taylor, University of Kansas, will collect and
describe in detail this ancient flora, helping to
reconstruct what the Antarctic was like during Permian
and Triassic times about 200280 million years ago.
Also based at this season's Shackleton camp, a special
field base for research coordinated by Ohio State
University geologist David Elliott, other geologists
will be seeking to fill in the picture of how past
environments and life evolved in Antarctica. Until
the late Mesozoic, about 100 million years ago, Antarctica
sat at the center of the supercontinent of Gondwanaland
-- a history these studies will flesh out.
West Antarctic Ice: Stable or Not?
West Antarctica's ice cover, drained in part by dynamic,
fast-moving ice streams flowing into the Ross Sea,
is the largest ice sheet on earth resting well below
sea level. The history of the ice, and its potential
for future "collapse," or rapid disintegration, continues
as the focus of a multi-year, multidisciplinary research
effort. In places, the ice sheet shows rapid and dramatic
changes that could portend a rapid rise in sea level
across the globe -- or may not. Geophysicists Donald
Blankenship, University of Texas Austin, Robin Bell,
Lamont-Doherty Earth Observatory, and Carol Finn,
U.S. Geological Survey, spearhead an effort to fly
an aircraft filled with geophysical instruments over
the ice streams. They will use the data to model ice
sheet behavior, as will a University of Wisconsin
group. Down on the ice surface, a traverse team headed
by University of New Hampshire glaciologist Paul Mayewski
is extracting ice cores and examining them for clues
to climates past -- ultimately looking for the best
site for a deep ice core.
Tiny Extraterrestrials at the South Pole?
Antarctica's ice is a famous storehouse for meteorites,
ranging from large to microscopic. A team led by Susan
Taylor of the Cold Regions Research and Engineering
Laboratory plans to begin collecting millions of micrometeorites
from the new well that provides water for South Pole
Station, a project that will last five years. As the
ice melts in the well, meteorites are postulated to
concentrate at the bottom of the hollow, promising
what may be the richest and best-dated source of dust
from space.
An Antarctic Lake at First Light
After the long Antarctic winter gives way to the earliest
rays of the sun, life in the unique, permanently frozen
lakes of Antarctica's Dry Valleys begins to unlimber.
This August, a team led by Montana State University
biologist John Priscu travelled to the lakes to watch
photosynthesis begin, the initial step in understanding
the dynamics of microbe assemblages (cyanobacteria
and eubacteria) living in the ice of at least seven
Dry Valley lakes. The study will help illuminate the
dynamics of carbon and nitrogen in the valleys, and
complement existing studies of microbial communities
in sea ice. Such life in Antarctica may be analogous
to Mars, which is thought to have had liquid water
in the past. Microbial life may still linger in the
ice and rocks on that planet.
Note to reporters: For a photo of William Zinsmeister
holding an Antarctic fossil, call Purdue University
News Office at (317) 494-2096.
|
|