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The National Science Foundation (NSF) and the National
Aeronautics and Space Administration (NASA) have jointly
achieved a new milestone in the almost 20-year history
of scientific ballooning in Antarctica, by launching and
operating three long-duration sub-orbital flights within
a single Southern-Hemisphere summer.
Scientists from the United States, Japan, South Korea,
France and other international collaborators concurrently
are using high balloons to investigate the nature of ultra-high-energy
cosmic rays and searching for anti-matter, as air currents
that circle Antarctica carry the balloons and their instruments
at the edge of space.
The University of Maryland's Cosmic Ray Energetics And
Mass (CREAM) payload was launched on Dec. 19; the Balloon-borne
Experiment with a Superconducting Spectrometer (BESS-Polar
) payload from NASA's Goddard Space Flight Center and
Japan's High Energy Accelerator Research Organization
(KEK) was launched on Dec. 22; and Louisiana State University's
Advanced Thin Ionization Calorimeter (ATIC) payload was
launched on Dec. 26.
The ability to launch and operate three balloon payloads
over Antarctica is the result of a partnership between
NASA and NSF, which provides logistic support for all
U.S. scientific operations in Antarctica. NSF facilitated
the launches near McMurdo Station, its Antarctic logistics
hub, and will recover the payloads after the flights.
Karl A. Erb, who heads NSF's Office of Polar Programs,
noted that the flight record, while significant itself,
is one aspect of wider cooperation in the polar regions
between NSF, which manages the U.S. Antarctic Program,
and the space agency. "This annual scientific balloon
expedition demonstrates the deep commitment and very fruitful
collaboration between NASA and the NSF that enables a
wide variety of forefront scientific research in Antarctica,"
he said. "Just as NSF provided the infrastructure
and logistics support that made this hat trick possible,
NASA provides the satellite communications link that is
the lifeblood of astrophysics research at our new research
station at the South Pole. Our partnership benefits both
agencies and more importantly, the U.S. Science community.
"This collaboration began in 1989, initially with
one balloon launch every other year, turning very soon
to every year, then increasing to two launches per Antarctic
summer at the end of 1990s and beginning of this decade.
Demanding science and excellent atmospheric conditions
over the Antarctica in the austral summer led our two
agencies to sign an agreement in 2003 aimed at increasing
the launch tempo to three balloons per season. With modest
investments but considerable effort by both agencies,
this goal is now achieved," Erb added.
Erb also noted that the milestone is particularly significant,
as it occurs during the height of the International Polar
Year (IPY), a coordinated scientific campaign that is
engaging scientists from more than 60 nations. NSF is
the lead federal agency for IPY, which began in March
2007 and will continue until 2009 to allow for two full
years of observations and field work in parts of the world
that are generally uninhabitable for as long as six months
each year.
W. Vernon Jones, senior scientist for suborbital research
at NASA headquarters, added, "We are extremely proud
of our crew in Antarctica, and the partnership with NSF
that provides for the increased capability to support
three payloads from McMurdo. This is indeed a crowning
event in the exceedingly successful NSF-NASA cooperation
in Antarctic long balloon flights."
Unique atmospheric circulation over Antarctica during
the austral summer allows scientists to launch balloons
from a site near McMurdo Station and recover them from
very nearly the same spot weeks later, after the balloons
have circled the continent one to three. Antarctic flights
are of a long duration because of the polar vortex, a
persistent, large, low-pressure system, and because there
is very little atmospheric or temperature change. Constant
daylight in Antarctica means no day-to-night temperature
fluctuations on the balloon, which helps the balloon stay
at a nearly constant altitude for a longer time. These
three payloads will ride the stratospheric winds in the
polar vortex above the Antarctic continent for up to six
weeks.
This orbital pattern allows for very long and continuous
observations of a variety of phenomena from a single instrument
at a fraction of the cost of launching an orbital platform
into space. Once the balloon flights are completed, the
payloads will be retrieved, brought back to McMurdo, and
then shipped back to the United States, where they are
refurbished and then launched again.
"With the launch of the CREAM, BESS, and ATIC missions,
NASA and NSF have realized a goal we have worked toward
for several years in order to accomplish more science"
said David Gregory, assistant chief of NASA's Balloon
Program at the NASA Wallops Flight Facility in Virginia.
"Having three long-duration balloon science missions
flying simultaneously is a record-setting event that we
in the Balloon Program and the Office of Polar Programs
are very excited about. But of greater significance is
that more science can be accomplished with a modest increase
in cost to the program."
Each of these large-aperture instruments is similar in
size to an observatory class satellite.
"The operations support for three balloons in the
air at one time, and using the finest balloon vehicle
made for this kind of cutting-edge scientific research
is a major achievement," said Jones. "If all
three of these missions achieve their flight goals, this
Antarctic campaign will result in more than 90 days of
near-space flight at an average altitude above about 37
kilometers [23.9 miles] with experiments averaging more
than 2000 kilograms [4400 pounds]. This exposure would
be equivalent to an Explorer class MIDEX mission in orbit
for almost three years."
Supporting the three science teams, the staff from NASA's
Columbia Scientific Balloon Facility, Palestine, Texas,
launched the giant helium balloons.
"With the launch of the ATIC instrument, our third
during this campaign, we have put 32,000 pounds of hardware,
including 13,000 lbs of science instruments, into near
space in a span of just over a week. It's a magnificent
accomplishment," said Danny Ball, site manager for
New Mexico State University the operator of the CSBF for
NASA. "We're extremely proud of our personnel who
worked through Thanksgiving, Christmas, and New Years
in harsh conditions in Antarctica to make this possible."
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NSF
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