Scientific balloons achieve flight record in Antarctica

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.

Potent partnership
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 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,"

The milestone is particularly significant, as it occurs during the height of the International Polar Year (IPY), Erb added. 

Foto: The National Science Foundation


Long observation
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.

Each of these large-aperture instruments is similar in size to an observatory class satellite. 

90 days near-space flight
"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] W. Vernon Jones, senior scientist for suborbital research at NASA headquarters explained.

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.

Source: The National Science Foundation