Ballooning on the Ice

The Long Duration Balloon Project

Williams Field, Antarctica

by Jeffrey K. Peterzen

Photos by Cindy L. Fraze

With a float altitude of 120,000 to 130,000 feet the polyethylene balloon launched from Williams Field, Antarctica is nearly in outer space. One would expect most craft operation at this altitude to be rocket-powered. Not so with this oneit's helium powered. Fifty-two point six million cubic feet of helium to be exact. Fully inflated the balloon, made of sixteen acres of material and requiring twenty six miles of seams, has a diameter of five hundred and eighteen feet. In ascent mode, from payload to the tip. the entire balloon (including the umbilical, parachute and payload), measures more than 900 feet. By contrast, the Washington Monument is some 350 feet shorter! This long duration balloon, or LDB, is capable of carrying more than 5,000 pounds of payload. That's impressive when compared to the 407-pound capacity the balloons carried in 1964.

Created by the National Scientific Balloon Facility of Palestine, Texas, the balloons are used to collect data in the oxygen-depleted upper atmosphere several miles above the earth. The types of research for which the balloons are used are: Cosmic Ray studies, Gamma Ray and x-ray Astronomy, Optical and Ultra-Violet Astronomy, Infrared Astronomy, Atmospheric Sciences, Magnetospherics and Micrometerorite Particles study.

The NSBF was established in Boulder, Colorado in 1961 under the auspices of the National Science Foundation. The facility was moved to Palestine, Texas in 1963 and designated as the National Scientific Balloon Facility in January 1973.

In 1982, sponsorship of the NSBF was transferred from the National Science Foundation to the National Aeronautics and Space Administration and the NSBF became a separate entity under the University Corporation for Atmospheric Research.

In October 1987, the NASA contract to operate the NSBF was awarded to the Physical Science Laboratory under the auspices of New Mexico State University located in Las Cruces, New Mexico. The contract is administered by Goddard Space Flight Center's Wallops Flight Facility.

The upper atmosphere above Antarctica provides an ideal environment for these balloons to operate. With 24 hours of sunlight to power the payload's solar panels, the balloon is able to maintain a constant temperature. This lake of diurnal (day to night) fluctuation allows the balloon to maintain a constant altitude.

As an employee of Antarctic Support Associates I was fortunate enough to be present for, and film, the 1997-1998 season launch of the LDB. The launch site on the Ross Ice Shelf is just six miles from McMurdo Station, one of three stations held by the United States Antarctic Program. I am also fortunate to be a good friend (and the brother) of Project Coordinator Steven Peterzen.

In preparation for the launch of the main balloon, project coordinator Peterzen first launches a much smaller "Pathfinder" balloon. this is done in an effort to chart the anticyclone winds above Antarctica that the main balloon will ride on so that Peterzen may better be able to forecast the trajectory of the LDB's launch and inevitable landing.

Peterzen also points out that these balloons are much more cost effective than a rocket launch. "We launch, monitor and retrieve these balloons with an eight-person staff. A rocket launch requires hundreds of people." In addition, at $100,000 each the balloons are hundreds of thousands of dollars cheaper than a rocket.

Cost is not the only attraction that balloons offer over their rocket powered rivals. Provided that all goes well with the anticyclone winds, Peterzen can expect between 15 and 20 days of constant data collection. By contrast, a rocket or shuttle might provide only a few hours of observation.

One caveat does exist, however. The LDB operates in the stratosphere which is shy of true space. this area of the atmosphere offers up some interference which is not present in true space.

During the LDB flight of 1997-1998 one of the experiments aboard was the High Resolution Gamma Ray Spectrometer. Weighing in at some 4,000 pounds, the HIREGS looks for all the worlds like a lunar module or communication satellite. Drawing power from its solar panels the entire machine draws only 350 watts of electricity.

The goal of the HIREGS is to view and record the Gamma Ray and x-ray portions of the electromagnetic spectrum in the galaxy. Dr. Peter Von Ballmoos and Dr. Mike Pelling are researchers that worked on the HIREGS project. The Gamma Ray and x-ray portion of the electromagnetic spectrum is "violent and unpredictable," said Van Ballmoos. "Gamma Ray bursts are so powerful they release the same energy emitted by 100 billion stars in one year, in just one burst. These bursts have never been recorded by such a precise instrument."

According to Von Ballmoos the language of the stars is in the colors. Eight thousand color pixels to be exact. Gathering this spectral information in the form of colors, researchers are able to make an analogy between the energy of individual photons they view and the colors they represent in our visible spectrum.

This, along with other data collected, will be transmitted, during flight, to an LC-130 aircraft flying below the balloon. This extra measure is taken to ensure that at least the data collected during the flight of the LC-130 will not be lost should there be a problem bringing the balloon back to terra firma, Peterzen says. "It's really tricky bringing these balloons back to earth," said Peterzen. "[The balloon] is flying at 125,000 feet for 20 days over mountains and open waterthat's a tough spot."

When Peterzen decides it's time to bring his balloon back home, he'll gather weather information and wind speed/direction in an effort to bring the balloon down in an area that is easily accessible for him and his crew to recover its precious payload.

Once he's ready to initiate the decent of the balloon, Peterzen will send a radio signal to the balloon, opening valves that release helium. Then, at a predetermined altitude Peterzen will send another signal to the "terminate" fitting on the balloons umbilical. This signal will "explode" the fittingfreeing the payload and attached parachute from the main balloon. Peterzen will perform this while observing the balloon from an LC-130 aircraft.

Hopefully Peterzen's balloon will hit close to its target landing area so that he and his small crew can find it and load it all aboard the ski-equipped aircraft for the trip back to Williams Field.

Not all goes well with every decent. In 1994 a mechanical failure sent a balloon and its payload down in Wohlschlag Bay off Cape Royds nearly 25 miles from McMurdo Station. Despite searching with SONAR, neither the balloon nor its payload was ever seen again.

I, for one, look forward to the 1998-1999 launch. Watching as a smile comes across Peterzen's face as his 900 foot baby climbs out of a site will always be one of the high points of my stay on the Ice each year.