Going Higher and Longer

NSF, NASA test new balloon for next generation of high-altitude

Jan 9th 2011, 08:11

From the National Science Foundation
Posted January 9, 2009

The National Science Foundation (NSF)  and the National Aeronautics and Space Administration (NASA)  have successfully launched and demonstrated a newly designed super-pressure balloon prototype that will one day enable a new era of high-altitude scientific research. The super-pressure balloon is expected to ultimately carry large scientific experiments to the brink of space for 100 days or more.

“This flight test of NASA’s 7-million-cubic-foot super-pressure balloon is a very important step forward in building a new capability for scientific ballooning based on sound engineering and operational development,” said W. Vernon Jones, NASA’s senior scientist for suborbital research at NASA Headquarters in Washington. “While the team has a ways to go in scaling up the pumpkin balloon to be able to lift a one-ton instrument to a float altitude of 110,000 feet, the team has demonstrated they are on the right path.”

The test flight launched Dec. 28, 2008, from McMurdo Station , NSF’s logistics hub in Antarctica. NASA and NSF conduct an annual scientific balloon campaign  during the Antarctic summer. NSF manages the U.S. Antarctic Program  and provides logistic support for all U.S. scientific operations in Antarctica.

The balloon reached a float altitude of more than 111,000 feet. It continued to maintain a nearly constant altitude as of the 11th day of flight. The purpose of this flight is to test the durability and functionality of the scientific balloon’s unique pumpkin-shaped design and its novel material, a lightweight polyethylene film. The new material is a special co-extruded polyethylene film, about the thickness of ordinary plastic food wrap.

“Our super-pressure balloon development team is very proud of the tremendous success of the test flight and is focused on continued development of this new capability to fly balloons for months at a time in support of scientific investigations,” said David Pierce, chief of the balloon program office at NASA Goddard Space Flight Center’s Wallops Flight Facility , Wallops Island, Va. “The test flight has demonstrated that 100 day flights of large, heavy payloads is a realistic goal.”

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 times.

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.

The advantage of such balloon-borne experiments is that they cost considerably less than a satellite and the scientific instruments flown can be retrieved and launched again.

This 7-million-cubic-foot balloon is the largest single-cell, super-pressure (fully-sealed) balloon ever flown. When development ends, NASA will have a 22-million-cubic-foot balloon that can carry a one-ton instrument to an altitude of more than 110,000 feet — three to four times higher than passenger planes fly.

In addition to the super-pressure test flight, two additional long-duration balloons were launched from McMurdo during this year’s campaign. The University of Hawaii Manoa’s Antarctic Impulsive Transient Antenna (ANITA)  launched Dec. 21 and was still aloft as of Jan. 8. Its radio telescope is searching for indirect evidence of extremely high-energy neutrino particles, possibly coming from outside the Milky Way galaxy.

The University of Maryland’s Cosmic Ray Energetics and Mass (CREAM IV)  experiment launched Dec. 19 and landed Jan. 6. CREAM directly measures high-energy cosmic-ray particles arriving at Earth after originating from distant supernova explosions elsewhere in the Milky Way galaxy