Up, up and away
Giant balloons were in the news a lot this year, and NASA has some of the largest, which will launch early this month.
When most people think of NASA they think of astronauts and spacecraft, not balloons. But NASA has been using balloons for more than 30 years. Its Wallops Flight Facility in Virginia manages the agency’s scientific balloon flight program, with 10 to 15 flights each year from launch sites worldwide. This year’s most important flights begin early this month in the Antarctic.
“The annual Antarctic long-duration balloon campaign is the program’s flagship event for long-duration missions,” said Andrew Hamilton, acting chief of NASA’s Balloon Program Office. “The environment and stratospheric wind conditions provide a unique and valuable opportunity to fly missions in a near-space environment for days or weeks at a time.”
Why balloons
Balloon payloads are becoming more complex and more sophisticated, in many cases resembling spacecraft. However, balloon missions can be flown for a fraction of the cost of a satellite. Balloon science instruments range from telescopes that cover a wide range of the electromagnetic (light) spectrum to spectrometers that detect and quantify cosmic particles, as well as new and advanced subsystems for calibration, testing and validation purposes.
Highlighted mission
Headlining this year’s campaign is the Galactic/Extragalactic ULDB Spectroscopic Terahertz Observatory mission. The mission is led by principal investigator Christopher Walker from the University of Arizona with support from the Johns Hopkins University Applied Physics Laboratory. The goal is for 55-plus days in flight above the southernmost skies to map a large part of the Milky Way galaxy, including the galactic center and the nearby Large Magellanic Cloud.
They have a site for tracking the balloons here.
Sandwich bags
Both types of balloons are made of thin, polyethylene plastic film. The thickness is similar to that of plastic sandwich wrap. The most common size of NASA’s balloons is 40 million cubic feet. When the balloon is fully inflated, a high school football stadium could fit inside. Technicians inflate the balloons using helium.
Highest
The highest altitude achieved by a NASA balloon is about 160,000 feet. Most flights are 80,000 to 90,000 feet. The atmosphere at that height is incredibly cold. It’s near vacuum at balloon float altitudes.
Rising fast
The balloon typically rises at 1,000 feet per minute. It takes about two hours to reach a float altitude of 120,000 feet.
Sources: NASA, California Institute of Technology