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While large compared to a human, BARREL balloons are actually much smaller than typical science balloons, which can be as large as a football field. Credit: NASA/Goddard/BARREL/Brett Anderson Read more: <a href="http://www.nasa.gov/content/goddard/nasas-barrel-returns-successful-from-antarctica" rel="nofollow">www.nasa.gov/content/goddard/nasas-barrel-returns-success...</a> -- Three months, 20 balloons, and one very successful campaign. The team for NASA's BARREL – short for Balloon Array for Radiation belt Relativistic Electron Losses -- mission returned from Antarctica in March 2014. …
