Imagine the Universe!

Tell Me About Flying Cosmic Ray Detectors On Balloons

Since cosmic rays do not penetrate very far into the earth's atmosphere, cosmic ray instruments have to get above most of the atmosphere. Satellites are excellent platforms for cosmic ray research, but a much less expensive method is to use high-altitude unmanned balloons. NASA has an active balloon program flying huge helium research balloons at altitudes of 40 km, above 99.5% of the atmosphere. The balloons fly for one or more days, after which the payloads return to the ground on a parachute. These payloads can weigh several tons, considerably larger than the typical satellite experiment, and have returned some of the most valuable results in cosmic ray research. They also serve as inexpensive test-beds for satellite missions of the future.

photo of IMAX launch

Examples of cosmic-ray balloon include IMAX ( (the Isotope Matter-Antimatter eXperiment pictured above) and ISOMAX ( (the ISOtope Magnet eXperiment).

Imagine the Universe is a service of the High Energy Astrophysics Science Archive Research Center (HEASARC), Dr. Alan Smale (Director), within the Astrophysics Science Division (ASD) at NASA's Goddard Space Flight Center.

The Imagine Team
Acting Project Leader: Dr. Barbara Mattson
All material on this site has been created and updated between 1997-2012.

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