IONIZATION SPECTROMETER

The instrument consisted of three major components a charge measuring module, a spark chamber for determining particle trajectories, and a ionization spectrometer for measuring total energy.

Balloon launched on: 11/11/1970
Launch site: Holloman Air Force Base, Alamogordo, New Mexico, US  
Balloon launched by: Air Force Cambridge Research Laboratories (AFCRL)
Balloon manufacturer/size/composition: Zero Pressure Balloon Mylar Scrim 26.000.000 cuft
End of flight (L for landing time, W for last contact, otherwise termination time): 11/12/1970
Balloon flight duration (F: time at float only, otherwise total flight time in d:days / h:hours or m:minutes - ): 14 h 25 m
Landing site: Payload landed near Orangeburg, South Carolina, US. The balloon continued flight and was last seen 500 miles E of Bermuda
Payload weight: 6000 pounds

The balloon was launched from Holloman Air Force Base, New Mexico on November 11, 1970. After a nominal ascent phase, the 27-million-cubic-foot balloon reach the planned float altitude of 110.000 feet. Data from the experiment was transmitted to ground stations at Holloman AFB, Fort Walters, Texas; The Marshall Space Flight Center in Alabama and the NCAR facility at Palestine, Texas.

Trouble started when the Air Force control package failed to respond to command from the ground causing the balloon to drift past the Texarkana site where the experimenters had planned to release the payload. The balloon continued in an easterly direction, moving quickly with the 50 knot winds that were blowing above 100,000 feet. During the following night it cooled, lost altitude and finally touched ground to drag and dump its payload in the woods near Orangeburg, South Carolina.

At this time it was not definitely known that the package had been left behind. The Goddard tracking network alerted radar facilities at Wallops Island and later at Bermuda to watch for the balloon. Meanwhile, an extensive land search located the package, which was later returned to Goddard. When last sighted, the balloon was 500 miles east of Bermuda and headed for Morocco.

During the flight, measurements of the differential energy spectra of the heavy nuclei of the galactic cosmic radiation was acomplished. Data obtained includes 20 hours at 12K bits rate on approximately half a million events.

• Cosmic-Ray Proton and Helium Spectra above 50 GeV Phys. Rev. Lett. 28, 985 (1972)
• Measurement of the Primary Cosmic electron Spectrum from 10-GeV to About 250-GeV NASA Goddard Space Flight Center; Greenbelt, MD, United States (1975)
• Results on the energy dependence of cosmic-ray charge composition Astrophysical Journal, Vol. 186, pp. 109
• The eventful flight of a Goddard balloon Goddard News Vol. 18 Nº 9, December 14, 1970, pag. 9
• The Shape of the Primary Cosmic Ray Electron Spectrum Above 10 GeV 13th International Conference on Cosmic Rays, Denver, Colorado, Volume 1., p.347
• Variations of the Carbon+Oxygen to Iron and the Primary to Secondary Ratios with Energy from 2 to 50 GeV/Nucleon 13th International Conference on Cosmic Rays, Volume 1, p.157