In the late 1930s, a team of physicists from the National Bureau of Standards (now
the National Institute of Standards and Technology) published eight papers on the
investigation of cosmic rays in the atmosphere. Payloads launched with weather balloons,
also known as radiosondes, were equipped with sensors to measure temperature, relative
humidity, pressure, and radiation dose. A battery-operated telemetry system was used to
continuously transmit at 60 MHz to a base station. They measured the radiation dose
profiles of cosmic radiation in the atmosphere up to 21 km. Calibration of the
Geiger-Müller counters with a standard radium source allowed them to calculate a
radiation dose rate at an altitude corresponding to 10 kPa that was 180 times the dose
rate near sea level in Washington, DC. Ascents in Washington, DC (latitude 39 degrees)
and Lima, Peru (near equator) allowed them to demonstrate the effects of Earth’s
magnetic field on incident galactic cosmic rays; the dose rate in Peru was only half
that in Washington, DC.
Radiation dose and its protection in the Moon from galactic cosmic rays and solar energetic particles: at the lunar surface and in a lava tube