Cosmic rays are produced by supernovae, the sun, and other explosions in the upper atmosphere. These cosmic rays are constantly impacting atomic nuclei which produces particles called pions. These pions decay very quickly into particles called muons. Muons have a mass that is 200 times that of an electron, which allows them to travel 99 percent the speed of light. Due to this, the muons can penetrate deep into Earth’s atmosphere and can sometimes even reach the surface. A device called a Geiger counter can be used to detect these muons as they enter the atmosphere. Using an altimeter to measure the altitude, the Geiger counter will measure the muon flux as it relates to altitude in the atmosphere. To measure the muon count as it correlates to altitude, the payload will be flown 30 km into the atmosphere via weather balloon.