Helium is lighter than air which is why balloons float and rise. The higher a balloon rises into the atmosphere, the more the air pressure around the balloon will decrease causing the balloon to expand. If a balloon is overfilled, it will most likely burst or shatter. If a balloon doesn’t burst, then eventually some of the gas inside the balloon will diffuse out until eventually, causing the balloon to descend.

 

Interesting Balloon Facts

  • Experts say a standard balloon can float as high as 10 km above sea level depending on the quality of the balloon, compared to professional quality meteorological balloons that can reach heights of 30 km.
  • Regular balloons do not reach outer space because they freeze and pop when they rise very high too quickly, causing the balloon to become brittle and shatter.
  • There have been cases of balloons rising as high as an airplane in flight. In even rarer instances, balloons were sucked into the engine of a plane causing malfunctions and accidents. 
  • Anytime meteorological balloons are launched, the Federal Aviation Administration (FAA) or other governing agencies for aviation safety and warnings are notified. 
  • A case study from 1992 says foil balloons only rise 3,280 feet before bursting or losing its ability to float. 


Concerns

  • Balloons should never be intentionally released into the atmosphere as they are an environmental hazard and harms wildlife.