helium-filled balloon

NOAA balloon to measure ozone layer, South Pole station

Helium balloons – helium is lighter than air at ambient temperature, and that explains why helium balloons rise when they are let loose.

Helium-filled balloons are widely used

  • advertising – tethered helium balloons
  • meteorological studies – NASA’s Scientific Ballooning Program
  • atmospheric studies – NOAA ozone layer research

What do you think?

  • Have you had a balloon filled with helium? How is it different from a balloon filled with air that you blew up yourself?
  • Why are researchers using helium-filled balloons to lift instruments high above the earth?

Engineering ideas

  • ambient temperature, pressure, gases, density