Discovered : by Sir William Ramsay in London, and independently by P.T. Cleve and N.A. Langer in Uppsala, Sweden in 1895 Origin : The name is derived from the Greek ‘helios’, sun Description : A colourless, odourless gas that is totally unreactive. It is extracted from natural gas wells, some of which contain gas that is 7% helium. It is used in deep sea diving for balloons and, as liquid helium , for low temperature research. The Earth’s atmosphere contains 5 parts per million by volume, totalling 400 million tonnes, but it is not worth extracting it from this source at present. Image : Solar flares. Helium animation - click the icon above to launch. (Quicktime required) For more 109 Project animations click here.