First, it is dark, meaning that it is not in the form of stars and planets that we see. Observations show that there is far too little visible matter in the Universe to make up the 27% required by the observations. Second, it is not in the form of dark clouds of normal matter, matter made up of particles called baryons.
Livestock[edit] The raising of livestock, sheep (the traditional mainstay for generations of Icelandic farmers) and cattle (the latter grew rapidly in the 20th century), is the main occupation, but pigs and poultry are also reared; Iceland is self-sufficient in the production of meat, dairy products and eggs.
Tour One of Iceland's Incredible Geothermal Plants. The Svartsengi geothermal power plant produces 75 Mw of energy, provides thousands of homes with hot water, and created a hot lagoon that became a tourist attraction.