Space- a definition    Space; is a term which has many meanings. The meaning that is being referred to in this web-site is ‘the region beyond Earth’s atmosphere'.  Space is a vacuum, meaning that it has no pressure, but bodies such as stars, planets, asteroids and comets are scattered throughout. We humans live on a planet called the Earth which exists in what we call the solar system; consisting of many planets revolving around a single sun. The Solar System is located in one of the spiral arms of our galaxy; the Milky Way Galaxy which is made up of between 100 and 200 billion stars. Our Galaxy is surrounded by many other galaxies making up a galaxy cluster (called by scientists the ‘local group' which is again encircled by more clusters forming super clusters; one of which, called the ‘Great Wall' stretches across more than half a billion light years of space. Scientists believe that the bizarre structures of these galaxies are shaped by dark matter which exists in sufficient quantities to produce the gravitational field responsible for these formations. All of this is what constitutes of our universe (between 12 and 20 billions years old; created by the big bang) which, again as scientists believe, is not alone but is surrounded by even more universes, creating a multi-verse. In fact, there are more stars in our universe than grains of sand on Earth; so the sheer magnitude of the universe, or multi-verse  is  unimaginably colossal.