There are three rings around the Unisphere. They show the orbits of Yuri Gagarin, John Glenn, and the Telstar satellite around the Earth. There were supposed to be more rings, but the designers could not do this. The rings are held up with aircraft cable. The Unisphere's continents and islands are made of many layers of metal sheets. The Unisphere has many latitude and longitude bars of different sizes. This makes the structure stable.