View of the Planeterrella I. The vacuum chamber is made from Plexiglas. Its external diameter is 47 cm. The spheres (respectively 5 and 10 cm of diameter) are positioned on Plexiglas supports. The electric duct is positioned horizontally on the left of the picture on the bended Plexiglas arm. On the lower plate of the demonstration table, there is a power supply (white box on the left), a manometer monitor (black box in the middle) and a vacuum pump (orange, on the right).