The invention relates to a device for displaying a spherical object on a flat plane, characterized in that the device comprises a first disc with a projected image of the surface of a first hemisphere of the spherical object, and at least two second discs with a projected image of the surface of a second hemisphere of the spherical object. A preferred embodiment is a method for navigation, comprising the use of the device according to the invention, and a method for determining the time at any point in the world, comprising the use of the device according to the invention.

The invention relates to a device for displaying a spherical object on a flat plane, characterized in that the device comprises a first disc with a projected image of the surface of a first hemisphere of the spherical object, and at least two second discs with a projected image of the surface of a second hemisphere of the spherical object. A preferred embodiment is a method for navigation, comprising the use of the device according to the invention, and a method for determining the time at any point in the world, comprising the use of the device according to the invention.