Complex computer programs have been written to reconstruct the observed arrangement of magnetic fields emanating from the Sun. By following the evolution of the field as it is carried around and twisted up by the Sun's rotation, and by modelling how different parts of the field can merge or disappear, it is even possible to produce solar "weather forecasts" a few days into the future.

	The computer reconstruction of the solar corona on 21 October 2000 from which the Sun sculpture was produced. The lines show the structure of the coronal magnetic field, and the orange globe beneath shows the field strength at the Sun's surface.

The above model, used to produce the Sun sculpture, was generated using one of the most advanced computer models of the solar corona in the World. It was produced at the Lockheed Martin Solar and Astrophysics Laboratory by solar astronomers Drs Markus Aschwanden, Marc DeRosa and Carolus Schrijver. This model reproduces the structure of the solar coronal magnetic field as it appeared on 21 October 2000. As the image shows, the Sun was in a fairly active state that day, with a number of complexes of magnetic loops, and two large "coronal holes" in which open field lines leave the Sun and offer a route for charged particles to escape.