For Fontana, drawing is the starting point and foundation of his artistic explorations. Each of his series begins on paper. He drew almost daily, pursuing and consolidating an idea over several sheets of paper. The drawing shows how the line moves from the surface into space. The term "Concetto Spaziale" (spatial concept) first appears in the works on paper made in Argentina in 1946.
The gouaches from 1950, mounted on canvas, show shapes, some in metallic colours, whose geometric shapes are accentuated by the refraction of light. They should be read as "volumes" that fully capture the three-dimensionality of space. They can be associated with mysterious geoids or celestial bodies in cosmic space, surrounded by an atmospheric, gaseous "aura" that resembles a cloud of stars.
Fontana was fascinated by the new technological inventions and advances of his time. Space travel in particular opened his eyes to the revolutionary changes that lay ahead. Art, too, would have to change if it was to keep pace with modernity.
In 1949, Fontana created "Ambiente spaziale a luce nera" (Spatial Environment with Black Light) at the Galleria del Naviglio in Milan. This was his first spatial installation. Fontana hung papier-mâché objects, reminiscent of his drawings, from the ceiling. These shapes were painted with neon colours and fluoresced in the space, which was lit only by black light.