* from a poem written by Percy Bysshe Shelley, ‘The Cloud’ (1820)
In 2014, on the occasion of the exhibition “The Anthropocene Monument”, initiated by Bruno Latour and Bronislaw Szerszynski at Abattoirs (the Museum of Modern and Contemporary Art, Toulouse), Tomás Saraceno presented an inflatable sculpture – a cloud made of plastic bags, titled Museo Aero Solar. Museo Aero Solar embodies a whole social movement and a collective, united under non-authorship and open source principles. By the side of this installation, the artist also displayed his first sketches and attempts at a bigger undertaking – the project of Aerocene. It was a different cloud, shaped as a sphere with silver reflections that expanded, and occupied almost all the exhibition space. The work became a central axis around which texts, research material and technical drawings, displayed together with the sculpture, were assembled, articulating the new way of aerosolar travelling.
Aerocene is based on a technology that was originally invented by the French National Space Agency (Centre national des études spatiales – CNES) thirty years ago. MIR – the acronym of an infrared balloon – was an ‘autonomous’ balloon for meteorological researches. It was flying around the globe at a height varying between 18km and 32km. It had been heated by the sun during the daytime, and maintained its altitudes at night because of infrared emissions from the Earth’s surface. This journey of MIR could have lasted for months, and this was precisely one of his flaws. Lacking sufficient trajectory control and being submitted to strict aviation laws, MIR balloons are now deflated and their silver shine is locked in storage boxes. Saraceno wishes to relaunch them, and see them circumnavigating the sky again. He even speculates at the possibility of travelling with one, and maybe even living in there, uplifted by the sun.
However, nobody is going to dwell there at the moment. The current shape of the global ecosystem makes Aerocene’s sculptures more similar to rescue boats than airy colonies of expansion. Diametrically opposite to Warhol’s silver clouds, presented in 1966, Saraceno’s work informs about the time of crisis and the deteriorating condition of the Earth. Visually resembling the droplets of mercury escaped from a thermometer, they call for the reparation of our common home Earth. Aerocene sculptures’ trajectory uses the numerous pathways and crossings of winds and jet streams. They do not care about (national) borders and call for a united global action. Consciously referring to the Anthropocene, Aerocene has its own ambiguities: its perspective can be seen as apocalyptic or dystopic, but it demonstrates the will to cope with deteriorating planetary shape with somehow joyous and merry means – collaboration and communitive actions. Aerocene as a multi-faceted project (assembling together different applications and modes of employment, solving technical obstacles that it passes with a soft, airy jump by its inventive spirit) could be seen as a geo-engineering undertaking. But in contrast to those technocratic projects that try to fill the atmosphere with micro-particles in order to reduce the global warming, Aerocene is a bold gesture of a sincere concern and social sensibility. Aerocene declares the stratosphere as a permanent autonomous zone (TAZ). Its artistic imagination draws on camping in the air and floating ‘tree’-cabins.
To situate the artistic project within its background – cloud- and skyscapes, a retrospective look can be taken. Art historian Hubert Damisch in his book A Theory of /Cloud/: Toward a History of Painting examines the celestial domes of Correggio, a Renaissance painter. Two cycles depicting breakings and collisions of an illusionary sea of clouds, created in Parma at the first quarter of the 16th century, were already speaking and showing the epistemological change that was still yet to come with the Copernican revolution. Furthermore, baroque and its shapes of clouds takes the society from the closed world to the infinite universe. During the first quarter of 21st century, Aerocene is a contemporary of the Anthropocene. It makes the limits of life on the planet tangible and comprehensive, on the contrary to the harsh-real utopian ideas of the techno-science. Floating in the levels of stratosphere, Tomás Saraceno’s sculptures draw the line of a certain demarcation. Similar to the yellow buoys in the water, separating safe waters from dangerous ones, Aerocene bears a paradoxical message: up from the sky it calls the necessity to be on the earth, well-grounded.
Within the celestial domes of Correggio and the ones of 17th century baroque, Hubert Damisch pays a special attention to the detail of “nuvola” (it. a cloud) that appears at the theatrical scenography from the Middle Ages. This essential element has made Christ, Virgin Mary and saints to fly, camouflaged by fake mechanical clouds in mystery plays of quattrocento. Mantegna and other painters used the “nuvola” in their sacred depiction. According to Vasari, we owe the clouds and their representations in art to Brunelleschi, one of the inventors and developers of the perspective in painting. “We notice how many painters have re-appropriated the different elements of theatre, depicted its scenography in the least problematic fashion” – notes Damisch. “Rocks that hide the dragon of Uccello [Saint George and the Dragon painting by Uccello] are made of carton, the clouds of Mantegna appear as wooden model covered by a painted canvas that was used to make scenography the most realistic. Mantegna does not seek to simulate or repeat the nature. The contrasting difference between atmospheric clouds and the mechanical-theatrical ones is a conscious gesture, referring not to the natural phenomena but to its cultural value.” The installations and actions of Tomás Saraceno are close to being a set of such a scenography. Illusions are visible, but the cultural or social values prevail over them. The art of Tomás Saraceno is not one of engineering, design or architecture. His genius lies in his capacity to construct technological objects that make the division between natural phenomena and a human individual disappear.
Jacques Roubaud in his short text Sky and earth and sky and earth, written 1987, speaks about the “permanent condition” of skies of John Constable. “The clouds [in his paintings] are paradoxical visualisations of perpetually changing traces of a fixed skyscape. These fixed representations bring some sort of permanence to us – the fixed moment of memory. The ever-changing sky has a permanence of that sort, since “cloud castles”, once destructed, are then again rebuilt, reassembled and reshaped by the wind. This type of transformation is much more sustainable than the one of earthly objects. Decomposition of vegetation, collapse of buildings and built structures, death of living beings – all designate the irretrievable past. On the contrary, constantly forming without ever attaining a fixed form, the vapor of the sky seems to be much more long-lasting.”  Saraceno’s project Aerocene aims to provoke, to bring to us similar feelings. Two centuries after the start of industrial revolution, the ever-changing but ever-lasting sky and the air has too become a subject of crumbling and decomposition. Aerocene thus is a signal at the border of the modern world, a world where humankind will consume the sky after it has already devoured the earth and the ocean.
— Olivier Michelon
 Silver Clouds is an installation, made by Andy Warhol and engineer Billy Klüver, exhibited in 1966 at the Leo Castelli Gallery.
 The concept of “permanent autonomous zones” is informed by the acclaimed text of critical cybernetic theory by Hakim Bey T.A.Z.: The Temporary Autonomous Zone (1991), and its later discussions as Permanent TAZs (by H. Bey 1994). PAZ defines more-or-less permanent counter-culture movements and communities, that share “the same ways of making” and same lifestyles, defined in opposition to cultural and political normativity.
 Damisch, H. (1972) Théorie du nuage. Pour une histoire de la peinture. Paris: Éditions du Seuil. 103.
 Roubaud, J. (1997) Ciel et terre et ciel et terre et ciel. Paris: Editions Argol. 81