Jeff Feddersen, author of EarthSpeaker, is an artist with a well rounded background, mainly specialised on the dynamics (nowadays pretty blended) between music and informatics. His favourite subjects of research are nature and the technologies developed around energetic sustainability. EarthSpeaker is a set of outdoor installations (sculptures) which interact with and within the environment by grabbing solar energy during daytime and releasing sound emissions from sunset on. Feddersen's project is at free103point9's Wave Farm in Acra (New York), and the first prototype of EarthSpeaker was built in 2006 at Eyebeam Center labs. Thanks to his 'nocturnal audio sculptures,' he seems to put up a sort of robotic representation of life-environment interaction and its seemingly simple cybernetic cycle. Just like the vegetal system, EarthSpeaker absorbs solar power thanks to the built-in solar panels and releases amplified VLF (very low frequency) sounds coming from outer space lightening and human generated waves (i.e.: geophones) by its own integrated speakers. A complete input/output cycle exploits the invisible and infinitesimal capabilities of our environment, redefining at the same time its semiotic borders through new representations of life.