It is early morning on Brighton beach, and we are sitting on a slope of pebbles, looking out to sea. With us we have a laptop, several metres of cabling, and an antenna taller than a small child. In between waving off the attentions of men wielding metal detectors and some extremely large seagulls, we squint into the computer screen, looking for a specific peak on the radio spectrum. We are trying to see the invisible infrastructure that surrounds every part of our modern existence.

Our 21st Century lives depend on enormous logistics systems for nearly every part of our lives. Clothes, food, medicine, and phones all come into our lives through a tangled and complicated route of supply chains, container ships, planes, and trains. Around 85% of international freight is carried by sea, nearly 10 billion metric tonnes. Nearly every commercial plane carries some type of airfreight, mostly on the large ‘wide-body’ planes like Boeing 747s, with UK airports alone handling some 2.4 million tonnes in 2013. In the UK, trains carry around six and half billion metric tonnes of freight annually.

Yet despite their importance, infrastructures are designed to be invisible, operating smoothly and silently. We tend to only notice them when they malfunction or break – when a parcel goes missing, or when a train is delayed.