Why are they called space blankets? They actually do have an interstellar connection.
NASA used the same shiny insulation material to protect many of its Earth-made crafts from the much harsher environment of space. It was first used as a parasol-type shield to keep Skylab from overheating after the spacecraft lost a heat shield during launch, according to NASA.
"Thermal blankets are to spacecraft as clothes are to people," Mike Weiss, the technical deputy program manager for the Hubble telescope, once said.
They have been used as emergency first aid: to warm marathon runners who experience a rapid cool-down after the finish line and shark attack victims who have lost a lot of blood. Mountaineers and campers use them frequently.
Hospitals use them to keep both medical staff and patients warm in the chilled environments of operating theaters. We lose body heat in different ways. By radiation, which is heat emanating from the surface of our skin and dissipating. We lose heat by convection, think of the wind blowing across your skin’s surface – nice on a humid day when we’re sitting in front of a fan, but bone chilling on a blustery winter day. And we lose heat by conduction, as when our pet lays on the couch, we then sit where they’ve been and can feel the 'warm spot' they left for us.
The blankets work to keep you warm by their very design. As an impermeable metalized plastic sheet, they trap up to 90% of the radiated body heat that would normally be dispersed into the environment. So they mainly keep us warm with the heat we’re already always generating and losing!
There have been so many space blankets that have washed ashore or been left behind near camps that several artists have made photographs, sculptures and even performance installations with the shiny stuff.
Space blankets are used to reduce heat loss from a person's body, but as they are constructed of PET film, they can be used for other applications for which this material is useful, such as insulating containers—e.g. for DIY solar projects—and other applications.
Artist Cristina Ghinassi's performance in Istanbul this year aimed "to explore the possible meanings of the protectiveness and the reflection given by the space blankets covering the bodies of migrants. Through the heat-reflective blankets, (the) artist uses her presence and body as a mirror to create a possible connection between her, the migrants and the audience."