Spotlight: Mylar Emergency Blanket for Camping & Survival

A thin membrane of aluminum. I learned that the engineers at the Marshall Space Flight Center designed this vacuum-metallized polyester in 1964 to shield satellites from the heat of the sun, but today the material populates the kits of mountain climbers and the pockets of travelers. The sheets measure fifty-two by eighty-two inches. The sheen catches the light of the moon. Physics dictates the warmth. Maybe I’m overthinking it, but the way the foil turns the wearer into a mirror for their own infrared radiation seems like a form of alchemy practiced in a laboratory. By reflecting ninety percent of the energy back toward the torso, the film prevents the loss of heat that would otherwise vanish into the black air of the troposphere. The material lacks any capacity for insulation against the soil. Sharp edges of the foil graze the skin when the wind catches the corners of the plastic. I meant to fold the material into its original pouch after a walk, but the air inside created a balloon that defied my fingers. A single snag on a branch or a jagged edge of ice will send a tear through the entire expanse of the two-ounce sheet. In the silence of the woods, the crinkling of the polyester mimics the sound of a storm.

Bonus Background

The Skylab mission in 1973 utilized these blankets as a desperate repair after a primary shield failed during the ascent into orbit. Workers at the factory deposit the aluminum onto the substrate through a vacuum-metallizing process. Each sheet costs two dollars and thirty-eight cents at the hardware store. The glare of the silver surface provides a signal for searchers in the clouds.

NASA Skylab Thermal Control History

Technical Analysis of Metallized Pellets and Films

The Alchemist's Foil Quiz

If you were to use this NASA film as a garment for a masquerade, what would the texture reveal about your secrets?

• A) The crinkling sound would announce your arrival before you entered the room.
• B) The reflection of the candles would hide your face in a bloom of white light.
• C) The sharpness of the edges would keep your dance partners at a distance.

Hypothetical Twist Answers:

1. If you chose A: You are a person who values the announcement of presence over the subtlety of movement. (Read: The Physics of Acoustic Propagation in Polymers)
2. If you chose B: You prefer to exist as a visual ghost, a trick of optics and light. (Read: Radiation Heat Transfer and Mirror Surfaces)
3. If you chose C: You use your environment as a defense against the intimacy of the crowd. (Read: Materials Science: The Tensile Strength of Mylar)