Although shields and sophisticated maneuvers could help protect space structures, scientists have to prepare for the possibility that debris could pierce a vessel. NASA and a team from the University of Michigan developed a new material that heals itself within seconds and could prevent structural penetration from being catastrophic.

The self-healing material sandwiches a reactive liquid in between two layers of a solid polymer. When the researchers shot a bullet through the material, the liquid quickly reacted with oxygen from the air to form a solid plug in under a second.

The technology could also apply to other more earthly structures, including automobiles.

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