Messages can be preserved in ice for millennia simply by altering the shape and positioning of the internal bubbles present.

Mengjie Song and his team at China’s Beijing University of Technology were exploring ice formation when they discovered that it influences the size and shape of bubbles encapsulated within. For instance, they found that freezing a layer of water between plastic sheets resulted in either oval or needle-shaped foam, depending on the freezing rate.

The researchers assigned specific bubble sizes, shapes, and positions to represent characters in Morse and binary code. By controlling the freezing rate of water, they created ice that conveyed messages through the embedded bubbles.

Transforming this ice image to grayscale revealed that white areas indicated the presence of bubbles, while black areas indicated the absence of them. This allowed computers to identify the size and location of bubbles for message decoding.

Currently, the amount of information that can be stored in conventional ice cubes is minimal with existing technology. However, Song suggests that by manipulating foam in materials like plastic, greater capacities could be achieved.

He mentions that beyond the novelty of reading messages embedded in ice cubes used in beverages, this research has diverse potential applications. “The strength of this study lies in its capability to sustain information over extended periods in frigid environments like the Arctic and Antarctic,” Song notes.

He envisions a future where bubbles could safely contain ozone for food preservation or act as carriers for slow-release medications. He is particularly intrigued by how bubbles can inhibit ice formation on airplane wings and how this knowledge could inform behavior in lunar environments.

However, Qiang Tang from the University of Sydney is more skeptical about the practical implications of this research, asserting that significant information can be long-term stored on hard drives and paper.

He comments, “This represents a novel method for conveying messages, but from a security and encryption standpoint, I see little value in it—unless, of course, a polar bear has something to communicate,” he adds.