New Study Reveals Complexity of Cosmic Ice Compared to Earth Ice

In a groundbreaking study, scientists from University College London (UCL) and the University of Cambridge have unveiled significant differences between cosmic ice and the ice found on Earth, shedding new light on the nature of low-density amorphous ice prevalent in space. The research, published in the *Physical Review B* on July 9, 2025, challenges long-held assumptions about the structural properties of ice formed under the extreme conditions of outer space.

Traditionally, researchers believed that ice in space, due to its formation in the near-vacuum conditions of the cosmos, lacked the energy necessary to form ordered structures, resulting in a completely random arrangement of molecules. However, the new findings indicate that this assumption may be overly simplistic. Lead author Michael B. Davies, a professor at UCL, explains, "We now have a good idea of what the most common form of ice in the Universe looks like at an atomic level. This is important as ice is involved in many cosmological processes, such as planet formation and galaxy evolution."

The study utilized advanced molecular dynamics simulations to model how water vapor condenses at temperatures around -120 °C (-184 °F), representative of environments conducive to the formation of amorphous ice. These simulations were then validated against archival X-ray diffraction data from laboratory-synthesized samples. The results revealed that approximately 20 percent of the simulated ice structure consisted of orderly nanocrystals embedded within a disordered matrix, akin to structures found in DNA.

The implications of this discovery extend beyond astrophysics. For instance, Christoph Salzmann, a co-author and researcher at UCL, emphasized the relevance of these findings to materials science: "Everyday technologies—from fiber-optic cables to pharmaceutical tablets—depend on truly amorphous solids. Our results raise questions about amorphous materials in general, which have important applications in advanced technology."

Additionally, this research may influence theories related to the origins of life on Earth. Astrobiologists have long posited that comets could have delivered the building blocks of life, such as amino acids, to our planet. However, the presence of crystalline structures within space ice may limit the capacity of such ice to store organic molecules, as Davies notes, "A partly crystalline structure has less space in which these ingredients could become embedded."

The research team conducted experiments to fabricate various forms of amorphous ice in cryogenic chambers, simulating conditions found in space. They discovered that the manner in which the ice was formed influenced the final arrangement of crystalline structures, suggesting that these samples retain a “memory” of their formation processes. This finding raises further questions about the potential for different types of amorphous ice to exist in the universe, including the possibility of a completely structureless variant.

Looking forward, the team plans to investigate the factors influencing the size and fraction of nanocrystals within amorphous ice. Understanding these properties could refine climate models for icy celestial bodies and enhance planning for future space missions aimed at utilizing extraterrestrial ice for fuel. Professor Angelos Michaelides, another co-author, remarked, "Water is the foundation of life, but we still do not fully understand it. Amorphous ices may hold the key to explaining some of water’s many anomalies."

As researchers continue to unravel the complexities of cosmic ice, the study underscores the importance of understanding ice's various forms and properties, not only for astrophysical applications but also for advancing technology on Earth. The universe's most common ice is now viewed as a more sophisticated material than previously recognized, with implications that could redefine both scientific and technological landscapes.