Acoustic Metamaterials: Shaping the Future of Sound and SilenceFrom stealth submarines to silent cities, acoustic metamaterials are transforming how we hear—and don’t hear—the world around us. Introduction Acoustic metamaterials have emerged as a groundbreaking technology capable of manipulating sound waves in ways that traditional materials cannot. Initially developed for military …

Introduction NASA’s Space Technology Mission Directorate (STMD) marked a pivotal milestone in July 2024 by publishing the results of its first-ever integrated civil space shortfall ranking. This initiative identifies and prioritizes critical technology shortfalls—areas where current capabilities fall short of future mission requirements. The report consolidates feedback from across NASA, …