Europe remains highly dependent on non-European Space Situational Awareness data, limiting its ability to independently observe and understand the orbital environment. As human activity in Earth orbit accelerates, the population of active satellites and debris is growing rapidly, increasing safety and security challenges. Understanding what is in orbit, how objects behave, and what can be reliably observed and measured has become essential. This talk explores why existing Space Situational Awareness technologies encounter scaling challenges, and how new sensing and measurement approaches, grounded in physics, can expand what we are able to see and know. Closer collaboration between scientists, startups, established industry and defence actors is essential to build resilient European space capabilities.