The second of three speculative design concepts from VIS 161, spring 2022. The term "synthetic sensing" is mine. The ideas came first; the rationale followed, as it often does. The premise was straightforward enough to sketch in a few sentences, which is usually a sign that the idea is either very simple or very large. This one turned out to be the latter. Synthetic sensing, as I conceived it, is the use of AR and VR technology to extend human perception beyond its current ph