Gyroscopes the Size of Sand Will Track You Anywhere (Even Underground)S

The Israeli Department of Defense has cooked up the world's smallest gyroscope—powered by lasers and as small as a single grain of sand. The new gyros are sensitive enough to track your position and movements anywhere—no GPS required.

The underlying tech is the same that's found in aircraft and seafaring ships—minute physical changes are compared to each other, calculating a new position without the need for an external reference point. Essentially, the object (be it an aircraft carrier or something smaller) can detect itself moving. But for a gyro to be this tiny changes everything. Think of a smartphone that could pinpoint your movements in a cave—or, probably more realistically (and practically), a museum, or new apartment building. Sadly, we'll still need GPS a little bit, as the gyroscopes need to be told exactly where they are from above before their own internal detection can kick in. But this breakthrough will mean GPS access could someday be of minimal importance—which is great news (especially for any city dweller, who knows lining up a signal can be a pain at best). Just get one little satellite zap, and the micro-gyros will take it from there, anywhere in the world. [Pop Sci]