These are all ways of measuring using things, physical objects in the world around us. But how do we measure how big a universe is? This is a video about the tools we use to answer that question.

The radar is a type of quantum sensor, an emerging technology that uses the quantum-mechanical properties of objects as measurement devices.

Mark R. Giovinazzi, Cullen H. Blake, Pedro H. Bernardinelli, Enhancing Ground-based Observations of Trans-Neptunian Objects Using a Single-epoch Parallax Measurement from L2, Publications of the ...