Scientists have come up with nifty way to determine the temperature of super-tiny objects using Brownian motion.
Brownian motion is the random movement of tiny particles due to impacts with even smaller atoms or molecules. It was first noticed in 1827 by Botanist Robert Brown when pollen in very still water refused to stay still. Einstein in 1905 declared that the pollen was in fact moving due to the impacts with water molecules, essentially solidifying once and for all the fact that atoms and molecules really existed.
Fast forward to today…the temperature of microscopic and nanoscopic objects are notoriously difficult to determine. By suspending these objects in a special laser beam trap however, it is possible to infer its temperature by measuring the Brownian motion and the energies transferred between air molecules and nanoparticles.
This new technique may prove invaluable to many fields hoping to benefit from nanotechnology including electronics, biotech, and medicine. It may even help with efforts to bring macroscopic objects into a quantum superposition state. I like that last one, look it up.