Controlling chemical reactions near absolute zero

It is an understatement to say that chemical reactions take place everywhere, constantly. In both nature and the lab, chemistry is ubiquitous. But despite advances, it remains a fundamental challenge to gain a complete understanding and control over all aspects of a chemical reaction, such as temperature and the orientation of reacting molecules and atoms. This requires sophisticated experiments where all the variables that define how two reactants approach, and ultimately react with, each other can be freely chosen. By controlling things like the speed and the orientation of the reactants, chemists can study the finest details of a particular reaction mechanism.