Right now COVID-19 vaccines are traveling across the country and around the world – and air travel is a critical component of this supply chain. These vaccines were not only developed in record time (shout out to SCIENCE!) but some of them also have to be kept at record cold temperatures. To meet this challenge, distributors are relying on the cold chain – a supply line that keeps things cold (and sometimes super cold) from ‘source to sink’ (and hopefully soon, into your arm). On today’s episode we’re breaking down the history of the cold chain and how air safety plays a part (particularly with all that dry ice). And Emily has the best analogy of a lipid bilayer that you’ve ever heard.