  A loosely bound hadronic molecule produced by a relativistic heavy-ion
collision has been described as a "snowball in hell" since it emerges from a
hadron gas whose temperature is orders of magnitude larger than the binding
energy of the molecule. This remarkable phenomenon can be explained in terms of
a novel thermodynamic variable called the "contact" that is conjugate to the
binding momentum of the molecule. The production rate of the molecule can be
expressed in terms of the contact density at the kinetic freezeout of the
hadron gas. It approaches a nonzero limit as the binding energy goes to 0.
