  The interaction between two bright solitons in a dipolar Bose-Einstein
condensate (BEC) has been investigated aiming at finding the regimes when they
form a stable bound state, known as soliton molecule. To study soliton
interactions in BEC we employed a method similar to that used in experimental
investigation of the interaction between solitons in optical fibers. The idea
consists in creating two solitons at some spatial separation from each other at
initial time $t_0$, and then measuring the distance between them at a later
time $t_1 > t_0$. Depending on whether the distance between solitons has
increased, decreased or remained unchanged, compared to its initial value at
$t_0$, we conclude that soliton interaction was repulsive, attractive or
neutral, respectively. We propose an experimentally viable method for
estimating the binding energy of a soliton molecule, based on its dissociation
at critical soliton velocity. Our theoretical analysis is based on the
variational approach, which appears to be quite accurate in describing the
properties of soliton molecules in dipolar BEC, as reflected in good agreement
between the analytical and numerical results.
