  We report mass measurements of neutron-rich Ga isotopes $^{80-85}$Ga with
TRIUMF's Ion Trap for Atomic and Nuclear science (TITAN). The measurements
determine the masses of $^{80-83}$Ga in good agreement with previous
measurements. The masses of $^{84}$Ga and $^{85}$Ga were measured for the first
time. Uncertainties between $25-48$ keV were reached. The new mass values
reduce the nuclear uncertainties associated with the production of A $\approx$
84 isotopes by the \emph{r}-process for astrophysical conditions that might be
consistent with a binary neutron star (BNS) merger producing a blue kilonova.
Our nucleosynthesis simulations confirm that BNS merger may contribute to the
first abundance peak under moderate neutron-rich conditions with electron
fractions $Y_e=0.35-0.38$.
