  In the last decade, there has been great progress in predicting and
synthesizing polyhydrides that exhibit superconductivity when squeezed. Dopants
allow these compounds to become metals at pressures lower than those required
to metallize elemental hydrogen. Here, we show that by combining the
fundamental planetary building blocks of molecular hydrogen and ammonia,
conventional superconducting compounds can be formed at high pressure. Through
extensive theoretical calculations we predict metallic metastable structures
with NH$_n$ ($n=10,11,24$) stoichiometries that are based on NH$_4^+$
superalkali cations and complex hydrogenic lattices. The hydrogen atoms in the
molecular cation contribute to the superconducting mechanism, and the estimated
superconducting critical temperatures, $T_\text{c}$s, are comparable to the
highest values computed for the alkali metal polyhydrides. The largest
calculated (isotropic Eliashberg) $T_\text{c}$ is 179~K for $Pnma$-NH$_{10}$ at
300~GPa. Our results suggest that other molecular cations can be mixed with
hydrogen under pressure yielding superconducting compounds.
