Ammonia (NH3) is a
compound with molecules each consisting of one
nitrogen and three hydrogen atoms.
It is a colorless gas, lighter than air and
is a weak base. It is a common component of
fertilizer.
Earth produces ammonia organically, and it is also found
in the solar system including on Pluto, the giant planets,
and some moons. It has also been detected in interstellar
space and in other galaxies. It can serve as the
material for both artificial and natural (astrophysical) masers.