  The appearance of interstellar objects (ISOs) in the Solar System -- and
specifically the arrival of 1I/'Oumuamua -- points to a significant number
density of free-floating bodies in the solar neighborhood. We review the
details of 'Oumuamua's pre-encounter galactic orbit, which intersected the
Solar System at very nearly its maximum vertical and radial excursion relative
to the galactic plane. These kinematic features are strongly emblematic of
nearby young stellar associations. We obtain an a-priori order-of-magnitude age
estimate for 'Oumuamua by comparing its orbit to the orbits of 50,899 F-type
stars drawn from Gaia DR2; a diffusion model then suggests a $\sim$ 35 Myr
dynamical age. We compare 'Oumuamua's orbit with the trajectories of individual
nearby moving groups, confirming that its motion is fully consistent with
membership in the Carina (CAR) moving group with an age around 30 Myr.
  We conduct Monte Carlo simulations that trace the orbits of test particles
ejected from the stars in the Carina association. The simulations indicate that
in order to uniformly populate the $\sim10^6$ pc$^3$ volume occupied by CAR
members with the inferred number density, $n=0.2\,{\rm AU}^{-3}$, of ISOs
implied by Pan-STARRS' detection of 'Oumuamua, the required ejection mass is
$M\sim 500$ $M_{\rm Jup}$ per known star within the CAR association. This
suggests that the Pan-STARRS observation is in significant tension with
scenarios that posit 'Oumuamua's formation and ejection from a protostellar
disk.
