We use data from the Hipparcos catalog and the Barbier-Brossat & Figon cata
log of stellar radial velocities to test the hypothesis that the beta Pic p
lanetesimal disk was disrupted by a close stellar encounter. We trace the s
pace motions of 21,497 stars and discover 18 that have passed within 5 pc o
f beta Pic in the past 1 Myr. beta Pie's closest encounter is with the K2 U
T star HIP 27628 (similar to0.6 pc), but dynamically the most important enc
ounter is with the F7 V star HIP 23693 (similar to0.9 pc). We calculate the
velocity and eccentricity changes induced by the 18 perturbations and conc
lude that they are dynamically significant if planetesimals exist in a beta
Pic Oort cloud. We provide a first-order estimate for the evolutionary sta
te of a beta Pic Oort cloud and conclude that the primary role of these ste
llar perturbations would be to help build a comet cloud rather than destroy
a preexisting structure. The stellar sample is similar to 20% complete and
motivates future work to identify less common close interactions that woul
d significantly modify the observed circumstellar disk. For future radial v
elocity study, we identify six stars in the Hipparcos catalog that may have
approached beta Pic to within 0.1 pc and therefore remain as candidate dis
k perturbers.