CLOSE   APROACH   OBJECTS - CAO  
> 7,000 CAO,   > 7,000 Asteroids, & >100 Comets

Aten Asteroids Semi-Major Axis < 1 au,  # > 550
Apollo Asteroids Perihelion < 1 au,  # > 3,350
Amor Asteroids Perihelion 1 to 1.3 au,   # > 2,800

 POTENTIALLY  HAZARDOUS  OBJECTS - PHO 
Min.Earth Orbit Intersection < .05 au &  Diam. > 500'

> 1,200 PHA - Potentially Hazardous Asteroids
> 100 PHC - Potentially Hazardous Comets

Tom  Whitney    256-6234      E-Mail