Swap the big sphere for a loaded object.
The basic method is to use the INTERSECT OBJECT command which works by drawing an imaginary line between two points in 3d space and it tells you distance from start point to where it hits your object. I have therefore asked db to start from a point 1000 units above me and finish 1000 units below me and tell me how far it is from the point 1000 units above me to where it hits your object. Then just add 1000 to your current y position, take away the distance that intersect object gives you and then remember to add back how far above object surface you want your object (25 units in my example, which is radius of the little red ball)
The programmer formerly known as sonic