saw a blue sphere hover in front of me---just bigger than a basketball--no noise, heat, etc.--it took off and disappeared as soon as I

I was doing a paper route--delivering papers at 4am on Laukahi St., a hill up above where I lived (Honolulu)----had to be an adult route as the hill was so steep---
I would usually throw the paper to the porch of this particular home, but on this night (date is estimated but pretty close--year is for sure, as is time) the street light that illuminated the porch was not on, so I stopped my car, got out and walked to the porch of this home, perhaps 75 feet from the car--
I dropped the paper onto the porch, and as I was walking back towards my car ( which would have been north, away from the ocean, or mauka as we say in Hawaii), I noticed that the surrounding area had suddenly become illuminated in a bright blue light--
I turned around back towards the house---now facing south-- and observered an object that was coming over the roof of the house, maintaining a constant distance above the roof---I mean to say that it was as if it was staying a determinable distance above the house, like 2-3 feet, as if it was "measuring" or the like--my initial reaction, dumb as it was, was to think that it was one of those frisbees that you hold under a light and then throw, as it was "gliding" so uniformly over the roof--
micro-seconds later, I realized that this object was a sphere, and it "glided" down to about 5 feet above the walkway and then just hovered there, NO NOISE, NO SMELL, NO HEAT, NO NOTHING!!!  
I had turned to look at it, and stood there, perhaps 5-6 feet away from it as it just stayed 4-5 feet above the ground and did nothing---I was facing it---it was the size of a large basketball, or big watermelon-- and, as I recollect, as soon as my brain finally kicked into gear and I began to say to myself, "What the hell is that?", it took off, over the northward hill, so fast that all that I saw was a blue line in my vision, so fast that it was out of my sight in a second at most--again, NO NOISE!! 
I just finished my route, and at about 10am that same morning, as I sat at my desk, it hit me--What the hell was that??--It seemed that as soon as my mind started to ask "what is that?", that it was the catalyst for it to take off---no object could have been accelerated so quickly that we could manufacture--
no doubt in my mind that it was some kind of measuring probe, doing some kind of mapping---it hugged the roof of that house so precisely---like you were making a schematic, or 3-D map---I don't know---but it was there, 
I saw it, and I've shared this with, maybe, 5-6 people since 1979---what would be the point?? But I just saw your website on "Peter Jenning's" show, so I thought I'd let you know---it was not from this planet---guarantee you that---
aloha, ((name deleted)), Kaneohe, HI---808-((number deleted (HST!!) or e-mail to: ((name deleted))@hawaii.rr.com---keep up the good work!!! Aloha
Witness indicates that date of sighting is approximate.  PD