An object viewed very close to me moveing slow. 250-300 ft. of altitude. I could hear popping and or snapping as streams of sparks or light of many colors dropped down. object black very rough 100 ft long 1/3 of length high. droping

I was working on my car, a sound like snapping and crackeling caused me to look and see a black object with a very rough surface moving slowly from south to north within 400-500 ft. from me. There were, as it looked sparks falling off the retreating end and falling straght down toward the ground. The lights were of many colors. There was a background reference of a tree line. I was able to estimate the size. This object was 100-150 ft. long and 1/3 that length high. This experience happed a long time ago but is peminently etched in my mind. I witnessed this and it has bothered me ever since. The object made no other sounds it was not anything of this planet unless the government has such technology for antigravity! I am relectant to report this but maybe it is helpful. I do not want to be called nuts! From time to time I have wanted to tell the authorities but you can understand the fears. This is my brothers computer and came across your website. I am 46 years of age now and I am convinced of other technology. Is it ours? Or from somewhere else. My brother, mother and father saw me very disturbed after the sighting. This object now as I have understood the stealth technology, was similar to how the surface on this object would reflect radar. But in the year 1970-'71?