Zig Zagging Egg in daytime

It was early Fall 1965, late afternoon and we had just had some rain.  The rain had stopped and dark gray clouds were skudding overhead.  
My parents went outside with my sister and for some reason I was still in the house.  
As I was going through the dining room area to get to the back door I passed a window looking toward the East.  Something caught my eye in the sky over some trees.  It appeared to be a egg shaped object that was emitting its own brilliant light source.  Not silver but like an egg shaped light bulb in the sky.  It really stood out against those gray clouds.  It was coming toward where I was watching it out the window and it was really moving.  
At first the movement of it really puzzled me because it was going back and forth advancing toward me until I realized that it was in a zig zag motion horizonally while flying.  Then the object streaked out of the window space while making a sharp turn toward the west where I lost sight of it.  
I burst out the back door and caught a very quick look at it as it went through the sky at an incredible speed through a break in the trees.
This object crossed a large part of the sky in just a blink of an eye and made absolutely no sound.  No plane or jet could do that back then or now and be lit up like this thing was.  
Of course I just happened to be passing the window when I saw it but since it made NO sound my family, who were outside at the time, missed it completely because there was no reason to look up.
Witness indicates that the date of the incident is approximate.  PD