2017-11-17 - Martinez, CA - Formation

Eight white spheres observed against clear blue sunny skies & vanished before the observer could take a photo.

Friday, 11-17-2017 at 13:17, I heard a loud, low flying helicopter, which prompted me to go outdoors & observe. The day is sunny, clear blue skies, wind NE prox. 8mph. The ‘chopper’ is flying north bound, about 45 degrees above the horizon, & is white with some black markings. High above the chopper, about 15k-20k feet, is a tight group of 8 white spherical objects, some dark underneath, about 1/8inch diameter as viewed from ground. The formation is not moving except for 3 which are moving in various directions, then the entire group proceeds to move slowly SW.

I ran to get my camera, which took under 5-seconds, I fired up the camera & the objects disappeared. Gone, before my eyes, & unable to snap a picture. The chopper had passed, still heard distantly, however, I could not see the objects anywhere in the clear blue skies.
They were not birds nor balloons.

Sighting lasted about 1-2 mins.

My background: 66yrs., careers in medicine, & construction/engineering.