Lights 8-10 'v' shaped gliding across sky, no sound, gigantic, blacked out sky so no stars or planes could be seen.

Visiting my daughter in Tigard, Oregon to attend wedding and babysit while she went on honeymoon.  The evening of August 16, 1992 I went out on the patio to smoke a cigarette.  I was looking at the stars and watching planes fly overhead.  Then the sky suddenly became black--no stars, no planes.  Then the lights appeared--8 to 10 'v' shaped lights that appeared ahead of the blackness.  The lights and blackness slowly glided overhead in a westerly direction towards Portland, Oregon.  This thing was gigantic and I did not detect any sound as it passed overhead.  It was not moving fast like the airplanes I had seen just a few moments before, it was moving very slow.  I got up and started to walk across the backyard in the direction the lights were travelling, then the lights disappeared as if they had tilted upward, a few seconds later the stars and planes reappeared as if nothing had been there.  No light trails, nothing.  I was 51 at the time, not drinking, do not use drugs, not known to halucinate, divorced, owned my own business, two children at home.  I called my aunt who lives in the area the next day and told her what I had seen, also my granddaughter, and daughter's tenant.