I was in my outdoor hot-tub this evening, a dark, intermittently cloud-free night with good star viewing, noting occasional meteors, satellite passages, stars, constellations, etc. a very bright light (brighter than aircraft wingtip clearance lights) in constellation ursa major attracted my attention. noted dim starlike light (first one) moving generally northward from location of flash...Then it started a fairly-tight turn to starboard (ne->e->se-s), tighter than a commercial aircraft would have done at cruising altitude. i dried off, got out, took a seat in a lawn-chair for better, stabler viewing. time was approximately 10:40pm. within a few minutes, a second starlike object joined the first, they both flashed periodically, very bright, flashes lasting more than a second but probably not as long as two seconds. both objects maneuvered, in more-or-less circular path. high, thin clouds were making their way into the segment of sky where all this was going on, so my view became occasional fleeting glimpses of the objects on their 'dim' setting (comparable to a magnitude 2 or 3 star), but very clear sighting of the bright flashes (far brighter than any star, brighter than venus, mars, jupiter in most visible situations) through the thin cloud cover. about eight or ten minutes into this siting, a third starlike object, also flashing brightly at irregular times, approached from due-south, moving faster than a commercial jetliner, perhaps twice the apparent velocity. came right into the space the other two occupied, made a full circle maneuver (actually, about 450 degrees), then headed off eastward, flashing two more times that i saw. my impression was that these objects were at very high elevation, but i have little comparative evidence to substantiate this...Except that there was absolutely no sound, no visible structure to the objects, no perceptible dimension (note that i've characterized them as 'starlike'). if you asked for a guess as to elevation, i'd be forced to postulate perhaps 100,000 ft...Or higher...But it's just an impression. during the sighting, two conventional aircraft flew through the approximate same space of sky, flying due-south probably having departed out of pdx, probably at 10,000 or 12,000 feet but climbing to cruising altitude...This is the usual flight-path for commercial aircraft crossing over salem. these aircraft's navigation lights were clearly visible as separated, although their engine noise was not perceptible over ambient ground noise (traffic, neighbors, wind in trees, hot-tub pump, etc.) and no details of the fuselage, wings or empennage were distinguishable. point is, these aircraft (which did not interact with the sighted starlike objects at all, to my perception) appeared to be at far lower altitude than the starlike objects i've described. i am retired from a lifelong career in applied earth sciences, physical sciences, and education. i hold a b.Sci. with honors from uc berkeley, a m.Sci. in mechanical engineering from oregon state univ., and a second master's degree in education (specialties: physics, chemistry, advanced mathematics, computer science) from western oregon university. i offer all this high-powered academic boasting in the vein of establishing (a) something in the way of believable credentials, and (b) some form of affidavit of general sanity. i've never reported a ufo sighting in all my long years, but tonight's sighting was pretty unusual! it's unfortunate i was all alone, w/ no one around to back-up my sighting! i have to say, in all my 71 years, much of it spent in outdoor pursuits, i've never seen anything like this, and i cannot summon-up a plausible explanation dealing, for example, with high-altitude air force maneuvers, swamp-gas, reflections, re-entrant space debris, or delusional thinking on my part!