Narrative:

While flying we encountered multiple unusual sightings at altitude. Around XA30Z at FL360; 20 mi north of tnp; I witnessed the first such event. I queried ATC about what I had seen; but was not too concerned at this point. It was unusual and unlike anything I had seen before; but lasted only around 10 seconds. I asked the first officer if he had seen what I saw; and he did not. The cockpit lighting was dim inside; so I had good visibility outside. The night sky was bright with an almost full moon behind us. Some stars and planets were out; but the milky way was barely visible due to the moon. A light; ahead and slightly to the right initially caught my eye. It went from dim to extremely bright in just a few seconds. It was above the horizon about 20 degrees inclination and around my 12:30 O'clock position. It was not in close to us; but seemed out there a bit. I have never seen such intense; bright; white and silver light in my life. It actually had a very defined 360 degree halo around it at one point. Then it made a 45 degree sharp change in direction and faded away as it went out of view in about 3 seconds time. During the next 50 mins; we experienced almost the exact same scenario 4 more times. The first officer witnessed all 4 of those events. We made 'cirvis' type reports to ATC for each encounter thereafter. The last one we saw was on descent into ZZZ around 17000 ft as we entered a cloud. Supplemental information from acn 795850: I did not see it until 5-10 mins later when it occurred again. Object started out as a very weak-looking STAR; but would move slowly left to right and grow much brighter than any STAR I have ever seen. It would then begin to fade and move further right; appearing to move off to the distant northwest. The captain and I observed the same phenomenon 3 more times; each occurrence 5-10 mins after the last. The lowest altitude at which it was visible was approximately FL190. I have background in the USAF; and the closest I could describe this point of light would possibly be similar to an airborne-launched missile.

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Original NASA ASRS Text

Title: AN ACR CREW AT FL360 NEAR TNP REPORTS AN UNUSUAL BRIGHT OBJECT TRAVELING FROM THE SOUTHWEST BECOMING INTENSELY BRIGHT AND THEN FADING INTO NORTHWEST.

Narrative: WHILE FLYING WE ENCOUNTERED MULTIPLE UNUSUAL SIGHTINGS AT ALT. AROUND XA30Z AT FL360; 20 MI N OF TNP; I WITNESSED THE FIRST SUCH EVENT. I QUERIED ATC ABOUT WHAT I HAD SEEN; BUT WAS NOT TOO CONCERNED AT THIS POINT. IT WAS UNUSUAL AND UNLIKE ANYTHING I HAD SEEN BEFORE; BUT LASTED ONLY AROUND 10 SECONDS. I ASKED THE FO IF HE HAD SEEN WHAT I SAW; AND HE DID NOT. THE COCKPIT LIGHTING WAS DIM INSIDE; SO I HAD GOOD VISIBILITY OUTSIDE. THE NIGHT SKY WAS BRIGHT WITH AN ALMOST FULL MOON BEHIND US. SOME STARS AND PLANETS WERE OUT; BUT THE MILKY WAY WAS BARELY VISIBLE DUE TO THE MOON. A LIGHT; AHEAD AND SLIGHTLY TO THE R INITIALLY CAUGHT MY EYE. IT WENT FROM DIM TO EXTREMELY BRIGHT IN JUST A FEW SECONDS. IT WAS ABOVE THE HORIZON ABOUT 20 DEGS INCLINATION AND AROUND MY 12:30 O'CLOCK POS. IT WAS NOT IN CLOSE TO US; BUT SEEMED OUT THERE A BIT. I HAVE NEVER SEEN SUCH INTENSE; BRIGHT; WHITE AND SILVER LIGHT IN MY LIFE. IT ACTUALLY HAD A VERY DEFINED 360 DEG HALO AROUND IT AT ONE POINT. THEN IT MADE A 45 DEG SHARP CHANGE IN DIRECTION AND FADED AWAY AS IT WENT OUT OF VIEW IN ABOUT 3 SECONDS TIME. DURING THE NEXT 50 MINS; WE EXPERIENCED ALMOST THE EXACT SAME SCENARIO 4 MORE TIMES. THE FO WITNESSED ALL 4 OF THOSE EVENTS. WE MADE 'CIRVIS' TYPE RPTS TO ATC FOR EACH ENCOUNTER THEREAFTER. THE LAST ONE WE SAW WAS ON DSCNT INTO ZZZ AROUND 17000 FT AS WE ENTERED A CLOUD. SUPPLEMENTAL INFO FROM ACN 795850: I DID NOT SEE IT UNTIL 5-10 MINS LATER WHEN IT OCCURRED AGAIN. OBJECT STARTED OUT AS A VERY WEAK-LOOKING STAR; BUT WOULD MOVE SLOWLY L TO R AND GROW MUCH BRIGHTER THAN ANY STAR I HAVE EVER SEEN. IT WOULD THEN BEGIN TO FADE AND MOVE FURTHER R; APPEARING TO MOVE OFF TO THE DISTANT NW. THE CAPT AND I OBSERVED THE SAME PHENOMENON 3 MORE TIMES; EACH OCCURRENCE 5-10 MINS AFTER THE LAST. THE LOWEST ALT AT WHICH IT WAS VISIBLE WAS APPROX FL190. I HAVE BACKGROUND IN THE USAF; AND THE CLOSEST I COULD DESCRIBE THIS POINT OF LIGHT WOULD POSSIBLY BE SIMILAR TO AN AIRBORNE-LAUNCHED MISSILE.

Data retrieved from NASA's ASRS site as of May 2009 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.