Sky conditions were very clear with high visibility from moonlight. a friend and i were fishing along the susquehanna river. i looked up several times to observe stars and the usual satellites and aircraft fly overhead. one particular object at first resembled a satellite because of it's light, speed, and high altitude caught my attention. i was following it's travel path when it began to act erratically. it began to zigzag and appeared to be descending altitude. the speed it was moving was about 10 times faster compared to the normal aircraft seen throughout the night. this descending last for about 2-3 min. the light was a white/yellow very bright. no blinking lights like a normal aircraft. light was aura like as it appeared to hide conceal the shape of the object. the object slowed down to a slow hover at about 1000 ft or less and about 0.5-1 mile northeast of my location. there was no noise the entire time even when it was very close. the light all of sudden went out leaving the silhouette of the object visible against the moonlight for about a second or two. next, the object appeared to flip over and illuminated a small flash before slowly disappearing. this is the best i can describe this because the light going out and the object disappearing happened within a few seconds. it didn't fly away or look as if it went into a hyper speed. it was as if the object went invisible. about 3 weeks later in the daytime i was driving in the same approximate area and as i came over a hill i same type of light hovering over the same mountain range. i had to pull over. the object was only about 500 ft or less over the mountain. it lasted for about 10 seconds before the light abruptly went out just like the first time. after the light went out the object itself was visible for about 2-3 seconds before slowly fading out or disappearing. i can only describe the shape as a disc in a diagnol position about the size of a ac-130. i am a scientific person with an open mind and this experience blew my mind and is very hard to explain. this craft was nothing like anything i have ever seen. i have seen all types of aircraft, seen shooting stars, drones, space debris re-enter but this was absolutely like none of this.