Oh what was that?

[Anirbas]

Ok so my friend called me and I went out on our deck because it was a nice night. While I was talking to him this object I took to be an airplane came from my left and slowly traveled overhead. I noticed it was kind of low but didn't really pay attention to it because at this point I still thought it was an airplane. The reason I took it to be an airplane is because tehre was another traveling much higher at the time making the usual airplane noise (our house is in a direct path of the airport). Soon the plane making the noise was gone and it was silent. The object continued traveling rather slowly and it went far to my right maybe 1/2 an acre away or so and it just slowly dimmed from the outside in and was black then all of a sudden it lit back up as bright as ever. It then continued back to the left but behind me. I eventually got tired of watching it. It seemed to be headed over a mountian. What do you all think it was? I have my doubts about my airplane theory now!