I was with my girlfriend waiting for the bus to go back to my house, when I noticed what I believed that was a star moving very slowly.
I told my girlfriend and she confirmed that I was not just seeing things, and even pointed out another light coming from the same southwest to west direction.
Both of them were glowing, but one had an ever-changing color that varied from orange to yellow and the other blue to white.
At first, I though they where sattelites, but as soon as I told that to my girlfriend the objects had changed their direction.
We spent about 15 minutes watching the event, when the UFO extinguished its lights immediately after reaching (far on the sky) a position over us.
I was amazed by the scene, as it's not the first time I've seen an UFO, but this time it was different.
This time it was a good experience because of its duration and the fact that when we arrived there on that afternoon I felt that I was going to see something and I must have kept an eye on the sky.
Source and special thanks: UFO Casebook